濮阳东方妇科专业(濮阳东方妇科咨询医生) (今日更新中)

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

About 20,000 residents are under mandatory evacuation orders as a Southern California fire -- which authorities say was set intentionally -- spread this week.The Holy Fire started Monday in the Cleveland National Forest and has so far destroyed 12 structures, according to fire authorities.A man has been arrested in connection with the fire that is wreaking havoc near the border between Orange and Riverside counties, which are among the most populous counties in California.The Holy Fire has burned 6,200 acres and is 5% contained.Although it's not the largest fire burning in the state, there are growing concerns about how it could affect residential communities -- including Lake Elsinore. Some small communities in Riverside County are under mandatory evacuation orders affecting about 7,000 residential structures, according to authorities.Forrest Gordon Clark, 51, was being held at the Orange County Jail on Wednesday on suspicion of two counts of felony arson, a count of felony threat to terrorize and misdemeanor resisting arrest, the Cleveland National Forest said via Twitter.He is being held on million bail and expected in court on Thursday.The charges being leveled could carry a life sentence, said Susan Schroeder of the Orange County District Attorney's Office."Arson is a terrible crime that destroys dreams," she said in a press conference Wednesday.Witness statements, physical evidence and fire burn patterns connected the man to the fire, said Shane Sherwood with the Orange County Fire Authority.Volunteer Fire Chief Mike Milligan told the Orange County Register that Clark was screaming in the community and sent an email that said "this place will burn" last week.Before he was arrested, Clark told a cameraman he was asleep when the fire started and had no idea how it began."Who would go out with low humidity, and high wind and highest heat temperatures this time of year and intentionally set the forest on fire?" asked Orange County Supervisor Todd Spitzer during Wednesday's press conference.An excessive heat warning for the fire area has been issued with temperatures higher than 100 degrees."We know this district burns, but it should never burn because of an intentional act," Spitzer said. "This shouldn't be called the Holy Jim Fire, this should be called the Holy Hell Fire."Spitzer added that his constituents are "scared" and "fleeing their homes.""They're leaving property behind, they're putting everything they can in the back of their cars as quickly as possible."Fire officials warned residents to heed evacuation orders."Even if you're miles way, you want to be prepared if you're near the fire area or in an environment that can burn," said Thanh Nguyen with the SoCal Team One Fire Management Team, who suggested having a packed bag ready to go.  2814

According to court documents, the members of a militia group who allegedly plotted to kidnap and kill Michigan Gov. Gretchen Whitmer hoped to conduct executions of politicians on live TV.The documents state that Adam Fox — the man who state and federal officials have called the alleged "ringleader" of the Wolverine Watchmen militia group — devised two separate plans. "Plan A" included recruiting 200 men, taking over the entire state Capitol building, taking hostages and executing "tyrants" on live television.A secondary plan was to lock the door and set the building on fire.Fourteen men have been charged by the state and federal government in related cases. The documents were filed in Jackson County Court last month.The plot planning went on for about six months. Whitmer was allegedly targeted because she imposed the shutdowns of non-essential businesses amid the COVID-19 pandemic; the plot was supposed to be carried out before the November election.Federal and state authorities have said much more evidence will be coming out as the cases against the 14 charged move forward in court.Federal officials have asked a judge in Grand Rapids, who has jurisdiction over six of the men charged, for a protective order to keep the names of confidential informants and undercover FBI agents private.This story was originally published by WXYZ in Detroit. 1369

A woman who attacked a bus driver after she missed her stop was partially responsible for a dramatic crash in southwestern China which killed all 15 people on board, an investigation by Chinese authorities revealed Friday.A 10-second clip from the on-board camera released by Chongqing police showed a female passenger yelling at the male driver while he was steering, shortly after 10 a.m. on Sunday.The 48-year-old woman then attacked the driver with her cell phone, while he fought back with his right arm.When she struck him again, he abruptly turned the steering wheel left, swerving into oncoming traffic before crashing into the railings on the side of a bridge -- screaming can be heard as the video stops.The release of the clip brings an end to the mystery surrounding the cause of the deadly crash, which has come to captivate China amid extensive television coverage of a massive search-and-recovery effort. 927

