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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.
111

Unraveling the Impact of Corruption on the Effectiveness and Integrity of Humanitarian Action during the Ebola Response in the Eastern DRC from 2018 to 2020.

Kunda, Claudine January 2024 (has links)
This thesis examines the pervasive impact of corruption on the effectiveness and integrity of humanitarian action, focusing on the Ebola response in the Democratic Republic of Congo from 2018 to 2020. Triggered by a 2020 operational review by the United Nations’ anti-fraud taskforce, agencies and aid groups in the Democratic Republic of Congo that uncovered a large-scale fraud scheme in the Ebola response, this study reveals severe corruption affecting various facets of the humanitarian intervention, including staff recruitment, supply procurement, and aid delivery. The findings highlight how aid intended for vulnerable populations was diverted through fraudulent schemes, bribery, kickbacks, and widespread exploitation involving multiple stakeholders, ultimately undermining the trust and efficacy of the response. Drawing on principal-agent theory, this research delves into how moral hazard, information asymmetry, and inadequate monitoring facilitated corrupt practices within the complex and conflict-ridden context of the DRC. It underscores the need for enhanced transparency and accountability mechanisms to prevent corruption and ensure aid reaches those most in need. The thesis employs qualitative methods, including in-depth document analysis of academic articles, government reports, NGO publications, and news sources. By addressing the intersection of corruption and humanitarian action, this study contributes to the scientific understanding of corruption's detrimental effects on humanitarian efforts. It proposes strategies to improve transparency and accountability in humanitarian interventions, aiming to safeguard the integrity and effectiveness of aid in challenging environments like the DRC.
112

Protection of the right of healthcare of people infected with ebola virus disease (EVD) : a human rights-based approach

Nwafor, Gloria Chidimma January 2016 (has links)
LLM / Department of Public Law / Human rights are those inalienable rights of an individual by virtue of being a human being. They are guaranteed by various domestic and international instruments. This research argues that despite the existence of these instruments and wide acceptances of international human rights standards that seek to protect the right to healthcare, the people infected with Ebola Virus Disease (EVD) are victims of a wide range of constraints to their right to healthcare as a result of the failure by the governments of the respective nations where the impacts of the EVD are mostly felt to discharge their obligations under those instruments. The rights of the people infected with EVD are often violated because of their presumed or known EVD status, causing them to suffer both the burden of the disease and the social burden of discrimination and stigmatisation which could deter the infected persons from accessing available treatment. This would invariably contribute to the spread of the disease. The research further exposes the dilemma posed by the EVD to the healthcare system, where healthcare providers are caught between the rock of selfpreservation from a highly virulent disease and the hard place of discharging their Hippocratic Oath which prescribes ethical guidelines for the discharge of the duties of the medical profession. The present research, which is novel in the field of medico-legal research, seeks to proffer answers to this conundrum.
113

Cellules NK et fièvres hémorragiques virales : étude de leur rôle dans la mise en place des réponses immunes et dans la pathogenèse lors de l'infection par les virus Lassa et Ebola / Natural Killer cells and hemorrhagic fevers : study of their role in the induction of the immune responses and the pathogenesis during the infection by Lassa and Ebola viruses

