济南硬不起来怎么回事(济南前列腺炎要做那些检查) (今日更新中)

Absolutely unnecessary. Call Rusty Bowers in AZ and tell him not to use COVID as an EXCUSE!! https://t.co/tWoXAVeWFa— Jenna Ellis (@JennaEllisEsq) December 7, 2020 171

According to a recent paper, the Earth is caught directly in the crosshairs of a cosmic hurricane.A swarm of nearly 100 stars, accompanied by an even greater amount of dark matter, is aimed directly at our stellar neighborhood and there's nothing we can do to stop it; in fact, the vanguard is already upon us. This sounds like a perfect summer blockbuster movie, starring The Rock and Chris Pratt, or maybe Scarlett Johansson and Charlize Theron.Except this is for real. But is it a danger? Well, actually, no. Not at all. But it's potentially incredibly fascinating, with lots of interesting scientific interconnections. So, what is really going on?The story starts last April, when the Gaia satellite announced the locations and trajectories of 2 billion stars in the vicinity of the Milky Way surrounding our sun. They released the data to the public.Scientists were then able to look at the data set to see if they could spot anything peculiar. In galaxies like the Milky Way, the most common behavior is that the stars orbit the center of the galaxy in a manner broadly similar to the planets orbiting our sun. However, there are some stars that exhibit unusual motion. About a year ago, astronomers identified some "stellar streams" passing through our celestial neighborhood.One of them, called S1 (for stream 1), consists of nearly 100 stars of similar age and composition, orbiting the Milky Way in a direction exactly opposite that of normal stars. It's kind of like a handful of cars driving the wrong way down the highway, except with a much greater distance between them and with no likelihood of a collision. These stars are spread out over a few thousand light years and they will pass through the solar system's neighborhood over the course of a few million years.Astronomers identified S1 as being part of the remnants of a dwarf galaxy that collided with the Milky Way and was consumed in an epic episode of cosmic cannibalism. Dwarf galaxies are very small, typically about 1% the mass of the Milky Way. They can orbit larger galaxies and collide with the bigger galaxy, adding their mass to the parent. This is what appears to have happened in the case of S1, although the process has taken probably a billion years.Dwarf galaxies often have a disproportionately large fraction of dark matter. Dark matter is a hypothetical and still-undiscovered form of matter that interacts only gravitationally. Scientists have proposed its existence to explain many astronomical mysteries, for example the observation that most galaxies rotate faster than can be explained by the known laws of physics and the stars and gas of which they are composed.While dark matter has not yet been observed, hypothesizing its existence is the simplest and most economical explanation for myriad astronomical mysteries. Averaged over the entire universe, dark matter is thought to be five times more prevalent than the ordinary mass of stars and gas and planets.In dwarf galaxies, the fraction of dark matter is often higher. In Fornax, a well-studied dwarf galaxy orbiting the Milky Way, researchers estimate that the dark matter is between 10 and 100 times greater than the mass found in its stars.If that number holds for S1, the dark matter of the S1 stream is passing through the Earth at a much higher velocity than the more ordinary dark matter that orbits the Milky Way -- about twice as fast. It is thought that S1 dark matter is flying through the solar system at a speed of about 550 km/s, or about 1.2 million mph. While these numbers are impressive, they are misleading. Dark matter, if it exists, is extremely diffuse and it will have no discernible effect on the solar system.Because dark matter hasn't been observed yet, these velocity numbers are speculative, although they are strongly supported by a very large body of evidence. However, the prospect of high velocity dark matter flying through the Earth has suggested an opportunity to detect it.In a paper in the prestigious journal Physical Review D, researcher Ciaran O'Hare and his collaborators calculated the possibilities of discovering dark matter using both existing and proposed dark matter detectors. They considered two varieties of dark matter particles: a very heavy kind called a WIMP (weakly interacting massive particle) and a very light kind called an axion. Because the ultimate nature of dark matter is not known, it is important to be open to all possibilities.They found that the detectors they evaluated could find WIMPs for certain ranges of the particle mass. However, when they looked at the axion possibility, it appeared the prospects were even better. Because of its light mass and the manner in which an axion would interact with the detector, the apparatus simply has a better chance of seeing the axion. (If axions exist, of course.)Experiments with names like ADMX, MADMAX and ABRACADABRA are able or will be able to search for the signatures of dark matter proposed in the recent paper. They consist of technologies that are designed to interact with axions in a strong magnetic field and convert them to ordinary microwaves or radio waves that can be easily detected.It's important to remember that the S1 stream poses no credible threat to the Earth and humanity. There is no need for an action hero to save us. However, the synergy of science is staggering. A careful catalog of nearby stars has opened the prospect of a better possibility of finding and identifying dark matter, which is one of the great unanswered mysteries of modern physics. It's an amazing time we live in, in which we can study such things.\ 5625