According to President Donald Trump, the tragic Texas church shooting that left 26 people dead was "a mental health problem at the highest level."If you ask mental health researchers, such mass shootings are much more complicated than that.On Sunday, 26-year-old Devin Kelley sprayed bullets across the sanctuary of First Baptist Church in Sutherland Springs, Texas, about 30 miles east of San Antonio. The youngest killed at the church was 17 months old; the oldest was 77 years old."We have a lot of mental health problems in our country, as do other countries, but this isn't a guns situation," Trump said during a joint news conference Monday in Tokyo."This is a mental health problem at the highest level," he said. "It's a very, very sad event."Trump's response to the Texas church shooting echoed previous comments he has made on gun violence. In 2015, Trump said he was opposed to tightening gun laws in the United States but was in favor of addressing mental health to prevent shootings.Yet various epidemiological studies over the past two decades show that the vast majority of people with severe mental illnesses, such as schizophrenia, bipolar disorder or severe depression, are no more likely to be violent than anyone else.Rather, people with severe mental illnesses are more than 10 times more likely to be victims of violent crime than the general population. And, only about 3% to 5% of violent acts can be attributed to individuals living with a serious mental illness, according to the US Department of Health and Human Services.But those statistics have "almost nothing to do with mass casualty shootings," said Jeffrey Swanson, a professor in psychiatry and behavioral sciences at Duke University who specializes in gun violence and mental illness.So exactly how are mental health and gun violence intertwined, and what is needed to end the violence?Gun violence and mental illness are public health problems "that intersect at the edges" but have very little overlap, Swanson told CNN last year.There's no doubt that America's systems of care for mental health are overburdened, expensive and inaccessible for many who need them, he said. But when it comes to gun violence among this community, suicide tends to occur at higher rates than homicides, he said."If we back up and think about firearm-related injuries and mortality as a public health problem, it turns out there is a mental health-related story, and it's suicide," he said. "If we had better mental health care and could get people better access and break down barriers to care, then yes, we might reduce gun violence by a lot but it would be from reducing suicides."Otherwise, mental illness is just one "highly unspecific" factor that may contribute to gun violence, along with being young, white and male, or a history of violence, Swanson said.Instead of policies that restrict gun access based solely on mental illness diagnoses or because a person has made contact with the judicial system or health care agencies due to mental illness, the American Psychological Association, the National Alliance on Mental Illness and other advocacy groups have called for gun access criteria based on more subtle indicators of potentially dangerous behavior.Those indicators -- such as having past or pending violent misdemeanor convictions or charges, domestic violence restraining orders or multiple DUI convictions -- have been largely informed by the work of Swanson and others.Swanson supports intervention at the point of purchase through comprehensive background checks -- but to make background checks work, criteria for inclusion on the database should be based on other indicators of risk besides mental health history, such as those indicators of aggressive, impulsive or risky behavior."A history of violent behavior is a far better predictor of future violence than mental illness," he said.Calling gun violence a mental health issue is to scapegoat and stigmatize people with mental illness, he said."It's kind of a canard, a convenient explanation that exploits the tremendous fear people have with these horrifying mass shootings," he said. "If people fear those with mental illness they're going to treat them with scorn and support public policies that restrict their liberties."After all, mental illness affects millions of adults across the country.In 2015, there were an estimated 43.4 million adults in the United States with some form of mental illness within the past year, which represented 17.9% of adults nationwide, according to the National Institute of Mental Health.The American Psychological Association recommends prohibiting firearms for high-risk groups, such as domestic violence offenders or persons convicted of violent misdemeanor crimes."Reducing the incidence of gun violence will require interventions through multiple systems, including legal, public health, public safety, community, and health. Increasing the availability of data and funding will help inform and evaluate policies designed to reduce gun violence," according to the association's website.Swanson and his colleagues examined the proportion of people in the United States with impulsive angry behavior who own or carry guns and have a diagnosable mental illness in a paper published in the journal Behavioral Sciences & the Law in 2015.They conducted household surveys with 9,282 people from February 2001 to April 2003, excluding people who carried guns for work, resulting in a response rate of 70.9%.An analysis of the survey results estimated that nearly one in 10 adults has access to firearms and has a problem with anger and impulsive aggressive behavior.These people were more likely to be male, younger and married and to live in outlying areas around metropolitan centers rather than in central cities, Swanson and his colleagues wrote in their paper.They were significantly more likely to meet diagnostic criteria for a wide range of mental disorders, including depression, bipolar and anxiety disorders, PTSD, intermittent explosive disorder, pathological gambling, eating disorder, alcohol and illicit drug use disorders, and a range of personality disorders.What's more, despite evidence of "considerable psychopathology" in many of these respondents, only a very small proportion, 8% to 10%, were ever hospitalized for a mental health problem."Because only a small proportion of persons with this risky combination have ever been involuntarily hospitalized for a mental health problem, most will not be subject to existing mental health-related legal restrictions on firearms resulting from a history of involuntary commitment," Swanson and his colleagues wrote in the paper's abstract.As for Texas gunman Kelley, the state denied him a license to carry a gun, Gov. Greg Abbott said, citing the director of Texas' Department of Public Safety."So how was it that he was able to get a gun? By all the facts that we seem to know, he was not supposed to have access to a gun," Abbott told CNN's Chris Cuomo. "So how did this happen?"On Monday, Trump said his "thoughts and prayers" were with the victims and their families but did not suggest plans to take any legislative or other policy action to address the shooting. 7228

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