Soon I was obsessing over my sleep and activity scores. The reports were generally positive except for one: heart rate variability, or HRV. That's a measure of how much the time between heartbeats changes. Every morning, in bright red, my ring's app singled out HRV and told me: Pay attention. That didn't sound good, although I had no idea why. Before wearable fitness watches, rings and bracelets became so common and started including HRV as a data point, I had never heard of it.
Oura Health Oy, the maker of the Oura health and fitness ring, is raising $875 million in a new Series E financing round valuing it around $10.9 billion, according to a new report from Bloomberg. The round, which is expected to close by the end of the month, would double the company's $5 billion valuation from its Series D round announced last December. The report notes that the Series E round could still exceed $900 million.
According to the study published in the Nature journal, the team of researchers analysed how thermoelectricity, the movement of electrons from hot to cooler regions, can be harnessed using their elastic polymer composite. They reported that the material can stretch to 150 percent of its initial length and withstand strains of more than 850percent. The fact that it remains stretched under stress means it remains in close contact with the skin, and that makes power generation more efficient, the researchers said.
