Cryptosporidium spp. is an oocyst-forming apicomplexan protozoan, which infects humans and a large variety of animals. Several species and genotypes are potentially zoonotic and ruminats are considered as an important source of infection. Pre-weaned calves are major hosts for zoonotic C. parvum, and show higher rates of infection than post-weaned or adult animals. Cryptosporidium infection has been demonstrated in a wide variety of wild animals, which may co tribute to environmental contamination. In sub-Saharan Africa, where the HIV infection prevalence is the highest in the world, high incidence of severe and even fatal Cryptosporidium infection have been reported in humans. This study investigated the epidemiology of Cryptosporidium spp. simultaneously in wildlife, indigenous cattle and young children living at the wildlife, livestock and human interface on the western boundary of the Kruger National Park (KNP) in Mpumalanga Province, South Africa. Initially, a pilot study was carried out to assess the zoonotic or anthroponotic importance of Cryptosporidium in diarrhoeic children in South Africa, representing the human group most likely to be infected. This geographically broad study involved hospitals from four provinces in South Africa. Stool samples from hospitalized diarrhoeic children from 0-1 year of age were analysed by microscopy (modified Ziehl-Neelsen (MZN) acid-fast staining) and molecular techniques: polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) and sequencing. An overall prevalence of Cryptosporidium infection of 12.2% was revealed, mainly involving species of anthroponotic origin, such as C. hominis (76%) and C. parvum of anthroponotic nature (20%). Only one species of uncertain zoonotic importance (C. meleagridis) was detected in this study. These findings were in accordance with reports from sub-Saharan Africa (including South Africa), where anthroponotic species of Cryptosporidium were responsible for most infections in humans. The study then concentrated on the public health importance of cryptosporidiosis at the wildlife/livestock/human interface of the KNP. Cryptosporidium oocysts were detected in elephant, impala and buffalo samples collected in three different study areas of the KNP; two located close to the boundaries of the KNP and a third one in the centre of the KNP. The MZN staining technique and an immunofluorescent antibody (IFA) test were applied to identify oocysts from faecal samples. The prevalence detected with MZN was higher than that detected with IFA, however both tests found a higher prevalence in elephants (25.8% and 4.2%, respectively) compared to the other species. The prevalence of Cryptosporidium in buffalo was 5.5% and 1.4% with MZN and IFA, respectively, and 4.2% and 1.8% respectively in impala. In the two study areas adjacent to the fence of KNP, the combined prevalence was significantly higher compared to the area in the centre of the KNP. The agreement between the MZN staining technique and the IFA test was assessed for each wildlife species; the estimates of kappa suggested moderate agreement in buffalo and impala and fair to poor agreement in elephant. The above results of were analysed further by the use of molecular techniques in order to reveal the species and genotypes of the parasite in wildlife and in addition faecal samples collected from post-weaned calves. A questionnaire was also conducted among farmers to investigate observed contacts between cattle and wildlife species in grazing areas outside and inside the KNP. Four of the 241 wildlife samples were PCR-positive (2.8% each in impala and buffalo and of 0.0% in elephant) and sequencing revealed the presence of C. ubiquitum in two impala and one buffalo and C. bovis in one buffalo. Cryptosporidium ubiquitum has been commonly found in a large number of animals, including humans. Among calf samples, 8% (4/51) were PCR-positive and were identified as C. andersoni (2/4) and C. bovis (2/4). The probability of contact between cattle and wildlife outside the KNP, observed by farmers, was higher for buffalo (Pr=0.6) and impala (Pr=0.46) than for elephant (Pr=0.04). This suggests that the detection of C. bovis in both cattle and buffalo might be due to direct or indirect contact between these two species. The detection of C. ubiquitum in wildlife, with its zoonotic potential, suggests that Cryptosporidium may be of public health concern for people living at the interface. We further investigated the prevalence of Cryptosporidium infection in cattle and humans, this time targeting younger (pre-weaned) calves and children. Children <5 years were sampled at six rural clinics within the same interface and stool samples were screened by the MZN staining technique. All MZN-positive and suspicious samples of children and samples of 36 calves within the age of 0-4 months were analysed by nested PCR. Eight of the 143 children (5.6%) were positive on PCR, and sequencing identified predominantly C. hominis, while one sample was identified as C. meleagridis. Eleven of the 36 calf samples (30.5%) were PCR-positive and were identified as C. bovis and C. ryanae. Due to limited resources, molecular analysis could not be performed on more samples. Variables such as source of drinking water, age and contact with animals for children, were analysed as potential risk factors for humans and cattle; however, none were statistically significant. In conclusion, the prevalence of Cryptosporidium detected in human and wildlife was low compared to that reported in other studies in Africa. The species and genotypes detected in humans were predominantly of anthroponotic nature; however, the isolation of C. Ubiquitum from buffalo and impala shows that at least one species of zoonotic importance is present at the wildlife/livestock/human interface. The prevalence of HIV/AIDS in our study area is one of the highest worldwide; therefore the potential public health importance of this parasite should be investigated further. / Thesis (PhD)--University of Pretoria, 2013. / gm2013 / Production Animal Studies / unrestricted