Russier, Marion 06 February 2013 (has links)
Les fièvres hémorragiques à virus Lassa (LASV) et Ebola (EBOV) représentent un important problème de santé publique en Afrique. Les réponses immunes et la pathogenèse associées à ces maladies sont peu connues. Les cellules NK ont un rôle important dans la réponse immune innée par leurs propriétés cytotoxiques, mais également dans l’induction des réponses adaptatives par leur production de cytokines et leurs interactions avec les cellules dendritiques (DC) et les macrophages. Ce projet s’attache à comprendre le rôle des cellules NK dans le contrôle de la réplication virale et dans l’induction des réponses immunitaires au cours de ces infections. Un modèle in vitro de coculture de cellules NK humaines avec des DC et macrophages autologues a été développé. L’activation des cellules NK et leurs fonctions ont été analysées après l’infection par LASV et EBOV. Par ailleurs, les réponses des cellules NK en réponse à LASV ont été comparées avec celles induites lors de l’infection par le virus Mopeia (MOPV), très proche de LASV mais non pathogène pour l’homme. Les macrophages, mais pas les DC, infectés par LASV ou MOPV induisent l’activation et l’augmentation des capacités cytotoxiques des cellules NK. Toutefois, les cellules NK ne sont pas capables de lyser les cellules infectées et ne produisent pas d’IFN-γ. Les cellules NK s’activent et sont capables de lyser les cellules infectées en présence de macrophages mais également de DC infectés par des LASV mutants. Cependant, les IFN de type I sécrétés en grande quantité en réponse à ces virus ne sont pas impliqués dans l’activation des cellules NK. L’infection par EBOV n’induit qu’une très faible activation des cellules NK en présence de DC ou macrophages et ne conduit pas à la sécrétion de cytokines, ni à la modification du potentiel cytotoxique.Ces résultats permettent d’améliorer la compréhension des réponses immunes et des mécanismes de pathogenèse mis en place lors des fièvres hémorragiques Lassa et Ebola. / The hemorrhagic fevers caused by Lassa (LASV) and Ebola (EBOV) viruses are important problems of public health in Africa. The immune responses and the pathogenesis associated with these diseases are unknown. NK cells are at the crossroads between the innate and adaptive immune responses through their abilities to secrete cytokines and kill the infected cells. The interactions between NK cells and dendritic cells (DC) or macrophages potentiate the immune responses. This project aims to understand the role of NK cells in the control of viral replication and in the induction of immune responses during LASV and EBOV infection.An in vitro model of coculture of human NK cells with autologous DC or macrophages has been set up. Cell activation, cytokine production, proliferation and NK cell-mediated killing were analyzed after the infection with LASV or EBOV. In addition, NK cell functions in response to LASV were compared with those induced during Mopeia virus (MOPV) infection, closely related to LASV but not pathogenic for humans.Here, we show that LASV- or MOPV-infected macrophages, but not DC, induce the activation of NK cells and the increase of their cytotoxic capacity. This process involves cell contact and type I IFN. However, these cells are neither able to kill the infected cells nor produce IFN-γ. NK cells are activated and are able to kill the infected cells when stimulated by mutated LASV-infected macrophages and DC. Surprisingly, the type I IFN which are secreted in high amounts in response to these viruses are not involved in NK cell activation. EBOV infection does not lead to NK cell activation in the presence of DC. EBOV-infected macrophages induce low NK cell activation without cytokine production or cytotoxicity.These results allow to better understand the immune responses and the mechanisms of pathogenesis associated with Lassa and Ebola hemorrhagic fevers.
114

Structural studies on a hepatitis C virus-related immunological complex and on Ebola virus polymerase cofactor VP35

Fadda, Valeria January 2015 (has links)
Hepatitis C virus (HCV) is one of the leading causes of hepatocellular carcinoma worldwide. HCV-neutralizing antibody AP33 recognizes a linear, highly conserved epitope on the viral entry protein E2, disrupting the interaction with the cellular receptor CD81 that leads to viral entry. AP33-related anti-idiotypes (Ab₂s) have the potential to carry the internal image of the antigen E2, eliciting the production of AP33-like antibodies in humans. This study reports the mid-resolution structure of the Fab fragment of anti-idiotype A164.3 and the high-resolution structure of the Fab fragment of AP33 in complex with the Fv fragment of anti-idiotype B2.1A. Analysis of the structures and comparison with the previously published structure of AP33 in complex with a peptide corresponding to the E2 epitope, suggests that while A164.3 does not mimic the antigen E2, B2.1A is characterized by high surface complementarity with AP33 and functional antigen mimicry. Thus, B2.1A can be classified as an Ab₂-β, a subgroup of anti-idiotypes carrying the internal image of the antigen. Preliminary binding studies show that AP33 binds B2.1A with nanomolar affinity, supporting the role of B2.1A as an idiotypic vaccine candidate. Zaire ebola virus causes severe, often lethal hemorrhagic fever in humans. Ebola virus polymerase cofactor VP35 is a multifunctional protein involved in, among other functions, dsRNA binding and inhibition of the host's interferon pathways. VP35 contains an N-terminal oligomerization domain and a C-terminal dsRNA-binding domain (RBD). Preliminary results on the oligomerization domain of VP35 suggest that this region contains a coiled-coil motif, as previously reported. In order to validate a recently-discovered dsRNA end-capping pocket as a drug target, the structure of VP35 RBD I278A mutant was solved at high resolution, showing that even a small perturbation in the binding pocket can cause dramatic binding impairment due to loss of contacts with dsRNA.
115

Applied mathematical modelling with new parameters and applications to some real life problems

