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Yosemite Valley loses its last no-reservation campground, climbers’ famous Camp 4

first_imgCamp 4’s iconic centerpiece is Columbia Boulder. The lightning bolt — originally drawn by legendary climber John Bachar — marks the boulder problem called Midnight Lightning.Yosemite’s freewheeling Camp 4, famous as the incubator for the valley’s rock climbing scene, is no longer first-come, first-served.Under a pilot program, a daily lottery system will assign campsites there from May 22 until early September. After that, the system will revert to the no-reservation system until the …last_img

Cellular Cowboys: How the Cell Rounds Up Chromosomes Before Dividing

first_imgTwo cancer researchers from UC San Diego describe mitosis (cell division) in the Mar. 4 issue of Nature.1  Pulling together the latest findings about this elaborate and important process, they begin by describing the puzzle that the cell needs to solve:At the beginning of mitosis, the process of cell division, chromosomes are organized randomly – like jigsaw puzzle pieces spread out on the floor.  Their constituent two ‘sister chromatids’, each of which contains one of the two identical DNA molecules produced by replication, must be oriented such that they will be pulled in opposite directions into the two newly forming cells.  Like a jigsaw, the solution for correctly orienting all chromosomes comes partly through trial and error.  Mechanisms must exist to eliminate wrong configurations while selecting the right ones.In the article, they describe how cables (microtubules) connect to handles (kinetochores) on the chromosomes and start pulling them in opposite directions.  Another enzyme dissolves the molecular “glue” in the centrosomes that hold the sister chromatids together, so that the opposite poles of the spindle can pull them apart into the daughter cells.    A newly-described “highly-conserved enzyme” (i.e., identical in yeast and vertebrates), named Aurora B kinase, somehow finds chromosomes that lack an attachment to the other pole of the spindle, and fixes them.  Apparently this enzyme is able to identify chromosomes that are incorrectly lassoed to the same pole (syntelic attachment) and therefore are not under tension.  Only when there is tension on each chromosome, pulling the sister chromatids toward opposite poles, will the process continue.  “Finding out how Aurora B identifies and corrects them is an obvious next step,” the authors say.Ian M. Cheeseman and Arshad Desai, “Cell division: Feeling tense enough?”, Nature 428, 32 – 33 (04 March 2004); doi:10.1038/428032b.First of all, think of how many parts are involved in this process.  Then realize that without high fidelity duplication and segregation during cell division, an organism would be subject to cancer, genetic disease or death.  Furthermore, any alleged evolution would quickly come to a grinding halt, because natural selection is highly dependent on accurate replication for selected traits to be preserved.    To visualize what goes on in mitosis, think of the following analogy.  (Analogies, though never precise, and inadequate as proofs, can help make complex processes approachable.)  Let’s head out West and picture a team of cowboys who need to split a herd of cattle for market.  The cattle in our hypothetical herd all have identical twins that are yoked together.  They are wandering aimlessly in a corral, and two teams of cowboys are standing at opposite ends of the corral with lassos in hand.  On cue, the corral fence (the nuclear membrane) drops.  The cowboys immediately go into action, lassoing every cow in sight.    Their goal is to split the herd into identical halves.  To accomplish this, each team has to catch one of each pair: Bob, on the north team, lassos one of the twins, and Joe, on the south team, lassos the other.  As soon as a cow is caught, the cowboy starts pulling.  Sometimes, however, two guys on the same team catch both twins.  That’s when wrangler Chuck (Aurora B kinase) rides through the herd, looking at ropes that aren’t taut, indicating pairs hitched to the same team.  Chuck removes one of the ropes and lets the other team lasso the twin.  As the ropers keep applying tension, the boss makes sure all the pairs are lined up, each with one rope pulling a cow north and another rope pulling its twin south.  Then another wrangler breaks the yokes, and the cowboys wind in their ropes, pulling their half of the herd into the new north and south corrals.    The difference in cells is that they don’t have sentient cowboys with eyes and ears doing the work by using their brains and roping skills.  Instead, cables called microtubules extend outward blindly at random from the spindle poles, looking for attachment points on the kinetochores at the middle of the chromosomes.  Tension is applied by molecular motors (see 02/25/2003 headline), like winches, that pull the chromatids into the daughter cells.  How can a cell make sure one and only one cable gets attached to each chromatid?  This is awesome.  Consider also that all the machinery, all the ropes, all the winches, all the corrals, all the procedures and everything else is produced by the DNA in the chromosomes, as if the cattle were the master controller and supplier for the cowboys!  For photomicrographs of mitosis, see the illustrations at the Florida State University and the University of Maryland websites.    Mitosis is a coordinated team project that is done exactly right by the cell every time it divides.  Mistakes by cowboys might mean a lawsuit or the loss of business, but in the cell, a mistake can mean death.  The process is amazing enough as described, but then the authors throw in “the rest of the story” to boggle Darwinian minds beyond all hope of recovery.  What they described was for yeast – a “primitive” form of life.  What happens in vertebrates, like us humans?  Get ready:In contrast to budding yeast, kinetochores of other eukaryotes bind multiple microtubules (about 20 in humans).  These larger kinetochores must coordinate all these microtubules and also deal with incorrect attachments in which microtubules from opposite spindle poles connect to a single kinetochore (termed ‘merotely’).  Another study, in this month’s Nature Cell Biology, found that Aurora B does not merely detach syntelic kinetochores from microtubules in vertebrates – it orchestrates the coordinated disassembly of all the microtubules that are bound to each kinetochore, so that the syntelically oriented chromosomes move towards the spindle poles before they are bi-oriented.    Although sister kinetochore geometry seems to be dispensable in budding yeasts with their single-microtubule-connected kinetochores, it could contribute to reducing merotely, as implied by the conservation of this aspect of chromosome architecture throughout eukaryotic evolution.  Tackling the extra dimension that the multiplicity of microtubule-binding sites at kinetochores introduces will undoubtedly be another brain-teaser – and a particularly important one, too, because the loss of a single chromosome can be lethal, and aberrant numbers of chromosomes can contribute to birth defects and cancer.Isn’t evolution wonderful.  It blindly found a way to solve multi-dimensional jigsaw puzzles correctly every time, and hung onto its invention for millions of years.  It started a successful cattle ranching business, employing blind cowboys.  Its advertisement boasts, “Satisfying customers since 2 billion years B.C.”  Would you trust such hype?    One last thought.  Remember the 02/13/2003 headline last year?  It reported that meiosis (cell division for sexual reproduction) is even “much more complex” than mitosis, but there was no evidence it had evolved from the “simpler” process of mitosis.  These are bad days to work for Charlie on the Lazy E Ranch.  Better quit the outfit while you can and join up with the Boss who knows the business.(Visited 9 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