The aim of this project was to develop and evaluate an interactive Augmented Reality interface for teaching children aged 8 to 15 about biological systems present in the human body. The interface was de- signed as one component of a “human body scanner” exhibit, which is to be featured at the ScienceAlive! Science Centre. In the exhibit, the interface allows visualization and interaction with the body systems while being moved across a human male mannequin named BRET. Prior research has shown that Augmented Reality, Visualization applications, and games are viable methods to teach biology to university aged users, and Augmented Reality and interactive systems have been used with children and learning biology as well. BRET went through three iteration phases, in the first phase, prototypes were evaluated by ScienceAlive! and designs and interactions were implemented, while the use of Augmented Reality through a transparent display was rejected. Iteration two included integration of the non-transparent touch display screen and observational evaluation of six children from 9 to 15 years old. This evaluation resulted in design and interaction changes. Iteration three was the last iteration where final interface and interaction modifications were made and re- search was conducted with 48 children from the ages 8 to 15. This was to determine whether learning, fun, and retention rates were higher for children who interacted with BRET versus those who watched video clips, or read text. Each child used one learning method to learn the three different body systems: skeletal, circulatory, and digestion. The results of the final evaluation showed that overall there was no significant difference in the children’s rating of fun or the amount of information they retained between the different learning methods. There was a positive significant difference between some of the expected fun scores and the actual fun scores. It was also found that learning with text was higher than the interactive condition but there was no differences between learning with video and interaction, or with text and video.

No description available.

The current study examined specific aspects of human factors involved in driving a vehicle with a modified Drive-by-Wire (DBW) control system. A DBW system is an electro-mechanical system which controls the primary operations of a vehicle such as steering, acceleration, and braking using a controller such as a joystick. Designing a human interface system for a DBW system involves three main phases in the human factors design process namely user centric/ergonomic design conception, building a prototype and validating the prototype based on human factor considerations. The main objective and focus of this research is to conceptualize a more ergonomic DBW control interface based on human participant evaluations completed in a virtual reality driving simulator equipped with DBW controls. A secondary consideration is the gathering of data for the preparation of a future driver training course. The driving characteristics of 30 participants consisting of 3 different groups, ages 18-64, ages 65+,and people with disabilities were evaluated while driving with three different controllers: a joystick, a reduced effort steering wheel plus gas-brake lever combination (GB), and conventional vehicle controls (no Drive-by-Wire or NDBW), which included foot pedals and a steering wheel. The participants were required to drive through different scenarios such as mountain, city, and highway roads, in order to obtain user capabilities related to the steering, accelerating, braking, and compliance with traffic rules. To examine the steering lane data obtained from the simulator, percent error in lane deviation was calculated and presented against time. The results indicated that the joystick was the most difficult to drive on a straight road. The GB controller was easier to control on straight path maneuvers than the joystick, but it had an over-steering tendency at curves while the joystick was better at curves. To examine group differences of different variables, a one-way analysis of variance (ANOVA) was performed. Results showed that lane position variation, reaction time to brake, reaction distance and stopping distance had significance among variables such as maximum vehicle speed, improper space cushions, and missed turn signals, etc. Understanding the above characteristics can largely help in the development of a DBW interface system that heavily weighs human factors.