Mugisha, Stella 09 1900 (has links)
Some Epidemic models with fractional derivatives were proved to be well-defined, well-posed and more accurate [34, 51, 116], compared to models with the conventional derivative. An Ebola epidemic model with non-linear transmission is fully analyzed. The model is expressed with the conventional time derivative with a new parameter included, which happens to be fractional (that derivative is called the 􀀀derivative). We proved that the model is well-de ned and well-posed. Moreover, conditions for boundedness and dissipativity of the trajectories are established. Exploiting the generalized Routh-Hurwitz Criteria, existence and stability analysis of equilibrium points for the Ebola model are performed to show that they are strongly dependent on the non-linear transmission. In particular, conditions for existence and stability of a unique endemic equilibrium to the Ebola system are given. Numerical simulations are provided for particular expressions of the non-linear transmission, with model's parameters taking di erent values. The resulting simulations are in concordance with the usual threshold behavior. The results obtained here may be signi cant for the ght and prevention against Ebola haemorrhagic fever that has so far exterminated hundreds of families and is still a ecting many people in West-Africa and other parts of the world. The full comprehension and handling of the phenomenon of shattering, sometime happening during the process of polymer chain degradation [129, 142], remains unsolved when using the traditional evolution equations describing the degradation. This traditional model has been proved to be very hard to handle as it involves evolution of two intertwined quantities. Moreover, the explicit form of its solution is, in general, impossible to obtain. We explore the possibility of generalizing evolution equation modeling the polymer chain degradation and analyze the model with the conventional time derivative with a new parameter. We consider the general case where the breakup rate depends on the size of the chain breaking up. In the process, the alternative version of Sumudu integral transform is used to provide an explicit form of the general solution representing the evolution of polymer sizes distribution. In particular, we show that this evolution exhibits existence of complex periodic properties due to the presence of cosine and sine functions governing the solutions. Numerical simulations are performed for some particular cases and prove that the system describing the polymer chain degradation contains complex and simple harmonic poles whose e ects are given by these functions or a combination of them. This result may be crucial in the ongoing research to better handle and explain the phenomenon of shattering. Lastly, it has become a conjecture that power series like Mittag-Le er functions and their variants naturally govern solutions to most of generalized fractional evolution models such as kinetic, di usion or relaxation equations. The question is to say whether or not this is always true! Whence, three generalized evolution equations with an additional fractional parameter are solved analytically with conventional techniques. These are processes related to stationary state system, relaxation and di usion. In the analysis, we exploit the Sumudu transform to show that investigation on the stationary state system leads to results of invariability. However, unlike other models, the generalized di usion and relaxation models are proven not to be governed by Mittag-Le er functions or any of their variants, but rather by a parameterized exponential function, new in the literature, more accurate and easier to handle. Graphical representations are performed and also show how that parameter, called ; can be used to control the stationarity of such generalized models. / Mathematical Sciences / Ph. D. (Applied Mathematics)
116

Synthesis of small molecules targeting filovirus inhibition / Synthèse de petites molécules ciblant l'inhibition filovirus

Niemiec-Plebanek, Elzbieta 19 December 2014 (has links)
Les virus sont au centre de problème de santé publique. En raison de l'apparition de nouveaux virus et pour certains de leur résistance aux traitements existants il est toujours d’actualité de développement de nouveaux agents antiviraux. En général, la stratégie de lutte contre les infections virales est basée sur la vaccination ou sur l'activité des petites molécules, interférant avec un ou plusieurs processus biologiques participant au cycle de vie du virus. Dans ce contexte, nous avons conçu et synthétisé des petites bibliothèques de molécules visant des propriétés anti-filovirus. Dans ce projet de recherche, nous avons mis l'accent sur le développement de composés ciblant la protéine Niemann-Pick C1, les protéases cathepsine et le processus de réplication. Lors du développement des inhibiteurs de Neimann-Pick C1 plus de 70 composés ont été synthétisés, portant le squelette pipérazine. Afin d'obtenir des inhibiteurs de cystéine cathepsines pouvant être impliqués dans la réplication du virus Ebola, nous avons synthétisé une petite bibliothèque de composés porteurs de groupement 1,3,5-triazine et possédant des activité de l’ordre du nanomolaire sur les cathepsines B, K, L et S. Enfin, pour inhiber la réplication du virus en ciblant SAH hydrolase, nous avons proposé une série de C-nucléosides carbocyclic ayant motif de 4-aza-7,9-dideazaadenosine. / The viruses cause the problem of public health. Due to the appearance of new viruses and their resistance to existing treatments there is still relevant to develop new antivirals. Generally, the strategy to combat viral infections is based on vaccination or on the activity of small molecules, interfering with one or more biological processes participating in virus life cycle. In this context, we took an effort to design and synthesize the library of small molecules possessing anti-filovirus properties. In this research project, we were focused on the developing of compounds targeting Niemann-Pick C1 protein, cathepsin proteases and replication process. In our effort into the development of the inhibitors of Neimann-Pick C1 we prepared the series of about 70 compounds, having in common the piperazine moiety. Diverse 1,4-N,N - substituents of piperazine, differencing in a size and shape were studied. In order to obtain efficient cysteine cathepsins inhibitors, we synthesized the small library of compounds bearing 1,3,5-triazine moiety. Finally, to inhibit the virus replication by targeting SAH hydrolase, we proposed the series of carbocyclic C-nucleosides having motif of 4-aza-7,9-dideazaadenosine.
117