Story of Madiba and Zelda set for the big screen

first_img25 February 2016Zelda la Grange’s ‘Good Morning Mr Mandela’ to become a movie https://t.co/r0POLX37k5 pic.twitter.com/6ekvz5oN3S— Times LIVE (@TimesLIVE) February 23, 2016Zelda la Grange published her memoir, Good Morning, Mr Mandela, in 2014 to wide acclaim. Since then, it has been published worldwide, in several languages; now it is set to become a film.The book covers her years as private secretary to Nelson Mandela during his presidency and in his post-presidential staff until his death in 2013. La Grange was also a founding staff member of the Nelson Mandela Foundation.While many books have been written about the life of Mandela, La Grange’s was the first to offer an inside look at the day-to-day dealings of the person behind the icon. It offers a rare portrait of a humble but proud man on the pinnacle of history.The book also explores the contrast of a young, white Afrikaans woman serving the first black president of a newly democratic South Africa. It acts as a metaphor for the country as a whole, dealing with rapid changes and learning new ways to reconcile its turbulent history with its transition to democracy.In the book, La Grange also pays tribute to a man who taught her valuable lessons about human relationships and forgiveness.Bill Clinton, the former American president, called La Grange’s book “an important reminder of the lessons Madiba taught us all”.That remarkable story is now set to become a film, as announced on 22 February.Renowned, award-winning producer Trudie Styler, the producer of cult hit Lock, Stock and Two Smoking Barrels and the Bafta-winning science fiction film Moon, and her Maven Pictures have bought the rights to the book and have already begun working on a script.Let’s make a movie! @ZeldalaGrangeSA #GoodMorningMrMandela https://t.co/FYGdKdET4E— Maven Pictures (@Maven_Pictures) February 22, 2016La Grange relayed the news via Twitter this week, enthusiastic about telling one of South Africa’s good stories.Thank you Maven Pictures for believing in the power of a South African story https://t.co/9QBWbx3lXD— Zelda la Grange (@ZeldalaGrangeSA) February 22, 2016As news of the proposed film spread this week, naturally the Twitterverse was rife with speculation about who should play Zelda in the film, with most suggesting that South African-born Oscar winner Charlize Theron would be the natural choice. Other suggestions included Julianne Moore, Naomi Watts and Game of Thrones’ Emilia Clarke.More importantly, who should play Madiba this time around? With Oscar nominated performances by Idris Elba in Mandela: The Long Walk to Freedom in 2013, and Morgan Freeman in Invictus, among other portrayals, it seems the field might be limited as far as international actors are concerned.Perhaps this time, as has been a popular sentiment among South Africans, a local actor should get the role: John Kani, Sello Maake ka Ncube or World War Z’s Fana Mokoena, maybe?Whoever may be cast, the film, no doubt, will be an opportunity to tell the world another great South African story.Source: News24Wirelast_img read more

