41 research outputs found
PriorViabilitySelectionSoaySheep
No full textThe code in this repository is to run the models presented in the manuscript above. In this study we assess quantitative genetic parameters to gain an evolutionary explanation as to why adult size traits are not evolving in the direction of current estimates of the response to selection within this wild population of Soay sheep. Elizabeth A. Mittell1,2,*, Josephine M. Pemberton1, Loeske E. B. Kruuk1 & Michael B. Morrissey2 1 - Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, UK; 2 - School of Biology, University of St. Andrews, UK *Corresponding author: Elizabeth A. Mittell, [email protected], [email protected]; Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, EH9 2LD, UK J.M.P, M.B.M, L.E.B.K, and E.A.M collected the data. E.A.M and M.B.M analysed the data. E.A.M is responsible for the code in this repository
A Qualitative Study of Perceived Risk for HIV Transmission among Police Officers in Dar es Salaam, Tanzania.
No full textUnderstanding people's views about HIV transmission by investigating a specific population may help to design effective HIV prevention strategies. In addition, knowing the inherent sexual practices of such a population, as well as the risky circumstances that may facilitate HIV transmission, is crucial for the said strategies to become effective. In this article, we report how police officers in Dar es Salaam, Tanzania, perceived the problem of HIV and AIDS in their local context, particularly in relation to unsafe sexual practices. The study was done with the view to recommending ways by which HIV transmission could be minimised within the police force. The study was conducted among members of the police force in Dar es Salaam, Tanzania. Eight focus group discussions (FGDs) were conducted, with a total of 66 participants who were mixed in terms of age, gender, and marital status. Some of these were caregivers to patients with AIDS. Data were analysed using the interpretive description approach. The participants believed that both individual sexual behaviour and work-related circumstances were sources of HIV infection. They also admitted that they were being tempted to engage in risky sexual practices because of the institutional rules that prohibit officers from getting married during their training and for three years after. Nevertheless, as members of the Police Force, they stressed the fact that the risky sexual behaviour that exposes them to HIV is not limited to the force; it is rather a common problem that is faced by the general population. However, they complained, the nature of their job exposes them to road accident victims, subjecting them further to possible infection, especially when they have to handle these road accident casualties without proper protective gear. Individual sexual behaviour and job-related circumstances are worth investigating if proper advice is to be given to the police regarding HIV prevention strategies. In order to improve the lives of these police officers, there is a need to review the existing institutional rules and practices to accommodate individual sexual needs. In addition, improving their working environment may minimize the risk of HIV transmission from handling casualties in emergency situations
Help Me Help You. Designing Support for Person-Product Collaboration
No full textThis thesis explores how to make appliances, such as thermostats, televisions and microwave ovens, easier to program. It does so by looking at person-product interaction as a type of collaborative planning dialogues. The user and product must âtalkâ to each other, engaging in a collaborative dialogue that can lead to a shared plan concerning their mutually held beliefs and goals. The design challenge discussed in this thesis centers on the creation of product interfaces that facilitate collaborative person-product planning. In particular, a product interface should capitalize on the complementary strengths of the person and product: the product's ability to interpret user actions and goals and make efficient plans to achieve them, and the person's knowledge of what he or she wants to do. This goal is captured in the Help Me Help You (HMHY) principle, namely that a programmable product interface needs to be designed to help the user to better help the product know what the user wants to do, and thus better able to help the user. In other words, programmable appliance interfaces need to be designed to support person-product collaboration. The research question addressed in this thesis is how to develop a practical design method for supporting person-product collaboration from existing models of collaboration discourse. The design research in this thesis focused on the 'Some Things To Say (SenSay)' a modular adaptive menu derived from task models using collaborative discourse theory. The questions of how to design the SenSay from the theory and how people actually use it to get things done, as well as new methods for exploring and evaluating SenSay design, are all addressed across the different chapters of this thesis.Design, Engineering and Productio