Atualmente Jogos Eletrônicos possuem uma grande relevância no setor econômico, na computação e na pesquisa acadêmica, não se limitando apenas a aplicações de entretenimento. Na busca por inovação na jogabilidade e nas interfaces interativas dos jogos eletrônicos, a Realidade Aumentada é uma das novas fronteiras a serem exploradas. Este trabalho apresenta a pesquisa, desenvolvimento e teste de uma infra-estrutura, denominada Robot ARena, para o desenvolvimento de jogos inovadores utilizando a Realidade Aumentada e as novas interfaces que esta tecnologia possibilita. Baseada em interfaces horizontais e composta por elementos de hardware e software, a Robot ARena possui uma arquitetura flexível que possibilita diversas formas de interação e de visualização. Outro aspecto previsto neste projeto é o controle e a comunicação de robôs, que podem ser utilizados como avatares nos jogos. Os conceitos envolvidos, Jogos Eletrônicos e Realidade Aumentada Espacial, são discutidos, bem como os trabalhos que inspiraram alguns dos aspectos desta infra-estrutura. Um protótipo da Robot ARena foi implementado e testado e utilizado no desenvolvimento de dois protótipos de jogos, FootBot ARena e TanSpace, que trazem novos desafios a esta infra-estrutura, como explorar a influência de objetos virtuais aos objetos reais e a aplicação de interfaces tangíveis. / Nowadays Electronic Games have a great importance in the economic sector, in computing and in academic research, not limited only to entertainment applications. In the search for innovation in gameplay and in the interactive interfaces of electronic games, Augmented Reality is one of the new frontiers to be explored. This work presents the research, development and testing of an infrastructure, called Robot ARena, for the development of innovative games using the Spatial Augmented Reality and new interfaces that this technology allows. Based on horizontal interfaces with elements of hardware and software, Robot ARena has a flexible architecture that enables different ways of interaction and visualization. Another aspect planned for this project is the control and communication of robots, which can be used as avatars in games. The concepts involved, Electronic Games and Spatial Augmented Reality, are discussed, as well as the work that inspired some aspects of this infrastructure. A Robot ARena prototype was implemented, tested and used in the development of two games prototypes, FootBot ARena and TanSpace, which brings new challenges to the infrastructure, such as exploration of the influence of virtual objects in real objects and the application of tangible interfaces.

