International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper discusses the telemetry processing and data verification performed by the SBV Processing, Operations and Control Center (SPOCC) located at MIT Lincoln Laboratory (MIT LL). The SPOCC is unique among the Midcourse Space Experiment (MSX) Data Processing Centers because it supports operational demonstrations of the SBV sensor for Space-Based Space Surveillance applications. The surveillance experiment objectives focus on tracking of resident space objects (RSOs), including acquisition of newly launched satellites. Since Space Surveillance operations have fundamentally short timelines, the SPOCC must be deeply involved in the mission planning for the series of observations and must receive and process the resulting data quickly. In order to achieve these objectives, the MSX Concept of Operations (CONOPS) has been developed to include the SPOCC in the operations planning process. The SPOCC is responsible for generating all MSX spacecraft command information required to execute space surveillance events using the MSX. This operating agreement and a highly automated planning system at the SPOCC allow the planning timeline objectives to be met. In addition, the Space Surveillance experiment scenarios call for active use of the 1 Mbps real-time link to transmit processed targets tracks from the SBV to the SPOCC for processing and for short time-line response of the SPOCC to process the track of the new object and produce new commands for the MSX spacecraft, or other space surveillance sensors, to re-acquire the object. To accomplish this, surveillance data processed and stored onboard the SBV is transmitted to the APL Mission Processing Center via 1 Mbps contacts with the dedicated Applied Physics Laboratory (APL) station, or via one of the AFSCN RTS locations, which forwards the telemetry in real-time to APL. The Mission Processing facility at APL automatically processes the MSX telemetry to extract the SBV allocation and forwards the data via file transfer over a dedicated fractional T1 link to the SPOCC. The data arriving at the SPOCC is automatically identified and processed to yield calibrated metric observations of RSOs. These results are then fed forward into the mission planning process for follow-up observations. In addition to the experiment support discussed above, the SPOCC monitors and stores SBV housekeeping data, monitors payload health and status, and supports diagnosis and correction. There are also software tools which support the assessment of the results of surveillance experiments and to produce a number of products used by the SBV instrument team to assess the overall performance characteristics of the SBV instrument.

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Colorectal cancer (CRC) is common in Ontario. This study described the processes of care following CRC resection, and identified CRC relapse from administrative data. Methods: CRC patients aged 18-80 from 1996-2001 with a colorectal resection were identified from the Ontario Cancer Registry. Linked discharge abstracts and physician billings were examined for physician visits, body imaging and endoscopy over the 5 year follow-up period. Administrative codes suggesting disease relapse were compared with patient charts. Results: Overall, 12,804 patients were identified and 8,804 had no evidence of relapse. Most (96.2%) patients had general practitioner follow-up, while 49.3% had medical oncology and 80.4% had general surgery follow-up. Greater than 90% of patients received endoscopy, while only 68.7% of patients received body imaging. Detecting disease relapse was 87.5% sensitive and 93.0% specific. Conclusions: There is potential for improving post-resectional follow-up in CRC patients. It is possible to detect relapse through administrative databases.

The public health significance of campylobacters lies in their role as enteropathogens of man. Zoonotic in origin, they are the most commonly reported bacterial cause of gastrointestinal infection in the developed world. Approximately 46,000 laboratory-confirmed cases are reported annually in England and Wales, and this figure underestimates community disease by a factor of eight. Infection is unpleasant and, whilst self-limiting, a tenth of cases require hospital admission for their illness. Sequelae such Irritable Bowel Syndrome, Reactive Arthritis and Guillain-Barré Syndrome compound the problem. Despite the significant public health burden posed by campylobacters, our understanding of the epidemiology of Campylobacter infection is limited. This deficiency relates to a combination of the natural history of the microorganism, the high disease incidence which exists and the epidemiological tools applied thus far to its study. In order to gain a better understanding of the epidemiology of Campylobacter infection the Campylobacter Sentinel Surveillance Scheme was conceived in 1998 and established in 1999. Through the integration of standardised epidemiological and microbiological data, it aimed to generate systematically new hypotheses for potential vehicles of infections, or transmission pathways, for campylobacteriosis. Twenty-two health authorities, representing all NHS regions at that time in England and in Wales and with a population of over 12 million people, participated in the study, which ran from May 2000 until April 2003. Standardised epidemiological data were captured on over 20,000 cases over the surveillance period and these were combined with microbiological data from detailed strain characterisation of patients‟ strains, referred at the same time. Case-case comparisons and disease determinant analysis were the epidemiological tools most commonly applied to the data. The research carried out by the candidate demonstrated that age, gender, ethnicity, occupation and socioeconomic status are major determinants for Campylobacter infection in England and Wales, and that variation in behaviour throughout the week also has a bearing on risk. It has shown that campylobacteriosis cannot be considered a single disease, as exposure differences exist in cases infected with different Campylobacter species or subspecies, and these differences can be confounded by foreign travel status. The fact that disease incidence amongst foreign travellers is country-specific suggests that the above exposure differences will be confounded further by travel destination. It has shown that outbreaks of campylobacteriosis occur more commonly than described previously, suggesting that an opportunity for furthering our understanding of infection is being missed. Finally, the dose-response relationship for Campylobacter infection has been investigated, highlighting potential implications for the design of future epidemiological studies. Policy makers should be aware that future case-control studies of Campylobacter infection will need to be larger or more complex, and hence more costly. Such costs should be weighed against the opportunity for a more accurate assessment of disease risk, leading to improved evidence-based policy development. Researchers should focus on assessing rapidly and by non-invasive means, previous exposure to campylobacters amongst healthy controls, improving further the accuracy of case-control studies, which remain the epidemiological method of choice for studying this disease. This study has demonstrated that the systematic collection of standardised epidemiological information on all cases of Campylobacter infection, reported from large, well defined populations over a prolonged period, coupled with detailed strain characterisation, can lead to public health gains.

