沈阳人体呼吸系统模型（浮雕）(浙江超声引导下腹腔穿刺技能训练模型) (今日更新中)

As the debate over arming teachers in schools reverberates across the country, Kansas is doubling down on the idea.A new bill would not only authorize the arming of Kansas school staff, it would hold schools responsible if a shooting were to occur and the teachers and staff present were not allowed to be armed.Here's the exact wording?from House Bill 2789:"In any action against a unified school district arising out of acts or omissions regarding the possession or use of firearms on the premises of such school district, there shall be a rebuttable presumption of negligence on the part of such school district when it is shown by evidence that such school district did not authorize any employee of such school district, other than school security officers, to carry concealed handguns..."The House bill is causing some serious contention in the Kansas state capitol. During a House Insurance Committee hearing on Tuesday, Rep. Blake Carpenter, one of the bill's authors, quoted the movie "American Sniper" and said violence in school was a matter of "when" and not "if.""It's not if our kids will be killed; it is when they will be killed and what we are doing to prevent it," he said,?according to the Kansas City Star.CNN has reached out to Carpenter for comment.The bill has received significant pushback. A group of protesters was present at Tuesday's hearing, and Rep. Brett Parker, a Democratic opponent of the bill, shared a photo of stacks of papers he says are written testimonies against it.Kansas teachers?are technically already allowed by state law to carry guns on public school campuses as long as they have a permit and meet any school-specific requirements. But according to the Kansas City Star the 2013 legislation caused problems with insurance providers for some of the state's school districts, who refused to extend coverage because of the liability of armed staff.As a result, some districts put their own policies in place, overriding the law and disallowing the concealed carry of weapons on school property.The bill currently before the House committee also addresses this by forbidding insurance companies from refusing coverage just because a school district allows teachers and staff to be armed."No insurance company shall charge unfair discriminatory premiums, policy fees or rates for, or refuse to provide, any policy or contract of real or personal property insurance, liability insurance or policy containing liability coverage for any unified school district solely because such school district authorizes employees of such school district to carry concealed handguns on the premises of schools and attendance centers operated by such school district..." the bill states. 2742

As the COVID-19 pandemic progresses, researchers say it is important to track how the coronavirus mutates because it could affect the efficacy of a vaccine.Like all living cells, viruses evolve their chemical make-up changes. In viruses like the flu, that happens frequently, which is why every year there is a new vaccine to treat whatever strain is expected to circulate. With COVID-19, however, those mutations happen much slower, according to research out of Arizona State University.“One of the things we’re still keeping an eye on is the evolution of this virus because that virus is still around in the community,” said Dr. Efrem Lim, an assistant professor at ASU. “Everyone is coming in blind to this. This is a novel virus. This isn’t something we have seen before.”In March, Arizona State University played host to our country’s fourth COVID-19 case. As soon as it was detected, Dr. Lim started studying how the virus mutates and sent his findings to the World Health Organization. It's something that still continues to this day.“This virus, overall, mutates pretty slowly, which is a good thing,” said Dr. Lim. “However, we can have instances where the virus can have very large, dramatic, mutations, such as deletions in the genome.”While rare, Dr. Lim says those mutations can be significant as it changes how the virus acts inside the body.Currently, scientists are focusing much of their efforts on identifying ways to eliminate the function of the spike protein in COVID-19, as it is the way the virus binds to our cells and infects them (spike proteins are the stalks that protrude from the center of the virus that make it so recognizable).“It is very good news that the virus is not changing rapidly,” said ASU virologist Dr. Brenda Hogue. “We will have to see over time, as the virus continues to circulate, as we put a vaccine into play, whether or not there will be any issues.”Dr. Lim says right now there does not appear to be any issues because the virus mutates slowly, but he adds it could adapt to a vaccine once one begins to circulate.He says more testing needs to be done to determine that, however. 2140

