ScienceShot: Honey, I Shrunk the Planet

Tag: 上海419论坛Ao

first_imgMeasuring just 4880 kilometers across, Mercury is a small world. The planet became slightly smaller as its interior cooled, which caused Mercury to shrink, buckling its surface and creating numerous cliffs and ridges. Now, after studying 5934 of these features, researchers report online today in Nature Geoscience that Mercury’s contraction was much greater than previously thought: During the past 4 billion years, the planet’s diameter decreased by 7 to 14 kilometers. Earlier estimates date back to data from Mariner 10, a spacecraft that flew past Mercury three times during the 1970s but saw less than half the planet. In 2011, however, the MESSENGER spacecraft began orbiting the sun’s innermost planet, imaging the entire surface. The greater estimate of shrinkage accords with models that predict how much a rocky planet should contract as its interior cools; the new work may also lend insight into the evolution of extrasolar planets that, like Mercury and unlike Earth, lack any moving continents.See more ScienceShots.Sign up for our daily newsletterGet more great content like this delivered right to you!Country *AfghanistanAland IslandsAlbaniaAlgeriaAndorraAngolaAnguillaAntarcticaAntigua and BarbudaArgentinaArmeniaArubaAustraliaAustriaAzerbaijanBahamasBahrainBangladeshBarbadosBelarusBelgiumBelizeBeninBermudaBhutanBolivia, Plurinational State ofBonaire, Sint Eustatius and SabaBosnia and HerzegovinaBotswanaBouvet IslandBrazilBritish Indian Ocean TerritoryBrunei DarussalamBulgariaBurkina FasoBurundiCambodiaCameroonCanadaCape VerdeCayman IslandsCentral African RepublicChadChileChinaChristmas IslandCocos (Keeling) IslandsColombiaComorosCongoCongo, The Democratic Republic of theCook IslandsCosta RicaCote D’IvoireCroatiaCubaCuraçaoCyprusCzech RepublicDenmarkDjiboutiDominicaDominican RepublicEcuadorEgyptEl SalvadorEquatorial GuineaEritreaEstoniaEthiopiaFalkland Islands (Malvinas)Faroe IslandsFijiFinlandFranceFrench GuianaFrench PolynesiaFrench Southern TerritoriesGabonGambiaGeorgiaGermanyGhanaGibraltarGreeceGreenlandGrenadaGuadeloupeGuatemalaGuernseyGuineaGuinea-BissauGuyanaHaitiHeard Island and Mcdonald IslandsHoly See (Vatican City State)HondurasHong KongHungaryIcelandIndiaIndonesiaIran, Islamic Republic ofIraqIrelandIsle of ManIsraelItalyJamaicaJapanJerseyJordanKazakhstanKenyaKiribatiKorea, Democratic People’s Republic ofKorea, Republic ofKuwaitKyrgyzstanLao People’s Democratic RepublicLatviaLebanonLesothoLiberiaLibyan Arab JamahiriyaLiechtensteinLithuaniaLuxembourgMacaoMacedonia, The Former Yugoslav Republic ofMadagascarMalawiMalaysiaMaldivesMaliMaltaMartiniqueMauritaniaMauritiusMayotteMexicoMoldova, Republic ofMonacoMongoliaMontenegroMontserratMoroccoMozambiqueMyanmarNamibiaNauruNepalNetherlandsNew CaledoniaNew ZealandNicaraguaNigerNigeriaNiueNorfolk IslandNorwayOmanPakistanPalestinianPanamaPapua New GuineaParaguayPeruPhilippinesPitcairnPolandPortugalQatarReunionRomaniaRussian FederationRWANDASaint Barthélemy Saint Helena, Ascension and Tristan da CunhaSaint Kitts and NevisSaint LuciaSaint Martin (French part)Saint Pierre and MiquelonSaint Vincent and the GrenadinesSamoaSan MarinoSao Tome and PrincipeSaudi ArabiaSenegalSerbiaSeychellesSierra LeoneSingaporeSint Maarten (Dutch part)SlovakiaSloveniaSolomon IslandsSomaliaSouth AfricaSouth Georgia and the South Sandwich IslandsSouth SudanSpainSri LankaSudanSurinameSvalbard and Jan MayenSwazilandSwedenSwitzerlandSyrian Arab RepublicTaiwanTajikistanTanzania, United Republic ofThailandTimor-LesteTogoTokelauTongaTrinidad and TobagoTunisiaTurkeyTurkmenistanTurks and Caicos IslandsTuvaluUgandaUkraineUnited Arab EmiratesUnited KingdomUnited StatesUruguayUzbekistanVanuatuVenezuela, Bolivarian Republic ofVietnamVirgin Islands, BritishWallis and FutunaWestern SaharaYemenZambiaZimbabweI also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events.Required fields are included by an asterisk(*)last_img read more


Tag: 上海419论坛Ao

