CAMBRIDGE BAY, Nunavut, March 30 – In a snow-covered Canadian hamlet on the tip of the Arctic Ocean, there are two grocery stores, one sports arena and no doctors – a visit to one usually involves at least a two-hour plane ride south. Dentists stop by the community of 2,000 twice a year, and water is brought in by trucks. Giving birth often involves flying to a city several hours away, weeks before the baby is due.