Electrochemically Exfoliated High-Quality 2H-MoS₂ for Multiflake Thin Film Flexible Biosensors

Zhang, Panpan, Yang, Sheng, Pineda-Gómez, Roberto, Ibarlucea, Bergoi, Ma, Ji, Lohe, Martin R., Akbar, Teuku Fawzul, Baraban, Larysa, Cuniberti, Gianaurelio, Feng, Xinliang 17 December 2020 (has links)
2D molybdenum disulfide (MoS₂) gives a new inspiration for the field of nanoelectronics, photovoltaics, and sensorics. However, the most common processing technology, e.g., liquid‐phase based scalable exfoliation used for device fabrication, leads to the number of shortcomings that impede their large area production and integration. Major challenges are associated with the small size and low concentration of MoS₂ flakes, as well as insufficient control over their physical properties, e.g., internal heterogeneity of the metallic and semiconducting phases. Here it is demonstrated that large semiconducting MoS₂ sheets (with dimensions up to 50 µm) can be obtained by a facile cathodic exfoliation approach in nonaqueous electrolyte. The synthetic process avoids surface oxidation thus preserving the MoS₂ sheets with intact crystalline structure. It is further demonstrated at the proof‐of‐concept level, a solution‐processed large area (60 × 60 µm) flexible Ebola biosensor, based on a MoS₂ thin film (6 µm thickness) fabricated via restacking of the multiple flakes on the polyimide substrate. The experimental results reveal a low detection limit (in femtomolar–picomolar range) of the fabricated sensor devices. The presented exfoliation method opens up new opportunities for fabrication of large arrays of multifunctional biomedical devices based on novel 2D materials.
118

Mycket (risk)retorik : En kvantitativ retorikanalys av Folkhälsomyndighetens kommunikation om Covid-19 och Ebola. / Much (risk)rhetorics : A quantitative rhetorical analysis of Folkhälsomyndigheten's communication regarding Covid-19 and Ebola.

