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SAN DIEGO (KGTV) — Nearly three-quarters of the students in San Diego County are currently learning from home, and those numbers don’t make a lot of sense to MIT professor Martin Bazant.Bazant is one of the creators of the COVID-19 Indoor Safety Guideline. The free online tool simulates the fluid dynamics of respiratory droplets in various kinds of rooms to show users the risk of different indoor environments.“If you run the numbers for a typical classroom, especially if the students and the teachers are wearing masks, then the amount of time in the room can be very significant,” Bazant said. “Essentially those people could spend a week in the classroom and not have a problem.”Bazant says the six-foot rule that has largely determined which businesses can stay open is overly simplistic. In some cases, he says the rule creates a false sense of security. In other situations, he says it causes the closure of businesses or schools that could safely operate.“If you place nursing home beds six feet apart in a shared room, they are absolutely not safe,” he said. But he said well-ventilated classrooms, with teachers and students in masks, are another story.“It's only the United States where we follow the six-foot rule. That's given by the CDC. The World Health Organization all along has been saying one meter, which is about three feet. If you simply followed the one-meter rule, all our schools would be open, as they are in most of the world right now,” he said.Bazant and his colleague John Bush said they set out to design a tool that would reveal the risk of transmission based on science, not guesswork.Users start by selecting a room type, like a classroom or an airplane. From there, they can control a wide array of variables to dial in the risk, like the room size, the ceiling height, and the ventilation and filtration systems.From there, users can further tune the model by human behavior. How many people are in the room? Are they whispering, shouting or singing? How many are wearing masks?Mask usage is a critical component, Bazant says. The model quickly reveals the challenges of maskless activities in rooms with poor ventilation. Put five people without masks in a 400 square foot room with closed windows, and it becomes unsafe after 33 minutes.Bazant says studies on super spreader events show in indoor environments, the distance from an infected person doesn’t matter. Infected droplets spread and mix throughout the room like second-hand smoke from a cigarette.But with masks trapping droplets and diverting them upwards like a chimney, an environment like an airplane could be safe for several hours, according to the model. With more than 95% of the passengers and crew wearing surgical masks, a Boeing 737 could support 200 people -- around full capacity depending on the configuration -- for 18 hours. 2850

SAN DIEGO (KGTV) — On Monday, a planetary sight unseen for nearly 800 years will captivate stargazers as Jupiter and Saturn create a celestial event known as the "Christmas Star."The two bright planets will align to create an even brighter display, culminating on the night of Monday, Dec. 21, according to NASA. While the two planets pass each other regularly, this year's event is so rare because not only is the distance between the planets so close but it's also occurring at night."You can imagine the solar system to be a racetrack, with each of the planets as a runner in their own lane and the Earth toward the center of the stadium," said Henry Throop, astronomer in the Planetary Science Division at NASA Headquarters in Washington. "From our vantage point, we’ll be able to be to see Jupiter on the inside lane, approaching Saturn all month and finally overtaking it on December 21."The closest alignment will last for a few days and appear just a tenth of a degree apart. On Monday, Jupiter and Saturn will appear so close that a pinkie finger at arm’s length will easily cover both planets.The planets haven't passed this closely in 400 years, and it's been nearly 800 years since this "Great Conjunction" has occurred at night, NASA says."Conjunctions like this could happen on any day of the year, depending on where the planets are in their orbits," said Throop. "The date of the conjunction is determined by the positions of Jupiter, Saturn, and the Earth in their paths around the Sun, while the date of the solstice is determined by the tilt of Earth’s axis. The solstice is the longest night of the year, so this rare coincidence will give people a great chance to go outside and see the solar system."HOW TO SEE ITIn San Diego County, viewers can see the planets without needing a telescope by looking toward the southwest horizon just after sunset, NASA says, but a pair of binoculars or a small telescope will only enhance the view. The best way to see the phenomenon is by finding an unobstructed view of the sky from say a park or field. The sight should even be viewable from most cities, but the site will only be visible after sunset for about one to two hours.To tell the two planets apart prior to Monday when they switch positions in the sky, Jupiter will look like a bright star and be easily seen, while Saturn will look slightly fainter and slightly above and to the left of Jupiter.For photographers, NASA recommends using a long exposure time to take in enough light as it gets dark. Both cell phone camera and DSLR camera users are encouraged to use a tripod to reduce any shaking during a long exposure.Cell phone users may even want to use "night mode" or a wide-angle lens if available. DSLR users may consider setting their focus to manual and leaving their aperture wide open to let in as much light as possible.Jupiter and Saturn should be bright enough to allow photographers to capture the planets without needing to zoom, NASA says. More of NASA's photography tips can be found online here. 3044