first_imgThis week, a team from the National Institute on Drug Abuse (NIDA) reported that heavy marijuana use may damage the brain’s pleasure center. Meanwhile, researchers in the United Kingdom say they’ve figured out why pot makes you paranoid. But does focusing research on cannabis’s “bad side” give the drug short shrift? Science talked to Ian Mitchell, an emergency physician at the University of British Columbia’s Southern Medical Program in Kamloops, Canada, and author of the blog Clinical Cannabis in Context, who says that politics influences research in this controversial field. As a doctor who recommends medical cannabis to patients, he follows research on the drug and often critiques studies he believes are based on outdated information or were performed with an anticannabis bias.This interview has been edited for clarity and brevity.Q: What do you think of the NIDA study? Sign up for our daily newsletterGet more great content like this delivered right to you!Country *AfghanistanAland IslandsAlbaniaAlgeriaAndorraAngolaAnguillaAntarcticaAntigua and BarbudaArgentinaArmeniaArubaAustraliaAustriaAzerbaijanBahamasBahrainBangladeshBarbadosBelarusBelgiumBelizeBeninBermudaBhutanBolivia, Plurinational State ofBonaire, Sint Eustatius and SabaBosnia and HerzegovinaBotswanaBouvet IslandBrazilBritish Indian Ocean TerritoryBrunei DarussalamBulgariaBurkina FasoBurundiCambodiaCameroonCanadaCape VerdeCayman IslandsCentral African RepublicChadChileChinaChristmas IslandCocos (Keeling) IslandsColombiaComorosCongoCongo, The Democratic Republic of theCook IslandsCosta RicaCote D’IvoireCroatiaCubaCuraçaoCyprusCzech RepublicDenmarkDjiboutiDominicaDominican RepublicEcuadorEgyptEl SalvadorEquatorial GuineaEritreaEstoniaEthiopiaFalkland Islands (Malvinas)Faroe IslandsFijiFinlandFranceFrench GuianaFrench PolynesiaFrench Southern TerritoriesGabonGambiaGeorgiaGermanyGhanaGibraltarGreeceGreenlandGrenadaGuadeloupeGuatemalaGuernseyGuineaGuinea-BissauGuyanaHaitiHeard Island and Mcdonald IslandsHoly See (Vatican City State)HondurasHong KongHungaryIcelandIndiaIndonesiaIran, Islamic Republic ofIraqIrelandIsle of ManIsraelItalyJamaicaJapanJerseyJordanKazakhstanKenyaKiribatiKorea, Democratic People’s Republic ofKorea, Republic ofKuwaitKyrgyzstanLao People’s Democratic RepublicLatviaLebanonLesothoLiberiaLibyan Arab JamahiriyaLiechtensteinLithuaniaLuxembourgMacaoMacedonia, The Former Yugoslav Republic ofMadagascarMalawiMalaysiaMaldivesMaliMaltaMartiniqueMauritaniaMauritiusMayotteMexicoMoldova, Republic ofMonacoMongoliaMontenegroMontserratMoroccoMozambiqueMyanmarNamibiaNauruNepalNetherlandsNew CaledoniaNew ZealandNicaraguaNigerNigeriaNiueNorfolk IslandNorwayOmanPakistanPalestinianPanamaPapua New GuineaParaguayPeruPhilippinesPitcairnPolandPortugalQatarReunionRomaniaRussian FederationRWANDASaint Barthélemy Saint Helena, Ascension and Tristan da CunhaSaint Kitts and NevisSaint LuciaSaint Martin (French part)Saint Pierre and MiquelonSaint Vincent and the GrenadinesSamoaSan MarinoSao Tome and PrincipeSaudi ArabiaSenegalSerbiaSeychellesSierra LeoneSingaporeSint Maarten (Dutch part)SlovakiaSloveniaSolomon IslandsSomaliaSouth AfricaSouth Georgia and the South Sandwich IslandsSouth SudanSpainSri LankaSudanSurinameSvalbard and Jan MayenSwazilandSwedenSwitzerlandSyrian Arab RepublicTaiwanTajikistanTanzania, United Republic ofThailandTimor-LesteTogoTokelauTongaTrinidad and TobagoTunisiaTurkeyTurkmenistanTurks and Caicos IslandsTuvaluUgandaUkraineUnited Arab EmiratesUnited KingdomUnited StatesUruguayUzbekistanVanuatuVenezuela, Bolivarian Republic ofVietnamVirgin Islands, BritishWallis and FutunaWestern SaharaYemenZambiaZimbabweI also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events.Required fields are included by an asterisk(*)A: They said they gave marijuana abusers Ritalin and nothing happened. One of the ways you could interpret that is, OK, these pleasure centers are damaged. But you could also say, perhaps marijuana decreases the effects of [Ritalin] on people. That would be equally as right an interpretation.Q: Why do we hear more about studies that show negative effects of marijuana?A: NIDA is at the center of cannabis research in America. And their mandate, very plainly, is to study drug abuse. So they overwhelmingly fund studies that look at abuse. In America, if you wanted to run a study that showed a benefit of cannabis, you weren’t allowed to do that because NIDA couldn’t give you samples to use. So there were no trials [on potential medical benefits] being done. For example, there hasn’t been a good trial yet to study marijuana’s potential for treating posttraumatic