Microbial processes in the Athabasca Oil Sands and their potential applications in microbial enhanced oil recovery.

The Athabasca Oil Sands are located within the Western Canadian Sedimentary Basin, which covers over 140,200 km(2) of land in Alberta, Canada. The oil sands provide a unique environment for bacteria as a result of the stressors of low water availability and high hydrocarbon concentrations. Understanding the mechanisms bacteria use to tolerate these stresses may aid in our understanding of how hydrocarbon degradation has occurred over geological time, and how these processes and related tolerance mechanisms may be used in biotechnology applications such as microbial enhanced oil recovery (MEOR). The majority of research has focused on microbiology processes in oil reservoirs and oilfields; as such there is a paucity of information specific to oil sands. By studying microbial processes in oil sands there is the potential to use microbes in MEOR applications. This article reviews the microbiology of the Athabasca Oil Sands and the mechanisms bacteria use to tolerate low water and high hydrocarbon availability in oil reservoirs and oilfields, and potential applications in MEOR.

Influence of colostrum deprivation and concurrent Cryptosporidium parvum infection on the colonization and persistence of Escherichia coli O157 : H7 in young lambs.

Escherichia coli O157 : H7 and Cryptosporidium parvum infections of man have been associated with direct contact with small ruminants. Colostrum protects neonates against gastrointestinal pathogens, and orphan lambs, which are common on petting farms, may be deprived of this protection. In a recent study, it was demonstrated that high shedding of E. coli O157 : H7 by an 8-week-old goat kid was associated with coincidental C. parvum infection. Furthermore, both pathogens were co-located in the distal gastrointestinal tract. It was hypothesized that colostrum deprivation and pre-infection with C. parvum predisposed young ruminants to colonization and increased shedding of E. coli O157 : H7. To test this, 21 lambs 5 weeks of age were divided into four groups as follows: (A) colostrum-deprived and inoculated with E. coli O157 : H7, (B) colostrum-deprived and inoculated with C. parvum and then E. coli O157 : H7, (C) conventionally reared and inoculated with E. coli O157 : H7, (D) conventionally reared and inoculated with C. parvum and then E. coli O157 : H7. C. parvum was detected between 8 and 12 days post-inoculation in most of the infected lambs. At 24 h post-inoculation with E. coli O157 : H7, all lambs were shedding between 5 x 10(4) and 5 x 10(7) c.f.u. E. coli O157 : H7 per gram of faeces. E. coli O157 : H7 was shed in higher numbers in the groups pre-inoculated with C. parvum, whether conventionally reared or colostrum-deprived. Interestingly, for the colostrum-deprived lambs on day 3, a significant difference in shedding of E. coli O157 : H7 was observed (P = 0.038), with the lambs inoculated with E. coli alone yielding higher counts than those pre-inoculated with C. parvum. From day 15 onwards, shedding of E. coli O157 : H7 was highest from the colostrum-deprived C. parvum-infected lambs, then (in descending order of shedding) the colostrum-deprived lambs, the conventionally reared lambs infected with C. parvum, and the conventionally reared animals. In total, four animals were euthanized, two at 24 h and two at 96 h post inoculation with E. coli O157 : H7 (two conventionally reared and two colostrum-deprived). All animals euthanized were from groups pre-inoculated with C. parvum prior to challenge with E. coli O157 : H7. On examination of tissues, in three of the four animals examined, multifocal attaching and effacing lesions were observed in the caecum, colon, rectum and at the recto-anal junction, and were confirmed by immunohistochemistry to be associated with E. coli O157 : H7.

Hypnosis as an adjunct to the administration of local anesthetic in pediatric patients.

This study investigates the acceptance of local anesthetic injection, utilizing hypnosis in twenty-nine children, ages four to thirteen years. Each subject was evaluated twice, once utilizing hypnosis before injection, and once without. A double blind research design was used to avoid effects of expectancy. Subjects in the study were videotaped during the procedure. Their behavior was rated independently by two pediatric dentists, using the North Carolina Behavior Rating Scale (NBRS). Transcutaneous pulse oximetry data were also recorded for each subject. The resulting data were evaluated for statistically significant differences between the two methods and for interrater reliability. Results showed no statistically significant differences in oxygen saturation due to hypnosis condition, order of treatment, sex, race, or age. Statistically significant differences were found in pulse rate and behavior, attributable to hypnosis condition and age, but not to sex, race, or order of treatment. Pulse rate decreased with hypnosis, as did crying. The hypnosis condition seemed to be more successful with younger children (four to six years old).

Vitamin supplementation in pregnancy.

The aim of the study was to investigate the extent and determinants of vitamin supplementation in early pregnancy. Some 246 women were recruited in the antenatal clinics of a major teaching hospital and asked to complete a brief questionnaire relating to sources of advice and details of diet and vitamin supplementation during the index pregnancy. Further information was abstracted from routine antenatal records. A total of fifty-seven women (23%) took some form of vitamin supplement during the index pregnancy. Factors which affected supplementation included advice received from diverse sources and whether or not the women took iron supplements. Somewhat surprisingly, supplementation was not affected by age, social class or reproductive history.