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Hot weather can increase the risk of natural disasters like droughts and wildfires, now, there is evidence extreme heat can increase harmful chemicals in the air.A study published recently in Science Advances looked at asphalt under different temperature conditions.“A main finding is that asphalt-related products emit substantial and diverse mixtures of organic compounds into the air, with a strong dependence on temperature and other environmental conditions,” says Peeyush Khare, a Yale chemical and environmental engineer and the lead author of the study, in a statement.The researchers took real-world samples of fresh road asphalt and put them in a controlled furnace with purified air. They heated the samples to temperatures between 104 and 392 degrees Fahrenheit, and measured the chemical components in the air.Total emissions nearly doubled when temperatures went from 104 to 140 degrees. At 104 degrees, 94 percent of the emissions measured were hydrocarbons.The group also exposed the asphalt samples to replicated solar heat, including UVA and UVB wavelengths, and found the rate of emission of potentially harmful chemicals increased. Showing that not only heat, but also solar radiation contributed to asphalt producing air pollution.Paved surfaces and roofs make up approximately 45% and 20% of surfaces in U.S. cities, respectively.Asphalt can be quite a bit hotter than the air around it, getting about 40 to 60 degrees warmer than the recorded air temperature.The researchers concluded that while policies and regulations have been put in place about car emissions and other forms of air pollution, asphalt should not be overlooked as a contributor.“It's another important non-combustion source of emissions that contributes to SOA (secondary organic aerosol) production, among a class of sources that scientists in the field are actively working to constrain better,” Drew Gentner, associate professor of chemical & environmental engineering, said. 1983

GUNNISON, Colo. – Linda Williams finds something beautiful in being disconnected.“We have not hooked up to the internet since we lived here," said Williams. "We’ve been here 30 years or so."She prefers connecting with the keys of her piano in her Gunnison, Colorado, home.The pandemic has forced her to connect with her students through the keys on her computer keyboard.“I love children. I love being around children," Williams said.A school district-issued internet hot-spot lets her teach virtually, but she wants the real thing.“We’re hoping for brick and mortar, as they say, because that’s the best way for learning," Williams said.Williams is a preschool special education teacher in the Gunnison Watershed School District, a rural school corporation with around 2,000 students.Geographically, the district reach is the second largest in Colorado."We are about the size of Rhode Island and Delaware combined," said Superintendent Leslie Nichols."The spread-out nature of our staff and our families have really brought internet access to the forefront of one of our biggest challenges," Dr. Nichols said.Dr. Nichols says most of the district is outside broadband and cellphone range. In the most rural parts, satellite internet is the only option.“It’s barely better than dial up," said Dr. Nichols.She says about 200 students have that problem.“It’s not like half my district is unable to access the internet, but those kids matter," Dr. Nichols said.The school year here will start in classrooms, but learning could go virtual.“All of those plans require good access to the internet," said Dr. Nichols.Last year, the district gave out close to 100 hotspots to students and staff dealing with connectivity issues at home. The hotspots run off cellphone service."I don't feel like it's the high school experience everyone else gets," said Gunnison High School Sophomore Nicholas Ferraro.Ferraro used a hot spot last school year when the pandemic forced learning online because his internet at home isn’t strong enough.“I’m not sure what the future is like, like if I'm going to go to school for the whole year next year," he said.Nationwide, a million school-aged children live in areas with limited access to the internet.“This country, in the 20th century, we electrified America and we got phone service to everyone in America. It’s past time that mentality with internet service it needs to happen," said Dr. Nichols.For those preparing to return to school, like teacher Linda Williams, the focus is on the connection in the classroom.“Learning and teaching is all about relationships that’s the foundation of it all. That’s one of the hard parts of online teaching," Williams said. 2700

Google chief executive Sundar Pichai appeared on Capitol Hill Wednesday where he faced questions from lawmakers on a number of issues, including data privacy, misinformation, a search product being developed for China, and allegations from Republicans that the search engine giant is biased against conservative users."All of these topics -- competition, censorship, bias, and others -- point to one fundamental question that demands the nation's attention: Are America's technology companies serving as instruments of freedom—or instruments of control?" House Majority Leader Kevin McCarthy said at the outset of the hearing, which was held by the House Judiciary Committee.McCarthy added, "[T]he Free World depends on a free Internet. We need to know that Google is on the side of the Free World, and that it will provide its services free of anti-competitive behavior, political bias, and censorship."The hearing, Pichai's first before Congress, came just a few months after a different attempt to get him to Capitol Hill turned so contentious that a Senate committee featured an empty chair in his place at a hearing.The House Judiciary Committee has questioned technology executives at hearings throughout the year, most recently Twitter (TWTR) chief executive Jack Dorsey in September.Those hearings have focused primarily on whether technology companies are biased against conservative users, but have touched on other issues.  1447

Grab your headphones and prepare to be blown away.NASA just announced it has heard the first-ever "sounds" of wind on Mars. But if you're expecting howling, swooshes and crackles, you're in for a surprise. These are vibrations, captured by NASA's InSight lander, which touched down on the Red Planet just last week. The craft will stay put until November 24, 2020, measuring quakes that happen anywhere on Mars.This week, the craft recorded something unexpected."InSight sensors captured a haunting low rumble caused by vibrations from the wind, estimated to be blowing between 10 to 25 mph (5 to 7 meters a second) on Dec. 1, from northwest to southeast," the agency said.An air pressure sensor and a seismometer recorded the noise through the vibrations in the air and vibrations around the aircraft "caused by the wind moving over the spacecraft's solar panels."This is the only time when vibrations from the lander will be recorded by the seismometer, since it will be moved by the craft's robotic armed and placed on the Martian surface, along with other instruments.The craft's landing comes as part of NASA's mission to explore the planet's deep interior.InSight lander's sensors are designed to detect quakes and air pressure through wind vibrations. The lander will measure whether tremors have the same effect as earthquakes. The Seismic Experiment for Interior Structure (SEIS), the seismometer, will use the vibrations to help scientists configure more about the planet's interior."Capturing this audio was an unplanned treat. But one of the things our mission is dedicated to is measuring motion on Mars, and naturally that includes motion caused by sound waves," Bruce Banerdt, the InSight principal investigator at NASA's Jet Propulsion Laboratory, said in a statement.To better hear this bass sound, it's better you bring out your headphones, or your subwoofer, as NASA suggested.You can hear the sounds here and listen to NASA's news telecon with a panel of scientists here.The-CNN-Wire 2011

GENEVA — The head of the World Health Organization says he will self-quarantine after being identified as a contact of a person who tested positive for COVID-19. Tedros Adhanom Ghebreyesus tweeted that he is “well and without symptoms” but will self-quarantine in “coming days, in line with WHO protocols, and work from home.” The U.N. health agency director-general chief has been at the forefront of the global response to the coronavirus pandemic. It has infected at least 46.5 million people and led to more than 1.2 million deaths, according to a count by Johns Hopkins University. 594

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