Atualmente Jogos Eletrônicos possuem uma grande relevância no setor econômico, na computação e na pesquisa acadêmica, não se limitando apenas a aplicações de entretenimento. Na busca por inovação na jogabilidade e nas interfaces interativas dos jogos eletrônicos, a Realidade Aumentada é uma das novas fronteiras a serem exploradas. Este trabalho apresenta a pesquisa, desenvolvimento e teste de uma infra-estrutura, denominada Robot ARena, para o desenvolvimento de jogos inovadores utilizando a Realidade Aumentada e as novas interfaces que esta tecnologia possibilita. Baseada em interfaces horizontais e composta por elementos de hardware e software, a Robot ARena possui uma arquitetura flexível que possibilita diversas formas de interação e de visualização. Outro aspecto previsto neste projeto é o controle e a comunicação de robôs, que podem ser utilizados como avatares nos jogos. Os conceitos envolvidos, Jogos Eletrônicos e Realidade Aumentada Espacial, são discutidos, bem como os trabalhos que inspiraram alguns dos aspectos desta infra-estrutura. Um protótipo da Robot ARena foi implementado e testado e utilizado no desenvolvimento de dois protótipos de jogos, FootBot ARena e TanSpace, que trazem novos desafios a esta infra-estrutura, como explorar a influência de objetos virtuais aos objetos reais e a aplicação de interfaces tangíveis. / Nowadays Electronic Games have a great importance in the economic sector, in computing and in academic research, not limited only to entertainment applications. In the search for innovation in gameplay and in the interactive interfaces of electronic games, Augmented Reality is one of the new frontiers to be explored. This work presents the research, development and testing of an infrastructure, called Robot ARena, for the development of innovative games using the Spatial Augmented Reality and new interfaces that this technology allows. Based on horizontal interfaces with elements of hardware and software, Robot ARena has a flexible architecture that enables different ways of interaction and visualization. Another aspect planned for this project is the control and communication of robots, which can be used as avatars in games. The concepts involved, Electronic Games and Spatial Augmented Reality, are discussed, as well as the work that inspired some aspects of this infrastructure. A Robot ARena prototype was implemented, tested and used in the development of two games prototypes, FootBot ARena and TanSpace, which brings new challenges to the infrastructure, such as exploration of the influence of virtual objects in real objects and the application of tangible interfaces.

The development of high quality software the first time, greatly depends upon the ability to judge the potential quality of the software early in the life cycle. The Software Engineering Research Center design metrics research team at Ball State University has developed a metrics approach for analyzing software designs. Given a design, these metrics highlight stress points and determine overall design quality.The purpose of this study is to analyze multiple software releases of the Advanced Field Artillery Tactical Data System (AFATDS) using design metrics. The focus is on examining the transformations of design metrics at each of three releases of AFATDS to determine the relationship of design metrics to the complexity and quality of a maturing system. The software selected as a test case for this research is the Human Interface code from Concept Evaluation Phase releases 2, 3, and 4 of AFATDS. To automate the metric collection process, a metric tool called the Design Metric Analyzer was developed.Further analysis of design metrics data indicated that the standard deviation and mean for the metric was higher for release 2, relatively lower for release 3, and again higher for release 4. Interpreting this means that there was a decrease in complexity and an improvement in the quality of the software from release 2 to release 3 and an increase in complexity in release 4. Dialog with project personnel regarding design metrics confirmed most of these observations. / Department of Computer Science

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No description available.

一個進步的文明城市，公共區域建築物內皆設有無障礙空間設施以照顧社會弱勢的族群，使這些族群享有同等使用社會資源的權利。同樣的，在電腦科技日新月異的當下，某些人在享受科技帶來的資訊及便利，某些人則因使用介面的障礙而無法同等享受其便利，因而形成人機介面所造成的數位障礙。 電腦虛擬世界和現實世界本是涇渭分明，由於電腦科技的進步及人們的需要在現實世界中擴增虛擬訊息成為可能。憑藉擴增實境的應用及使用者互動方面的研究，來改善人機介面造成的數位障礙，讓更多不同族群的人享有資訊科技帶來的好處。 上述的數位障礙中，最普遍的族群是幼年與年長者，其通常亦是最需要醫療照護的族群；因此本研究以一個醫療衛教為主題實例，著重預防重於治療的前提，研究醫護人員如何讓一般民眾了解特定疾病或傷害的基本知識；用於在平時或治療前、治療後的醫病溝通，欲有助於減少特定疾病引發一連串成本較高的治療程序，進而減少醫療資源的使用，使全民健保預算有效運用。 人機介面是為溝通真實世界與電腦虛擬世界，因此在本研究中以實例運用目前主流的圖形使用者介面(Graphic Uesr Interface, GUI)的操作模式下，提供以有形使用者介面(Tangible User Interface, TUI)，以一個腦部虛擬實境的衛教應用，加上擴增實境技術，將教材內容具象化、內容可視化、可操作化，建立一個數位弱勢族群(如老人、小孩)易於使用的互動介面環境。