Geomechanical modelling and subsidence prediction of salt deposits for solution mining
No full textSection Resources EngineeringGeoscience & EngineeringCivil Engineering and Geoscience
Sedimentation of Oil Sands Tailings
No full textIn Alberta (Canada) bitumen is extracted from the mined oil sands ore by a process that uses hot water. This process produces large amounts of tailings, which is a mixture of water and sediment particles. These tailings are stored in large ponds to allow the sediments to settle out of suspension. The water is recycled in the hot-water process and the solids are used for land reclamation in the mine site areas that have been mined out. The fine particles in the tailings settle very slowly so companies are trying to find ways to accelerate the dewatering process. A dewatering process consists of three phases: sedimentation, consolidation and ripening when the sediment layer is exposed to air. Samples of the tailings were shipped to Delft University of Technology to perform dewatering experiments. From one of the first experiments it was suspected that the moisture content of the samples was already too low for the sedimentation phase to precede the consolidation phase. The goal of this project was to find out if there is a relation between the moisture content at the transition between the sedimentation and consolidation phases and the liquid limit and liquidity index of the soil. To be able to compare the results with another type of soil, the same tests were performed on river clay. Three sedimentation columns with different moisture contents were prepared for each of the materials and standard tests (BS 1377) were performed on the soils to determine the liquid and plastic limit from which the liquidity index was derived. To further characterize the materials, hydrometer tests were performed. From the British soil classification chart was deduced that the thickened tailings were to be classified as an intermediate plasticity clay and the river clay as a high plasticity clay. The major conclusion that may be drawn from the test results is that the liquidity index at the boundary between sedimentation and consolidation for both materials is around 18 and 19 for both soils. Furthermore the moisture content at the transition from the sedimentation phase to the consolidation phase is around ten times higher than the liquid limits of the materials. Another conclusion is that the consolidation phase shows no acceleration on a logarithmic time scale when it is preceded by the sedimentation phase, where this acceleration is visible when the sedimentation phase does not occur.Geo-engineering SectionGeotechnologyCivil Engineering and Geoscience
Sport in Public Space: A reclaimed position for sport- and activity structures in the immediate living environment: A design study for Alkmaar West
No full textNowadays various Dutch cities have a very programmatic arrangement in which sport and activity structures often are situated at the borders of the city, along highways and railroads, as mono-functional complexes and stand-alone islands enclosed by greenery. The graduation project 'Sport in Public Space' is a design research that looks for ways in which sport- and activity structures can be repositioned and integrated into the direct living and working areas of the city, using Alkmaar West as a test case.Research group Design of the Urban FabricUrbanismArchitecture and The Built Environmen
Willingness to volunteer in a Phase I/II HIV vaccine trial: a study among police officers in Dar es Salaam, Tanzania
No full textBackground: As HIV infection continues to devastate low-income countries, efforts to search for an effective
HIV vaccine are crucial. Therefore, participation in HIV vaccine trials will be useful for the development of a
preventive vaccine that will work and thus reduce the global HIV epidemic.
Objective: The objective of this study was to analyse the willingness to volunteer (WTV) in a Phase I/II HIV
vaccine trial among police officers in Dar es Salaam, Tanzania.
Design: We included a convenience sample of 329 participants (79% males) from sensitisation workshops that
were held once at each of the 32 police stations. Participants were recruited from 23 stations which were
included according to availability. Data about personal characteristics, general HIV and AIDS knowledge and
sexual behaviour, attitudes towards vaccines and willingness to participate in the HIV vaccine trial were
obtained through an interview-administered questionnaire with both closed and open-ended questions.
