White noise machines mask distracting sounds, improve privacy, and help people sleep; traditional models use a fan, while many newer ones generate sound electronically. A fan can do more than make noise: if it draws air through a filter, it can provide sound masking while removing smoke and infectious particles. A compact purifier may therefore be a more useful alternative for many settings where someone would otherwise use a white noise machine. One example costs $47, measures 6.5 inches across, and delivers 34 cubic feet of filtered air per minute at 45 decibels.
That airflow is modest compared with a larger purifier: an AirFanta 3Pro can clean about six times as much air at the same noise level, or twelve times as much at a louder 56 decibels. It costs $165, takes up more space, and may be less attractive. Even so, the small model can substantially reduce smoke particles. In a 10-by-10-foot room with an eight-foot ceiling and typical outdoor-air leakage of 0.5 air changes per hour, it would bring indoor particulate levels to about 16 percent of the outdoor level. Because AQI is not a linear scale, that reduction corresponds roughly to a change from AQI 200 to 72, or from 100 to 31.
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From August 2028, universities in England will pay £925 ($1,200) annually for each international student above an exemption threshold of 220, including current and new students. The government expects the levy to raise revenue for education, while university leaders warn it could strain finances and push up tuition fees. (africa.businessinsider.com)
The Pentagon is developing a plan for major U.S. bases to sustain essential operations independently for 90 days, including power, water, fuel, and communications. Separately, Britain is advising households to keep enough food, water, and cash for three days of disruption; officials say the efforts are not coordinated and do not signal an imminent war. (fortune.com)
“Buy, borrow and die” lets wealthy investors hold appreciating assets, borrow against them instead of selling, and pass them to heirs, who may receive a higher tax basis. The strategy can reduce capital-gains taxes while creating demand for loans secured by investments. (wsj.com)
The US fired an estimated 609 missile interceptors defending Israel from October 2023 through September 2026, including 186 SM-3s and 378 THAADs. The analysis estimates the interceptors cost $11 billion, exceeding Israel’s own use of ballistic-missile defenses. (stephensemler.com)
Microsoft is offering voluntary exits to 60,000 employees at level 70 or below in the U.S., India, Canada, and the UK. The program has prompted speculation that further layoffs are coming, but the post does not confirm that connection. (twitter.com)
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