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Intersection of 100th and 100th to be closed Tuesday morning

first_imgFORT ST. JOHN, B.C. – The City of Fort St. John is closing the intersection of 100th Avenue and 100th Street on Tuesday Morning.The area will be closed beginning at 6:00 a.m. so city workers can do routine repairs.The city is asking residents to find alternate routes to their destination and to obey all traffic control people.- Advertisement -There is no information on when the intersection will reopen. For the most up to date information visit the City of Fort St. John Facebook Page.last_img read more

Travel Agents See Increased Demand for Gadget-Free Vacations

first_imgTags:#Digital Lifestyle#web Top Reasons to Go With Managed WordPress Hosting Rosemary Dukelow was eight months into a solo, round-the-world trip when she boarded a cargo ship bound for Savannah, Georgia, in January 2011 – as the ship’s sole passenger. Up until that point, she had been a fixture at Internet cafes, constantly checking itineraries and updating the blog she kept to chronicle the trip.But once she boarded the Cap Cleveland in New Zealand, she found herself in a situation some of us dream of, and some of us dread: Dukelow was completely cut off from her online world for weeks at a stretch.“If you have to go somewhere remote because you’re addicted to technology, that’s one way to do it. But it’s missing the whole reason to travel.” – Sheri Wallace, editor of Road Trips for Families.“There is very little to do aboard a cargo ship besides watch the sunset and sunrise, read, and walk on deck. The crew is not in the business of entertaining the passengers, so the guests are left to find things to do on their own,” she said. “Until the time I boarded the cargo ship in New Zealand, it was very important to stay connected, to make plans for the next part of the trip, and to update my blog.”If the thought of a month with nothing but dead-tree books and dolphins makes your stomach tighten and your hand move to your pocket to make sure your smartphone is still safely in reach, you’re not alone. But travel agents say they’re seeing an uptick from people who are specifically looking for vacation destinations where they can – or will be forced to – break their electronic tethers.Getting There Is Half the EffortOn Sunday, the Boston Globe ran an article with the 10 best vacation destinations to unplug. The article highlighted out-of-the-way destinations or places that are specifically marketing to guests the chance to “recharge everything but their electronics.” And that may be the key to unplugged travel: It doesn’t just happen. You have to make plans and an effort to be gadget-free these days. And even when people plan a vacation specifically to unplug, many want contingencies for that “just-in-case” scenario. Alan Feldstein owns Infinite Safari Adventures and says access of some sort is important to a lot of his customers.“I always tell them that you can receive calls and emails on your phone out in the bush, but it is expensive and you will find that you are not really going to want to,” he said. They feel calm that they have that electronic lifeline, but then the most amazing thing happens. They find that once out on safari they didn’t really want to check their email on their phone, send texts and they do not need to be connected – the world continues to exist without them being ‘plugged in’ all the time.”Steve Davis of the San Francisco-based online travel agency CruiseWise said even traditional cruises can impose steep costs for passengers who want to be connected, but many take comfort in knowing they can make a ship-to-shore call in an emergency. He said the company has seen a steady increase in inquiries from customers about cell phone reception and Internet access over the past few years.“The limited internet and cell phone connectivity found on most cruise vacations is [often] seen as a plus. It’s an opportunity to truly disconnect,” Davis said. “One New York banker sighed audibly when I told him he wouldn’t be able to rely on constant internet access – he was thrilled to be totally unplugged for the first time in two years.”Try Gadget Brown Outs, Not Black OutsIf you’re not ready to completely unplug for a week, a long weekend, or even a Sunday morning, most experts recommend at least setting aside some time to be disconnected. Vacations can often be a good time to try a break from gadgets, because travelers are not in their usual routine and presumably have distractions to keep them offline.Sheri Wallace, editor of Road Trips for Families, said the types of road trips she takes with her husband and children by default force a lot of offline time. But she and her husband both work remotely, so cutting the tether completely is impossible.“We travel unplugged — sometimes for a month at a time or more,” she said. “We do catch up in the evening or early in the morning while the kids are sleeping, but the day is spent just roaming around with the family – back roads, hours without cell service.”Wallace suggests the key is to keep busy and make the trip to and from a destination part of the experience.“Whenever I do an interview about the topic, it’s like I said I starve the kids when I suggest that the DVD in the back seat is hurting more than helping. But… watching one movie after another just fosters the ‘are we there yet?’ mentality,” she said. “If you have to go somewhere remote because you’re addicted to technology, that’s one way to do it. But it’s missing the whole reason to travel.”Images courtesy of Shutterstock. dave copeland A Web Developer’s New Best Friend is the AI Wai…center_img 8 Best WordPress Hosting Solutions on the Market Why Tech Companies Need Simpler Terms of Servic… Related Posts last_img read more

Novel CRISPR-derived ‘base editors’ surgically alter DNA or RNA, offering new ways to fix mutations

