Drivers of Mercury Cycling in the Rapidly Changing Glacierized Watershed of the High Arctic's Largest Lake by Volume (Lake Hazen, Nunavut, Canada).

Across the Arctic, glaciers are melting and permafrost is thawing at unprecedented rates, releasing not only water to downstream aquatic systems, but also contaminants like mercury, archived in ice over centuries. Using concentrations from samples collected over 4 years and calibrated modeled hydrology, we calculated methylmercury (MeHg) and total mercury (THg) mass balances for Lake Hazen, the world's largest High Arctic lake by volume, for 2015 and 2016. Glacial rivers were the most important source of MeHg and THg to Lake Hazen, accounting for up to 53% and 94% of the inputs, respectively. However, due to the MeHg and THg being primarily particle-bound, Lake Hazen was an annual MeHg and THg sink. Exports of MeHg and THg out the Ruggles River outflow were consequently very low, but erosion and permafrost slumping downstream of the lake increased river MeHg and THg concentrations significantly before entering coastal waters in Chandler Fjord. Since 2001, glacial MeHg and THg inputs to Lake Hazen have increased by 0.01 and 0.400 kg yr-1, respectively, in step with dramatic increases in glacial melt. This study highlights the potential for increases in mercury inputs to arctic ecosystems downstream of glaciers despite recent reductions in global mercury emissions.

Wavelet time entropy, T wave morphology and myocardial ischemia.

Using wavelets, we computed the entropy of the signal at various frequency levels (wavelet time entropy) and, thus, find an optimal measure to differentiate normal states from ischemic ones. This new indicator is independent from the ST segment and yet provide a conclusive detection of the ischemic states.

Process and outcome in a hostel outreach program for homeless clients with severe mental illness.

A longitudinal study followed 55 homeless and severely mentally ill clients of a hostel outreach program to assess outcomes and their relationship to program elements. Results at 18-month follow-up indicated that, despite chronic histories of transiency and shelter use, housing stability had been achieved, and that initial gains in social functioning and symptom reduction had been increased. Development of a strong working alliance proved a key program element in the findings.

Effects of CO2 laser irradiation on tooth-root cementum.

With the aging of the American population and the endemic problem of gingival recession, patients will inevitably suffer from greater exposure of root surfaces and therefore will be more likely to develop root caries. The treatment of root caries is often frustrating. Traditional biomaterials used for the restoration of enamel caries have been less than satisfactory when margins of a cavity are adjacent to cementum. Although topical fluoride gels, toothpastes, and rinses have been used to prevent or to inhibit the development of root caries, there is a problem of access to the proximal surfaces. Consequently, the development of better methods to facilitate the prevention of root caries has become an important issue in dentistry.

The hostel outreach program: assertive case management for homeless mentally ill persons.

OBJECTIVE: This study measured the impact of an assertive case management program for psychiatrically disabled homeless persons in metropolitan Toronto. It was hypothesized that the program would improve residential stability, reduce psychiatric symptoms, improve social functioning, improve social networks, and increase use of appropriate services. METHOD: For 59 clients admitted to the program, assessments for the nine-month period before program entry were completed and were repeated nine months later. The Brief Psychiatric Rating Scale and a version of the Scale for Level of Functioning were the main measures of outcome. RESULTS: At follow-up significant improvements in residential stability and reductions in psychopathology were demonstrated. Improvements in social functioning and increases in social network size were significant. Although no baseline data about service use were collected, clients used basic support services during their first nine months in the program. CONCLUSIONS: The success of the program demonstrates that a difficult-to-treat patient population can be helped in a humane fashion if trained personnel are available.