The importance of microbial mats for dolomite formation in the Dohat Faishakh sabkha, Qatar

The Dohat Faishakh sabkha in Qatar is one of the rare modern environments where it is possible to study the formation of dolomite, a mineral whose origin has been long debated. In previous studies, dolomite formation in this area was considered to be the result of a penecontemporaneous replacement of aragonite, occurring in the presence of Mg-rich evaporated pore-waters. However, a re-investigation of the sabkha revealed that dolomite is not forming exclusively under the evaporitic conditions that characterize the supratidal zone, but also in microbial mats that colonize the lower intertidal zone, indicating that evaporated pore-waters are not a strict requirement for the mineralization process. Moreover, in the supratidal zone, portions of the sediment that are rich in dolomite are also relatively richer in organic material, which derives from partially degraded microbial mats buried in the sediments. Extracellular polymeric substances (EPS) that constitute microbial mats are recognized as an important component for the formation of Mg-rich carbonates. The presence of living and decaying microbial mats comprising EPS, rather than a replacement process, may be the key factor for dolomite formation in the Dohat Faishakh sabkha.Swiss National Science Foundatio

Periodontal disease and atherosclerosis from the viewpoint of the relationship between community periodontal index of treatment needs and brachial-ankle pulse wave velocity

BACKGROUND: It has been suggested that periodontal disease may be an independent risk factor for the development of atherosclerosis. However, the relationship between periodontal disease and atherosclerosis has not been fully elucidated. This study aimed to assess the effects of periodontal disease on atherosclerosis. METHODS: The study design was a cross-sectional study. Subjects were 291 healthy male workers in Japan. We used the Community Periodontal Index of Treatment Needs (CPITN) score, average probing depth and gingival bleeding index (rate of bleeding gums) to assess the severity of periodontal disease. We also used the Brachial-Ankle Pulse Wave Velocity (baPWV) as the index for the development of atherosclerosis. RESULTS: The unadjusted odds ratio (OR) of atherosclerosis in relation to the CPITN score was 1.41 [95% CI: 1.16–1.73]. However, after adjustment for age, systolic blood pressure and smoking, the CPITN score had no relationship with atherosclerosis (adjusted OR: 0.91 [0.68–1.20]). CONCLUSION: Our results show no relationship between mild periodontal disease and atherosclerosis after appropriate adjustments

Randomized pilot study to disseminate caries-control services in dentist offices

BACKGROUND: To determine whether education and financial incentives increased dentists' delivery of fluoride varnish and sealants to at risk children covered by capitation dental insurance in Washington state (U.S.). METHODS: In 1999, 53 dental offices in Washington Dental Service's capitation dental plan were invited to participate in the study, and consenting offices were randomized to intervention (n = 9) and control (n = 10) groups. Offices recruited 689 capitation children aged 6–14 and at risk for caries, who were followed for 2 years. Intervention offices received provider education and fee-for-service reimbursement for delivering fluoride varnish and sealants. Insurance records were used to calculate office service rates for fluoride, sealants, and restorations. Parents completed mail surveys after follow-up to measure their children's dental utilization, dental satisfaction, dental fear and oral health status. Regression models estimated differences in service rates between intervention and control offices, and compared survey measures between groups. RESULTS: Nineteen offices (34%) consented to participate in the study. Fluoride and sealant rates were greater in the intervention offices than the control offices, but the differences were not statistically significant. Restoration rates were lower in the intervention offices than the control offices. Parents in the intervention group reported their children had less dental fear than control group parents. CONCLUSION: Due to low dentist participation the study lacked power to detect an intervention effect on dentists' delivery of caries-control services. The intervention may have reduced children's dental fear

On the visual detection of non-natural records in streamflow time series: challenges and impacts

Large datasets of long-term streamflow measurements are widely used to infer and model hydrological processes. However, streamflow measurements may suffer from what users can consider anomalies, i.e. non-natural records that may be erroneous streamflow values or anthropogenic influences that can lead to misinterpretation of actual hydrological processes. Since identifying anomalies is time consuming for humans, no study has investigated their proportion, temporal distribution, and influence on hydrological indicators over large datasets. This study summarizes the results of a large visual inspection campaign of 674 streamflow time series in France made by 43 evaluators, who were asked to identify anomalies falling under five categories, namely, linear interpolation, drops, noise, point anomalies, and other. We examined the evaluators' individual behaviour in terms of severity and agreement with other evaluators, as well as the temporal distributions of the anomalies and their influence on commonly used hydrological indicators. We found that inter-evaluator agreement was surprisingly low, with an average of 12 % of overlapping periods reported as anomalies. These anomalies were mostly identified as linear interpolation and noise, and they were more frequently reported during the low-flow periods in summer. The impact of cleaning data from the identified anomaly values was higher on low-flow indicators than on high-flow indicators, with change rates lower than 5 % most of the time. We conclude that the identification of anomalies in streamflow time series is highly dependent on the aims and skills of each evaluator, which raises questions about the best practices to adopt for data cleaning.</p

Examining the experiences of college women about body modification : searching for the "I" in tattoo

Access to thesis permanently restricted to Ball State community only.The tattooing culture has been associated with negativity and danger for much of the Western culture’s history (Atkinson, 2003; Caplan, 2000; DeMello, 2000). Recently,a shift has occurred in which the practice of tattooing has become a method of expression and a tool in illustrating one’s identity. Despite this transition, there continues to be hesitation against the tattooing culture regarding acceptance in the collegiate and professional setting (Manuel & Sheehan, 2007). The strongest hesitation seems to be toward females with tattoos based on our society’s beauty ideals and expectations of feminine expression and behavior (Atkinson, 2002; Atkinson, 2003). Through means of qualitative methodology, semi-structured interviews were conducted with seven tattooed, female, undergraduate students. Their experiences were transcribed and the data were analyzed using coding (Strauss and Corbin, 1990) to identify prominent themes among the participants. The women shared their experiences of why they chose tattooing to express their ideas and shared the meaningful stories that inspired the art they have or will be getting. They also shared many stories of disapproval or mistreatment as a result of being a tattooed female. There was particular connection between disapproval and generational beliefs as well as religious beliefs. The college environment was an overall positive environment for the women to be, however stories were shared of mistreatment or judgment from the classroom or particular areas of study. Suggestions were presented for those who work in the college setting with students who might be of this sub-population.Thesis (M.A.)Department of Educational Studie