first_img By Jon CohenOct. 25, 2017 , 1:00 PM Since the start of the CRISPR craze 5 years ago, scientists have raced to invent ever-more-versatile or efficient variations of this powerful tool, which vastly simplifies the editing of DNA. Two studies published in Science and Nature this week broaden CRISPR’s reach further still, honing a subtler approach to modifying genetic material that’s called base editing. One study extends a strategy for editing DNA, whereas the other breaks new ground by base editing its molecular cousin, RNA.Both open new avenues for genetic research and even curing diseases. “One shouldn’t view base editors as better than CRISPR—they’re just different,” says David Liu, a chemist at Harvard University who pioneered DNA base editing in a paper in Nature last year and co-authored the latest Nature paper. “It’s like, what’s better, a boat or a car?”CRISPR, adapted from a primitive bacterial immune system, does its handiwork by first cutting the double-stranded DNA at a target site in a genome. Base editing, in contrast, does not cut the double helix, but instead uses enzymes to precisely rearrange some of the atoms in one of the four bases that make up DNA or RNA, converting the base into a different one without altering the bases around it. That ability greatly increases the options for altering genetic material. “It’s a very worthwhile addition and it’s here to stay,” says CRISPR researcher Erik Sontheimer of the University of Massachusetts Medical School in Worcester.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(*)Many human diseases are caused by the mutation of a single base. CRISPR has difficulty correcting these so-called point mutations efficiently and cleanly, so base editing could provide a more effective approach. After Liu’s initial report, a group in China used DNA base editing to correct a disease-causing mutation in human embryos cloned from a patient with a genetic blood disorder.Conventional CRISPR uses a guide RNA (gRNA) coupled with an enzyme known as a nuclease, most commonly Cas9, that together attach to a specific stretch of DNA bases; the nuclease then snips the double helix. A cellular repair mechanism attempts to rejoin the cut DNA ends, but occasionally inserts or deletes bases, which turns the DNA code into gibberish and can knock out a targeted gene. “Gene editing based on nucleases is very good at inactivating genes,” says CRISPR researcher Feng Zhang of the Broad Institute in Cambridge, Massachusetts.Yet CRISPR, he notes, “is less efficient at making precise changes.” To fix a point mutation, a CRISPR-Cas9 system must also introduce a strand of “donor” DNA that has the correct base and then rely on a second cellular mechanism called homology-directed repair (HDR). But HDR works poorly unless cells are dividing, which means this strategy doesn’t function in, say, brain and muscle cells that no longer copy themselves. Even in dividing cells, the donor DNA rarely slots into the cut spot. Variations of the CRISPR DNA editor can change one DNA base into another. (GRAPHIC) C. BICKEL/SCIENCE; (DATA) D. B. T. COX ET AL., SCIENCE 358, 6362, 2017 © SCIENCE; J. DOUDNA AND E. CHARPENTIER, SCIENCE 346, 6213, 2014 © SCIENCE; GAUDELLI ET AL., NATURE 551, 7677, 2017 Shaury Nash/Flickr (CC BY SA 2.0) center_img Novel CRISPR-derived ‘base editors’ surgically alter DNA or RNA, offering new ways to fix mutations Base-editing systems, which borrow heavily from CRISPR’s tool kit, readily work in nondividing cells. DNA has four nucleotide bases—A, C, T, and G—and base editing changes one to another. In Liu’s 2016 study, his team fused gRNA with a “dead” Cas9 (dCas9) that cannot cut the whole double helix but still unzips it at the correct spot. To this complex the researchers tethered an enzyme, APOBEC1, which triggers a series of chemical reactions that ultimately change C to T. DNA’s base-pairing rules, which specify that a T on one DNA strand pairs with an A on the opposite strand, govern a subsequent change. The dCas9 was further modified to nick the unedited strand, which gooses the cell’s DNA repair mechanism into converting the G that originally paired with C into an A that pairs with the new T.That first DNA base editor could not address the most common point mutations associated with human diseases—accounting for about half—which have A•T where there should be G•C. The new editor from Liu’s group can now make this fix. The team again fused gRNA with a dCas9, but there is no known enzyme that can convert A to G in DNA. So the lab developed one from TadA, an enzyme in the bacterium Escherichia coli. The new enzyme converts A to a base called inosine, or I. Either a cellular repair mechanism or the process of the DNA copying itself then changes the I to a G. “The big deal here is engineering the TadA enzyme to do something fairly unnatural,” says George Church of Harvard, who studies CRISPR. “My hat is off to them.”Zhang’s team created its RNA base-editor system by fusing gRNA with a different dead nuclease, dCas13, and a natural enzyme that converts A to I in RNA. Unlike in DNA, that’s where the changes stop. The I-containing RNA simply performs as if it had a G in that spot.Because RNA carries the genetic message from DNA to the cell’s proteinmaking factories, or can directly perform acts such as gene regulation, it, too, is an appealing target for therapies. But an RNA only sticks around in a cell for a short time. That means RNA base editors likely would have to be repeatedly administered to work as a therapeutic, which Zhang and his co-authors suggest may make sense for transient conditions, such as localized inflammation.Although the short-lived nature of RNA makes base editing less attractive for many therapies, Sontheimer sees an upside, too. “In some ways, it’s safer to work on RNA,” he says. Researchers worry that genome editing could accidentally affect the wrong part of the genome—a change that would be permanent with a DNA base editor. “If there’s some degree of off targeting, you’re not permanently etching those mistakes into the underlying genome” with an RNA base editor, Sontheimer says.Church says base editing should be evaluated “case-by-case” for whether it offers advantages over CRISPR and other technologies that alter nucleic acids. “People make it sound like [changing bases] was not possible before. In fact it was hard or just inefficient,” he notes.Zhang and Liu stress that it could be several years before base-editing therapies enter clinical trials—and longer until it’s clear whether the strategy offers advantages over existing gene therapies. “It’s both scientifically short-sighted and long-term incorrect to conclude that base editing is going to be a better way to do human genetic therapy,” Liu says. What’s already clear, however, is that powerful alternatives to standard CRISPR are now in the game. Getting to the point of mutations Base editors borrow from CRISPR’s components—guide RNAs (gRNAs) and Cas9 or other nucleases—but don’t cut the double helix and instead chemically alter single bases with deaminase enzymes such as TadA and ADAR.last_img read more