Make Your Project Stand Out With 3D Titles in Final Cut Pro X

first_imgCreating 3D Titles in Final Cut Pro XStep 1: Drag the Text to Your TimelineTo get started, drag the Tumble 3D text effect into your timeline. You’ll find this effect under the Titles tab — it’s the one with the large “T” icon. When you drag the file into your timeline, you’ll be prompted to name the resolution and frame rate of your timeline. Choose whatever is appropriate for your project. In our example, we’re using 1080p HD at 23.98 frames per second.Step 2: Stylize the TextWith your text selected in the timeline, navigate to the Text tab in the Inspector window at the top right of the Final Cut Pro window. From this tab you can adjust all the various parameters that are going to make your text awesome. Pick a font that looks great on screen.For our example we’ll use the font called Marion. Perform the following steps to make your titles look exactly like our example:Increase the DepthRound the Depth to 40Change the Bevel Edge type to RoundIncrease the Edge Size to 3.3Change the Lighting Style to Diagonal RightTurn the Lighting Intensity Down to 20%Change the Custom Environment Map to ‘Soft Box Above’Increase the Intensity of the Lighting to 190%Change Your Material to Metal>Brushed CircularSelect Multiple from the Materials MenuChange the Side Material to Metal>Old SteelStep 3: Keyframe a DriftUnder the Video tab, add a scale keyframe by hitting the plus icon on the first frame. Move forward about five seconds and scale down the footage to create a drifting effect.Step 4: Add the BackgroundNow it’s time to add your background. You can do this by simply dragging your background video element down from your Clips panel.Step 5: Add the Flare ElementDrag your flare element into your composition. In our example, we had our flare over the text for a few frames, then below for the remainder of its duration. Change the Blending Mode to Add.Step 6: Apply Some Quick Color CorrectionTo make your text blend better with your background, apply the Color Correction effect to your text and change the levels as needed.This is, of course, one of the many ways to stylize 3D titles in Final Cut Pro X. For additional Final Cut Pro tutorials, check out our Final Cut Pro X page here on PremiumBeat.What’s your favorite way to create 3D text in Final Cut Pro? Share your advice in the comments below. Learn the trick to creating monumental 3D titles in Final Cut Pro X. Master the technique with FREE stock footage and music from Shutterstock and PremiumBeat.Thanks to an amazing set of textures and presets, it’s a breeze to create 3D titles in Final Cut Pro X. Using various video tools, users can create a wide assortment of 3D text without needing to first master a complex 3D application. Let’s look at how to create 3D titles in Final Cut Pro. This video tutorial will show you exactly how to make your 3D text stand out.But don’t just watch the clip… fire up Final Cut Pro X and make your own eye-catching 3D text! We’ve teamed up with Shutterstock to give you free assets so you can follow along.You can download the free footage, sound effects, and assets from the Final Cut Pro X page here on PremiumBeat.Download Free 3D Title Assetslast_img read more

India win third Test against NZ, clinch series

first_imgIndia beat New Zealand by an innings and 198 runs in the series-deciding third Test on Tuesday and clinched the Test series. The first two Tests, in Ahmedabad and Hyderabad, were draws.SCORECARDPacer Ishant Sharma and spinner Harbhajan Singh took three wickets apiece. All-rounder Suresh Raina and spinner Pragyan Ojha also contributed with key scalps in the first session of play today.India had declared its first innings at 566-8 in reply to New Zealand’s first innings score of 193.New Zealand, resuming at 24-1, suffered an early setback as last match’s double-centurion Brendon McCullum was trapped lbw by Ojha for 25, adding just 10 runs this morning.After dismissing McCullum with the last delivery of his second over, Ojha struck again with the first one of his third.Martin Guptill was given lbw by umpire Simon Taufel, but replays showed that the ball had pitched well outside leg-stump. New Zealand fell to 38-3 and could not wriggle out of the grip of the spinners as Harbhajan replaced Ojha in the attack.Harbhajan dismissed night-watchman Gareth Hopkins when Gautam Gambhir took a fine bat-pad catch lunging to his right at short-leg. He also got the wicket of Ross Taylor, caught by substitute Cheteshwar Pujara in the same position, but the batsman was not happy with the bat-pad decision.Kane Williamson was clean bowled by Ishant and then Raina came on to bag two wickets in two overs with his innocuous off-spin. Jesse Ryder, batting with a runner due to a calf injury, gave a catch to Sharma at mid-off. Raina then trapped captain Daniel Vettori lbw.advertisementlast_img read more