stress disorder. They couldn’t get it done, due to all these political roadblocks.Q: How are changing laws—for example, legalization in Colorado, Washington, and Uruguay—influencing research on marijuana?A: Research on marijuana is flowering. States like Colorado are earmarking portions of revenue generated from marijuana sales for research. That’s going to be very helpful, because that money [unlike NIDA funding] will be free to be applied to looking for benefits. There’s certainly a lot more interest in it, and the political situation I think has improved significantly.I think it’s also very important to track social data about recreational use. Now, in Washington and Colorado, they’re tracking data on traffic accidents and fatalities, pedestrian accidents, suicide rates, homicide rates, that type of thing. That’s a tremendously important amount of data that has not really been tracked so far. Now that recreational use in those areas is legal, it’s much easier to study. In areas where it’s illegal, you can’t really ask people about those kinds of behaviors because they don’t want to get arrested.Q: Is there a danger that research on the medical benefits of marijuana will be politicized, too? Sometimes you’ll hear about anecdotal evidence of marijuana shrinking tumors, for example.A: Absolutely, and I think that’s a big concern. But that’s why the research needs to get done, because we have all these little stories of people saying, “I used this and my cancer got better.” And that’s nowhere near enough good evidence to start changing practice.There’s a lot of criticism leveled at cannabis research overall, and I expect it to continue. So the studies have to be good. They have to be of excellent quality, and they have to be scrutinized. And I’m sure they will be, very closely.last_img read more


Tag: 上海419论坛Ao

first_img Guest Writer 6 min read Image credit: FG Trade | Getty Images Founder and Principal, Triangle Investigations Next Article The only list that measures privately-held company performance across multiple dimensions—not just revenue. Apply Now » Even the less-enlightened workplaces of today have an understanding of the basics regarding no-nos in the workplace: Keep your hands to yourself at work. Discrimination, jokes and comments on a person’s race, sex, ethnicity or sexual identity are taboo. Related: Former Staffer Calls Out Facebook’s ‘Black People Problem’But within the last few months, a whole new world — a legally protected class, to be exact — has emerged within the workplace. And executives and organizational leaders need to rapidly and quickly educate themselves to navigate this new terrain with as few bumps as possible. I’m talking here about the rapidly developing topic of hair discrimination. Specifically, New York City and the State of California have recently taken up legislation or enacted policies making illegal any workplace discrimination based on hairstyles most typically sported by African Americans.Other jurisdictions may follow. So, are you ready? Are you knowledgeable about this subject, and is your workplace protected against claims of discrimination based on hairstyle? Here is a three-step process for learning more about this new topic and how to avoid the tripwires that could open your business to potential liability.Step 1: Understand the new laws.New York: In February 2019, the New York City Commission on Human Rights released new guidelines stating that any workplace policies that ban employees from wearing natural hairstyles — including cornrows, Afros and braids — are illegal and punishable by law. The New York City Commission on Human Rights specifically carved out this “protected class” status for black workers with natural hair — putting them in league with such protected classes as pregnant women and physically disabled persons.The new policy allows employees who have been harassed or discriminated against because of their hairstyle to take legal action against their employer; employers found to have violated the hairstyle guidelines face penalties of up to $250,000. According to the guidelines, examples of violations of the new policy would include:a workplace grooming policy that bans hair from extending a specified number of inches from the scalp (thereby limiting Afros and certain