Jacobs, Fabian, Levinson, Alexander January 2020 (has links)
Hur myndigheter kommunicerar under kristider spelar en avgörande roll för hur både samhälle och näringsliv hanterar en kris. Denna deskriptiva studie undersöker hur Folkhälsomyndigheten kommunicerat under två pandemier, Covid-19 och Ebola, för att beskriva hur en svensk myndighet kommunikativt hanterat allvarliga kriser. Studien har tillämpat en kvantitativ innehållsanalys för att granska en större mängd publikationer och mäta teoretiskt intressanta egenskaper i Folkhälsomyndighetens kommunikation. För att fylla vad vi menar är en forskningslucka, den kvantitativa retorikanalysen, har operationaliseringar av centrala retoriska begrepp gjorts. Två urval har gjorts från Folkhälsomyndighetens nyhetsarkiv; ett totalurval av Ebola-publikationer (N=12) och ett slumpmässigt urval av Covid-19-publikationer (n=83), vilket sammantaget resulterade i 95 analysenheter. Dataanalys av publikationerna genomfördes i dataanalysprogrammet SPSS. Vår studie fann att Folkhälsomyndighetens riskkommunikation var dynamisk och anpassades utefter hur allvarlig en kris var och hur den utvecklades. Exempelvis manifesterade myndigheten risker när utvecklingen av Covid-19 var oroväckande och tvärtom, när pandemin var mindre allvarlig under sommarmånaderna. Myndigheten axlar huvudsakligen en rådgivande roll i kristider, i närmare 9 av 10 fall framkommer en eller flera uppmaningar om hur samhället bör förhålla sig till Covid-19. Vidare visar analysen att myndigheten vilade sin argumentation på sakliga eller statistiska bevis (ex. dokument eller forskningsrapporter) i mer än 70 procent av fallen, vilket tyder på ett rationellt övertygande. Studien visar prov på hur en kvantitativ retorikanalys kan genomföras och fyller därmed en forskningslucka. Vidare diskuteras vilka för- och nackdelar som uppstår när teoretiska begrepp omvandlas (operationaliseras) till mätbara variabler. / How authorities communicate during times of crisis plays a crucial part in how society and commerce manages a crisis. This descriptive analysis examines how the Swedish public health authority Folkhälsomyndigheten has communicated during two pandemics, Covid-19 and Ebola, in goal of depicturing how a Swedish government agency has communicated whilst handling a serious risk to public health. The study has applied a quantitative content analysis to examine a large number of publications and measure theoretically interesting properties in Folkhälsomyndigheten’s communication. Central rhetorical concepts have been operationalized and measured in order to fill what we perceive to be a research method gap, the quantitative rhetorical analysis. Two samples have been drawn from Folkhälsomyndigheten’s news archive; a complete sample of Ebola publications (N=12), and a sample of Covid-19 publications (n=83), resulting in a total of 95 units. The data analysis of the publications was performed using the data analysis program SPSS. Our study found that Folkhälsomyndigheten’s risk communication was dynamic and adapted to how severe a crisis was and how it developed. For example, the agency manifested the risks when Covid-19’s development was alarming, and the other way around when the development was less alarming during summer months. The agency primarily holds an advisory role in times of crisis; in almost 9 out of 10 cases one or more appeals or guidelines to the general public is apparent, on how society should adapt to Covid-19. Furthermore, our analysis shows that the agency bases their arguments on facts and statistics evidence (e.g. documentation or research reports) in more than 70 percent of the cases. Which suggests a rational persuasion tactic. The study exemplifies how a quantitative rhetorical analysis can be executed, and thus fills a research gap. In addition, the study discusses the pros and cons of converting (operationalizing) theoretical concepts to measurable variables.
119

Sekuritizace biologie: Biologické hrozby a připravenost státu v kontextu pandemie / Securitising biology: Biological threats and state preparedness in the wake of a pandemic

Artico, Chiara January 2021 (has links)
64053643 SECURITISING BIOLOGY: BIOLOGICAL THREATS AND STATE PREPAREDNESS IN THE WAKE OF A PANDEMIC ABSTRACT The management of infectious diseases in the realm of public health has shown increasingly overlapping areas with biological warfare preparedness. While the acknowledgement of these common elements is not only frequent but also codified in an international treaty and subject to distinct regulations, research into how these two fields connect is scarce. Potential deliberate use of biological weapons typically leads to intense political mobilisation and ensuing dedication of financial resources. Contrarily, the management of health crises over the last decades has been severely flawed, and no country in the world is considered fully prepared to a pandemic, according to the Global Health Security Index. The current COVID-19 pandemic has recently been further proof of the inadequacy of state-level prevention and preparedness capabilities. This dissertation aims at bridging the existing conceptual gap and policy divide between biological warfare and infectious disease preparedness, and to analyse elements that can be mutually applicable and potentially beneficial. It will do so by establishing analytical equivalence between the securitisation of an artificial biothreat and a nature-borne infectious disease...
120

Determining the Reservoir Species of Zaire Ebola Virus: A Proposed Epidemiological Survey

Hohnstein, Nicole M 01 January 2016 (has links)
Ebola virus (EBOV) is a re-emerging zoonotic virus (it is transmitted between animals and humans) that causes acute hemorrhagic fever and a high fatality rate in humans. First reported in 1976 in the Democratic Republic of the Congo (formerly Zaire), the virus is transmitted between humans through direct contact with body fluids of an infected person, causing fever, weakness, diarrhea, abdominal pain, cramping, nausea and vomiting in those affected. There is neither a licensed vaccine nor an approved treatment for Ebola virus in human patients. The reservoir species for Ebola virus is similarly unknown, as many studies have attempted yet failed to isolate living virus from potential candidates. The widely accepted and circulated hypothesis based on preliminary findings of outbreaks past is that bat species, specifically the fruit bat species Hypsignathus monstrosus, Epomops franqueti and Myonycteris torquata are potential reservoirs. Recent reports, especially concerning findings from the 2014 Ebola outbreak, have determined that insectivorous bats could similarly be reservoir species. Successful isolation of a live virus from a bat species found through a widened sampling of a variety of bat species would confirm the hypothesis that bats, either fruit or insectivorous, are the reservoir species for Ebola virus.

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