SAN DIEGO (KGTV) - Neglecting dental hygiene can not only impact a person's overall health but also their self-esteem. For many San Diegans, a lack of insurance means they don't see a dentist for years or even decades. “I’ve seen people in my practice in the private area that haven’t been to the dentist in 20 to 40 years," said Dr. Irvin Silverstein, director of the UCSD Student-Run Free Clinic Project.The student-run clinic has been working to fill the gap for low-income patients in San Diego for 20 years. “The biggest thing it has done is help meet the need in San Diego for a lot of underserved people. People think that underserved means homelessness or out on the streets, no. We see a lot of working poor," said Silverstein. RELATED: Making it in San Diego: How to deal with large medical billsPoor dentistry can lead to heart conditions, stroke, diabetes, and several other health problems. The four UCSD clinics are run by students and volunteer dentists, offering free care to the community:Downtown: Provides comprehensive dental care and oral health education to underserved San DiegansPacific Beach: Offers urgent dental care to patients in severe pain or with active infectionsLemon Grove: Offers dental care to Lemon Grove School District students Pre-K to 8th grade and their families Veterans Village: Offers free dental care to veterans participating in a 9-month long rehabilitation programDr. Silverstein says another issue they are seeing is retirees no longer having access to dental care because Medicare does not cover it. He says the American Dental Association (ADA) is acknowledging dentistry should be a benefit in Medicare; to at least get teeth cleaned twice a year and examined.Medicaid does provide some dental coverage, but there are limitations, and only 20 percent of dentists nationwide accept it, according to the Center for Healthcare Strategies, Inc. Dr. Silverstein says he often sees parents getting care for their children while neglecting their own. “They’ll put off going to the dentist, and by the time they realize they have a problem, it’s so expensive they don’t know what to do. And sometimes they even pull out their own teeth," said Dr. Silverstein.Other resources in the community provide affordable options for San Diegans:San Diego County Dental Health InitiativeGary and Mary West Senior Dental CenterAdditional clinicsDr. Silverstein hopes to open a fifth clinic in Normal Heights but says he will need more volunteer dentists and students to make it happen. Interested students do not have to attend UC San Diego to take part in the clinic. 2611

SAN DIEGO (KGTV) - Planned Parenthood officials say a recent act of vandalism at their Pacific Beach location will not "stop us from serving our patients."Red paint appeared to be thrown across the location's sign and windows on Mission Bay Drive sometime between late Sunday afternoon and Monday. A photo of crews cleaning the site was captured by a Reddit user and posted online here.In a statement to 10News, Planned Parenthood said the vandalism would not affect operations:"While we are disappointed by the recent vandalism to our health center, no attempt at intimidation will stop us from serving our patients. We've been a part of the fabric of this community for 55 years, and we'll be here for many more to come. Our patients can count on our doors to stay open, no matter what." 812

SAN DIEGO (KGTV) -- More rolling power outages are expected across San Diego as an intense heatwave bakes the county.SDG&E warned Monday that more rotating outages are likely across the region for the next few days."We certainly understand it's a pandemic and everyone is at home right now. We're working from home and schooling from home, and we totally get that, but everything we can possibly do to conserve any ounce of energy is going to help the collective right now," said Denice Menard communications manager for SDG&E.The California Independent System Operator runs the majority of the state's grid. The non-profit says the outages are necessary due to increased demand from the scorching temperatures, but some industry experts disagree."Asleep at the wheel might be a thought that comes to mind," said Bill Powers, Principal of Powers Engineering. Powers has worked on electrical systems for decades, and he's also testified as an expert on energy matters.Powers said there was nothing unusual about the heat."Those of us that watch this on a daily basis knew that Friday was a hot day, but it wasn't an atypical hot day. There was nothing special about Friday's temperature or electrical demand in terms of what we are capable of handling," said Powers.The last time California had rolling blackouts was in 2001. Powers believes the outages have more to do with how the power is managed rather than how much is available."That's due to their whole format where they determine who has the cheapest power in this moment, and then we will let that operate.If you have some units that take awhile to come up to speed that are higher cost, the system doesn't really work that well for that," said Powers.California's governor also called the outages unacceptable and promised a swift investigation."If they start operating the grid with a little bit of practical wisdom, they're not going to be any more blackouts. We have plenty of power, we have to use it in a smart way, that's what they get paid to do," said Powers.The outages usually last an hour and happen between 2 pm and 10 pm.No one from the California ISO was available for comment Monday. 2174

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