Alyson McClaran is a photojournalist who has captured many of the raw moments and emotions in 2020, including a photo of nurses blocking protestors in Colorado earlier this year.“The nurse kind of put his hands out,” McClaran said. “Then, the gentleman got in his face and the nurse just looked away from him and ignored him.”That photo would end up gaining international attention. “Within 30 minutes, I had thousands of shares,” she said. And for good reason.“I remember when I first saw it, it was really striking,” Hahrie Han, professor of political science at Johns Hopkins University, said. “It sort of felt like it brought together a lot of the complex streams of conflict and tension that we were having to grapple with as a society.”Han was chosen as a curator for a COVID-19 time capsule created by the non-profit Social Science Research Council, or SSRC. She chose McClaran’s photo.“The act of both people in that picture was an act of trying to make change in some way,” she said. “The people in the cars who are protesting are protesting against the shutdown order and they're using their right to free assembly and free speech to voice their concern. And likewise, the healthcare worker is standing up against that saying, 'No, we want people to stay home because that's how you’re going to protect us. That's how we are going to protect each other.'”As we close out this dynamic year, the SSRC decided to create this time capsule, not only for future social researchers but for the general public, as a reflection on 2020.The content ranges from ironic toilet paper shortage-related memes to images of hope and human connection.“They were like instant artifacts of that moment and there were a lot of those moments,” Alexa Dietrich, program director at the Social Science Research Council, said. “I believe it has accomplished a set of goals in the sense that bringing this type of analysis and perspective to much broader audiences.”Dietrich said the capsule is meant to bring about ongoing reflection, just as these curators had to do when coming up with their selections to put in the project.“That image I chose is the sort of 'how would you like to pay?' sign you'd see at any retail store or restaurant. But instead of having just the Visa, Mastercard, or Amex, it also has a roll of toilet paper,” said Bill Maurer, professor of anthropology and law at UC Irvine and another curator for the time capsule. “It really spoke to things like the concerns over hoarding that were taking place early on the pandemic, particularly around toilet paper. But, then, also that broader philosophical question, when you're in a global pandemic and there is an economic shutdown, what really is valuable anymore?”The time capsule is part of a bigger project the SSRC is putting together, free of use, to offer a range of perspectives and thoughts on the past year. “We’re not just delivering, we’re also really trying to learn and promote conversations,” Dietrich said.“The world is just in this moment of dynamism and flux and so to take this snapshot this moment in time, to think about what we want to capture and to create a historical record for future generations, I think is really important,” Han said. 3225

A Wisconsin judge has ruled against a Trump campaign lawsuit that sought to overturn the results of the presidential election in the state.“Because the court is satisfied the rules and guidelines applied in each of the disputed areas are reasonable, and a correct interpretation of the underlying early absentee voting laws, the certification of the results of the 2020 Wisconsin presidential election, after the Dane County and Milwaukee County recounts, is affirmed," Judge Stephen Simane said in a ruling released Friday.Hearings were scheduled Thursday for the campaign's federal and state lawsuits that were an effort to invalidate thousands of ballots in both Dane County and Milwaukee County.The attempt to overturn ballots in Milwaukee County was dismissed Thursday afternoon.Prior to the decision, attorneys for Wisconsin Gov. Tony Evers and the state elections commission said the cases are without merit and should be dismissed.The ruling clears the way for Wisconsin's 10 electoral college votes to go to Biden. The body will formally vote on Monday to seal Biden's win.This story is breaking and will be updated. 1133

A ?????????????? delivery for #Big12FB fans??Your first look at the 2?0?2?0? Conference schedule ?? pic.twitter.com/1W00A3EYuM— Big 12 Conference (@Big12Conference) August 12, 2020 188

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