braided styles), andmanagement telling a black employee with natural hair that he or she cannot be in a customer-facing role unless the employee changes the disputed hairstyle.Related: 4 Tips to Help Workers From All Walks of Life Feel WelcomeWrote the New York Commision: “Treating an individual less well than others because of their actual or perceived race violates the New York City Human Rights Law…Black hairstyles are protected racial characteristics under the NYCHRL because they are an inherent part of Black identity.”California: On the heels of the creation of New York City’s new protected class, California began its own legislative process to outlaw discrimination based on hairstyle. The California law is cleverly named the “C.R.O.W.N.” Act, an acronym standing for: “Create a Respectful and Open Workplace for Natural Hair.”In late April 2019, California’s legislators, arguing for the new measure, took a deep dive into the history of the concept of “professional” hair, vociferously arguing that in America, looking “professional” had become a thinly veiled reference for Eurocentric ideas of what hair “should” look like: straightened, pinned and tightly affixed to the head. Both New York City and California, with their respective attempts to end such discrimination, have now turned on its head (no pun intended) the concept of what a professional work appearance is.Step 2: Learn the lessons of history, and watch your words.Few would argue that Jamaican singer-songwriter Bob Marley remains, 37 years after his death, one of the world’s most legendary, well-known and beloved musical icons. A brilliant lyricist, performer and counter-culture icon, Marley created music which, along with his personal appearance, became known worldwide.Image Credit: ullstein bild | Getty ImagesPop quiz: What’s the word you would use for Marley’s hairstyle? If you said, “dreadlocks,” you’d be wrong. And if you described someone’s hair as “dreadlocks” in the workplace, you could be opening yourself up to a potential lawsuit. There is a common agreement among historians that one of the first times the term “dreadlocks” was used was when white slave-catchers arrived in Africa. The term refers to the “dread” those men felt upon viewing the thick, natural hairstyles of the native Africans. Hence the term “dreadlocks,” which is essentially a way of saying, “disgusting and frightening hair.”It goes without saying that referring to an employee’s hair with a term whose history denotes such offensive connotations is unacceptable, and based on where you are located, may even be unlawful.Step 3: Ask for help if you need it.New workplace guidelines are being created in the wake of the #MeToo movement, as well as new rules of the road for employees using social media in the workplace and new classes of protected employees. Accordingly, employers may feel that their heads are spinning as they attempt to stay up to date on emerging issues and legislation.Related: They’re Doing It: Awe-Inspiring Black Female EntrepreneursBut a lack of policies and processes in a given workplace, based on managers not being up to date on emerging issues, will never serve as a defense in the instance of a discrimination lawsuit filed by an employee. So, if necessary, employers must absolutely seek third-party counsel regarding the new guidelines in their city or state, and learn how to educate their workforce about those guidelines.Once this education process is complete, employers must then create, via their own human resources department, or an independent workplace investigations group, a clear reporting process for employees registering concerns or complaints about sensitive issues in the workplace. Today’s trending topics related to race, sex, appearance, sexual identity and power show no signs of letting up, and it’s up to employers to protect themselves, their people and their bottom line. Discrimination May 15, 2019 Of Manbuns and Microbraids: ‘Hair Discrimination’ in the Workplace. What Business Owners Need to Know. –shares Kia Roberts Opinions expressed by Entrepreneur contributors are their own. New York City and California have now turned on its head (no pun intended) the concept of what a professional work appearance is. Add to Queue 2019 Entrepreneur 360 Listlast_img read more