As we shield ourselves in any way possible from the novel coronavirus, there are some parts of the country handling social distancing better than others.“This is a public health problem; it’s not a private health problem,” explained Dr. Bhaskar Chakravorti, who leads the Fletcher Institute for Business at Tufts University. “If I get sick, I could make three other people sick.”Over the past few months, Dr. Chakravorti and his colleagues have been analyzing mobility data from across the country.What did he and his team discover?The top three states who were practicing social distancing the most were New York, New Jersey and Massachusetts. Nebraska, South Dakota, Arizona were among the worst when it came to practicing social-distancing procedures. Dr. Chakravorti says that has led to higher contagion rates in those areas.“In this post-pandemic moment, each state is going in somewhat a different direction as far as how it's managing the pandemic,” he added.In bigger cities with higher rates of infections, the study found that people responded better to restrictions because they could see the impact the coronavirus was having around them. Dr. Chakravorti hopes public health officials use his findings to make more uniform policies nationwide.“This whole issue of COVID has become a political issue, so even the act of wearing a mask has become a political statement,” he said. “You never want to mix politics with anything. You definitely don’t want to mix it with public health. That’s a dangerous combination.” 1534

As the Carr Fire becomes the seventh most destructive wildfire in California's history, renowned chefs Guy Fieri and José Andrés are doing everything they can to help feed the evacuees and first responders."My team and I got involved. My son and his buddies, and a bunch of my buddies, loaded up the caravan from wine country and drove four hours up here," Fieri said."We are just working arm-in-arm with the Salvation Army, local chefs, residents and everybody helping out all of the evacuees."More than 12,300 firefighters are battling 15 wildfires burning across California. In total, these fires have burned more than 280,000 acres, and forced more than 44,000 residents to evacuate.The Carr Fire began on July 23 in Northern California, and on Saturday Fieri arrived in Redding, a city of almost 100,000 people where the fire swept through. Two days after Fieri got there, José Andrés' nonprofit, World Central Kitchen, joined him and fellow food first responders, Operation BBQ Relief."We hit the ground on Monday and started our meal operation today. Guy is heading to the Lake County Fire and we are taking over, and continue the efforts here in Redding," said Nate Mook, Executive Director for World Central Kitchen.With the help of Operation BBQ Relief, Fieri and his team were able to make over 1,000 meals twice a day, Mook said.BBQ Relief, whose main mission is to feed those affected by natural disasters in the United States, has around 30 volunteers and with World Central Kitchen's help it totals to 100 people on the ground to help feed those in need."We are planning to do 5,000 meals a day or more, depending on the need. We have the capacity and are prepared to cook 5,000 meals a day with no problem," Mook said.Fieri, alongside World Central Kitchen and BBQ Relief, are able to plan where help is needed the most by working with the Red Cross and the Salvation Army, who oversee the incident response.That way they can travel across the state to help everyone affected by the multiple wildfires."It's unbelievable to see what folks are going through, but it's even more unbelievable just how great this community is, and [to see] all these folks that have come together," Fieri said.Andrés is not in California, but he has been monitoring the situation and will fly in if needed."We got six chefs in Redding. Depending on the need we will bring more chefs and volunteers. We don't know what the next four days will look like, so he will be paying close attention," Mook said.Andrés recently left Guatemala, where he and his team were able to make more than 325,000 meals for those?affected by the volcano eruption last month.Mook said that even though the numbers can look a bit overwhelming, the volunteers get inspiration and passion to help those in need from all the support they receive from the communities."At the end of the day you just have to start somewhere, and just start cooking, cooking until everyone is fed," Mook said.As for Fieri, he takes pride in all the folks who drop everything just to help."We're in tough times ... with all of the things going on, you take a moment like this and you really see America is made of a lot of great people coming together," Fieri said. 3252

As one of the world's most famous prehistoric monuments, Stonehenge still holds many secrets despite centuries of study. For the first time, new research is lifting the veil on the people who are buried at Stonehenge.The study was published in the journal Scientific Reports on Thursday.Much of the previous research around the monument in Wiltshire, England, has centered around how or why Stonehenge was built -- not the people buried there or who built it.But studying the human remains at Stonehenge is no easy task. In addition to dating back to 3,000 BC, the remains were also cremated. During the early phase of Stonehenge's history, it largely served as a cemetery.Fortunately, lead study author Christophe Snoeck, post-doctoral researcher at the Vrije Universiteit Brussel, combined his passions for archeology and chemical engineering to pioneer developments in archaeological analysis.The results revealed that 40% of the people buried at Stonehenge likely came from west Wales, the suggested origin of the site's smaller bluestones, and they most likely helped transport the stones and build Stonehenge. Signals from the bone analysis suggested that within the last ten years of their lives, these people were not living at Stonehenge nor originally from the area around Stonehenge, known as the Wessex region."Our results are the first one to provide direct evidence on the origin of those buried at Stonehenge, shedding light on the importance of the site in the Neolithic landscape," Snoeck said in an email. 1531

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