Results: Overall, 61% of the participants expressed WTV in HIV vaccine trials. WTV was significantly
associated with: positive attitude towards use of effective vaccine, Odds ratio (OR), 36.48 (95% CI: 15.07
88.28); the intention to tell others about one’s decision to participate in the trial, OR, 6.61 (95% CI: 3.89
11.24); Tanzania becoming a partner in developing the vaccine, OR, 4.28 (95% CI: 2.28 8.03); having an extra
sexual partner, OR, 3.05 (95% CI: 1.63 5.69); perceived higher risk of getting HIV infection, OR, 2.11 (95%
CI: 1.34 3.33); and high knowledge about HIV and AIDS, OR, 1.92 (95% CI: 1.22 3.01).
Conclusion: The results indicated that a majority of police officers in this study were willing to participate in
HIV vaccine trials. However, there is a need to provide the respondents with precise information about the
purpose of a Phase I/II HIV vaccine trial and the fact that it does not protect against HIV infection, in order
to avoid increasing risky behaviour
Balancing Collective Responsibility, Individual Opportunities and Risks: A Qualitative Study on How Police Officers Reason Around Volunteering in an HIV Vaccine Trial in Dar es Salaam, Tanzania.
No full textResults from HIV vaccine trials on potential volunteers will contribute to global efforts to develop an HIV vaccine. The purpose of this study among police officers in Dar es Salaam, Tanzania, was to explore the underlying reasons that induce people to enrol in an HIV vaccine trial.\ud
We conducted discussions with eight focus groups, containing a total of 66 police officers. The information collected was analyzed using interpretive description. The results showed that participants were motivated to participate in the trial by altruism, and that the participants experienced some concerns about their participation. They stated that altruism in the fight against HIV infection was the main reason for enrolling in the trial. However, young participants were seriously concerned about a possible loss of close relationships if they enrolled in the HIV vaccine trial. Both men and women feared the effect of the trial on their reproductive biology, and they feared interference with pregnancy norms. They were unsure about risks such as the risks of acquiring HIV infection and of suffering physical harm, and they were unsure of the intentions of the researchers conducting the trial. Further, enrolling in the trial required medical examination, and this led some participants to fear that unknown diseases would be revealed. Other participants, however, saw an opportunity to obtain free health services.\ud
We have shown that specific fears are important concerns when recruiting volunteers to an HIV vaccine trial. More knowledge is needed to determine participants' views and to ensure that they understand the conduct of the trial and the reasons it is being carried out
Exploring the effects of post-tensioning an all glass column of the bundled type to enhance slenderness and promote safe failure behavior
No full textThe long and slender structural member, the elastic column, fails due to buckling. Buckling is a predictable, and visible, mode of failure allowing for timely repairs or replacement. This is no longer true when we look at long and slender columns made out of glass as glass is a brittle material. At the moment the critical buckling force is reached the column does not deform as much but suffers from explosive brittle failure, because of this it is unpredictable and extremely dangerous. As a result of this brittle failure behavior we apply safety factors twice as high when designing with glass compared to other construction materials, leading to excessively large, heavy and costly elements. Research focused on creating load bearing glass colums has been conducted and has led to a few preceding glass columns. These columns did lack either mechanical or architectural desirability though. New research is being conducted into producing a glass load bearing column by laminating solid rods together, this research is very promising but is still limited by the boundaries generated as a result of this immense safety factors. Increasing the cross-sectional properties of such a column does increase the column’s resistance to buckling, but again leads to excessively large structural elements with increased weight and cost. But what if we can, rather than accepting the consequences of the high safety factors, reduce the safety factors by increasing the mechanical behavior during buckling, transforming the brittle and explosive failure into a more gradual and ductile failure. This thesis researches the potential of post-tensioning a bundled glass column in an attempt to transform the explosive brittle failure into a ductile mode of failure. In order to verify this behavior a total of six slender glass columns have been produced with a length of 2400 millimeters, three of these where loaded with around 3000 kilograms of prestress and all six were destructively tested. A prestressed member appears to be a more flexible element than a similar non-prestressed member and has post-breakage load bearing capabilities.Architecture and The Built EnvironmentBuilding Technolog