The capacity of zoonotic pathogens to infect multiple hosts creates surveillance challenges but also provides opportunities to gather data from animal species that can be used to understand risks to human health. This thesis presents a conceptual and practical assessment of the utility of domestic dog serosurveillance for the detection and surveillance of two pathogens, influenza A and Leptospira spp. The first chapter gives a theoretical framework that can be used to explore the attributes of animal sentinels and assess their utility in different contexts. In subsequent chapters, this framework is applied in a practical assessment of the utility of a domestic dog serosurveillance approach for the detection and surveillance influenza A and Leptospira spp. at two sites in Africa. Two cross-sectional surveys of the avian and mammal populations at a site in Northern Cameroon were conducted in early 2006 to determine if H5N1 influenza A viruses had circulated in this area and in which species that presence could be detected. Serological and molecular evidence of extensive H5 virus circulation in the domestic duck population was identified. 47% of domestic ducks at the Maga site were cELISA positive for anti-influenza A antibodies and 20% were HI test positive against an H5N1 antigen. There was also evidence of exposure to H5 subtype viruses in the local dog and pig populations. At the Kibera site in Nairobi, a cohort study was established to carry out surveillance of influenza A and Leptospira spp. in the domestic dog population and cross-sectional surveys of the domestic poultry and rodent populations were completed. There was no indication of influenza A circulation in any of the animal species surveyed, indicating low risk of zoonotic influenza A infection in the human population of Kibera. In contrast, there was extensive molecular and serological evidence of the presence of Leptospira spp. in both the rodent and dog populations. 18% of 236 trapped rodents were PCR positive for kidney carriage of pathogenic leptospires and the estimated seroprevalence of anti- Leptospira antibodies in the dog population ranged from 5-36% during the course of the study, indicating high potential risk of leptospirosis infection in the human population. The results indicate that dog serosurveillance can be used as useful tool for the determination of broad-scale patterns of pathogen presence and relative levels of population exposure. However, there are limitations of the data that can be gathered from animal sentinels and the complexities introduced particularly by incomplete understanding of diagnostic test performance must be recognized. Animal sentinel surveillance may be of most use for addressing fundamental questions of what pathogens are present where. In the developing world particularly where disease burden data are still lacking, dog sentinel serosurveillance can provide essential baseline data that can be used to target future research and resource allocation.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

M.Ing. / Atmospheric turbulence (also referred to as optical or heat Scintillation, or heat shimmer) is a particular problem encountered in video surveillance, especially over distances where the target object focused on is over lkm in the distance. Images obtained from video surveillance are commonly required to be of a high quality for object identification and classification. Atmospheric turbulence causes degradation in the image quality through the blurring and a warping of the image, making object identification difficult. Algorithms have and still are being developed to suppress the image turbulence in digital video footage and enhance detail. There is a lack of reliable comparisons among algorithms to provide research direction, methods for identification of the best algorithms for particular applications, identification of useful image processing techniques and a full understanding of the problem. This need and lack of comparisons among the algorithms and atmospheric turbulence degraded videos is identified through the problem identification chapter. A literature study is undertaken in which the source of atmospheric turbulence and models are identified, image processing techniques discussed, filtering of electromagnetic waves reviewed, a review of some equipment, and a discussion of metrics. This is followed by the presentation of a number of atmospheric turbulence suppression algorithms developed by other authors. After a discussion of the algorithm implementations, the experimental design is described for algorithm image quality and performance investigation as well as the effect of optical filters. Experimental results are presented and discussed which provide repeatable results pertaining to the algorithms' image quality and processing requirements. The results allowed identification of the algorithms' strengths and weaknesses, how they compare, and their suitability for real and post processing environments. Efficient performing software components were also able to be identified, particularly Illuminance-Reflectance adjustment. The experiments and results provide a solution to this atmospheric turbulence comparison problem.