Quantum electrodynamics (QED), is a fundamental scientific theory that is also known as the quantum theory of light. Because Feynman diagrams allow physicists to depict subatomic processes and develop theories regarding particle interactions, the diagrams have become an indispensable and widely used tool in particle physics.įeynman diagrams derive from QED theory. Moreover, Feynman diagrams allow visual representation and calculation of the ways in which particles can interact through the exchange of virtual photons and thereby provide a tangible picture of processes outside the human capacity for observation. With regard to QED theory, Feynman is perhaps best remembered for his invention of what are now known as Feynman diagrams, to portray the complex interactions of atomic particles. If higher order diagrams (integrals) are sufficiently smaller than lower order diagrams, then the series is perturbative.American physicist Richard Feynman ’s (1918 –1988), work and writings were fundamental to the development of quantum electrodynamic theory (QED theory). They also represent the lowest order diagram in a series of diagrams with successively more particles exchanged.Īs each diagram represents the integral for a matrix element, the series of diagrams corresponds to a series of integrals that must be summed to get the entire matrix element. They represent the most basic interaction that transforms the initial state into the final state, and therefore normally involve the exchange of only one photon or one fermion. The Feynman diagrams we have looked at thus far are known as "tree" diagrams. We say that virtual particles are "off the mass shell" while real particles are "on the mass shell". Since virtual particles exist for only a finite time, their energy is uncertain, and the mass is part of the energy of the particle. Giving up the defined mass is justified by Heisenberg's uncertainty relation, DE Dt > hbar/2. This process cannot occur in vacuum for a real massless photon, and conserve energy and momentum simultaneously, as you will demonstrate in a homework problem. This can be readily seen by considering the diagram for a single photon producing an e +e - pair. Virtual particles can have a mass that is different from the mass of their real counterparts. What we give up is the "mass constraint" on virtual particles. However, in doing so we must give up something. It is standard convention to impose energy and momentum conservation at each vertex. Notice that in these processes, the exchanged particle is an electron (fermion) not a photon (boson).Īny particle in a Feynman diagram that is not part of the initial or final state is called a virtual particle. Pair Annihilation, Pair Production, and Compton ScatteringĪ valid Feynman diagram can be reflected and twisted to produce other valid Feynman diagrams.Īn example of this process is given by the three basic diagrams for the processes of pair annihilation, pair production, and Compton scattering. Let's look at some examples, beginning with Bhabha scattering.īhabha scattering is named for the Indian physicist who first calculated the process. Many complex processes can be built from this basic QED vertex. We draw an arrow on the lines to indicate the time sense of the fermion.Īn arrow pointing forward in time identifies that line as a particle.Īn arrow pointing backward in time identifies that line as an antiparticle. The two fermion lines are part of a single, unbroken line. In Quantum Electrodynamics (QED) the basic interaction vertex is the junction of two fermion lines with a photon. This is enough to start with, let's use these to look at a more complex interaction. Lines should be labeled to avoid confusion.Photons are represented by wavy lines, gluons by loopy lines, and Z° or W ± by either wavy lines or dashed lines. Bosons are drawn as dashed lines, wavy lines, or loopy (helix or spring-like) lines.Fermions are drawn as continuous, solid lines.Ī fermion line can end only in the initial or final states (left or right side of the diagram). ![]() (Again, some authors draw time in the vertical direction, in which case you can rotate the drawing clockwise by 90° to get our convention.) The left side of the diagram represents the initial state, and the right side represents the final state. The vertical direction represents all other spatial directions. The horizontal direction is the horizontal direction, increasing from left to right.Lecture 12 Recall from last lecture: Rules for Drawing Feynman Diagrams (version one)
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![]() At higher resolutions, DPI settings higher than 100% are supported. At 1024x768, using a DPI setting of more than 100% is not supported. Graphics adapter that supports 1024x768 or higher resolution.Windows Server 2016, Windows 10, Windows 7 Service Pack 1, Windows Server 2012 R2, Windows Server 2008 R2 SP1, Windows 8 Enterprise, Windows Server 2012, Windows 8, Windows 8.1, Windows Server 2019Ī computer with at least the following minimum configuration: Contains sample database and instructions for completing various exercises. Provides information to read before installing the MAP Toolkit, including installation prerequisites and known issues. Installation package containing the tool and SQL LocalDB. ![]() The MAP Toolkit includes the following components: MAP also provides server utilization data for Hyper-V server virtualization planning identifying server placements, and performing virtualization candidate assessments. MAP provides detailed readiness assessment reports and executive proposals with extensive hardware and software information, and actionable recommendations to help organizations accelerate their IT infrastructure planning process, and gather more detail on assets that reside within their current environment. The Microsoft Assessment and Planning Toolkit (MAP) is an agentless, automated, multi-product planning and assessment tool for quicker and easier desktop, server and cloud migrations.Microsoft Download Manager is free and available for download now. It also allows you to suspend active downloads and resume downloads that have failed. It gives you the ability to download multiple files at one time and download large files quickly and reliably. The Microsoft Download Manager solves these potential problems. You might not be able to pause the active downloads or resume downloads that have failed.Files larger than 1 GB may take much longer to download and might not download correctly. ![]() (You would have the opportunity to download individual files on the "Thank you for downloading" page after completing your download.) In this case, you will have to download the files individually.
In fact, it even comes with a display on the top for checking network speeds, data usage, battery consumption, and more. And to ensure you can expect the same speeds while accessing the internet, it offers 4G support with an inbuilt SIM card slot. Starting with its networking speeds, you can expect this car WiFi router to go up to 1000 Mbps with ease. Netgear’s Nighthawk M1 car WiFi router is present at the 2nd position in this listicle as it is the best performing option listed here. If you are familiar with networking devices like switches and WiFi routers, then you must have heard about Netgear in the past since it is known for offering all sorts of high-performance WiFi router models.
![]() Make a rice heating pad to soothe your aches. Thermotherapy (heat treatment) for treating osteoarthritis of the knee. You can learn more about how we ensure our content is accurate and current by reading our editorial policy. Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. Schedule an appointment with your doctor if muscle and joint pain persists for several days. ![]() If you’re feeling too sore to leave the house, it can also save you a trip to the store. Making your own heating pad can be cost-efficient and safer than using an electric heating pad. You can make a reusable compress by sewing two rectangles of an old pillowcase or shirt, or scraps of fabric.You can add dried herbs or florals like lavender for a relaxing scent.Fill a ziplock bag or sock with barley or oats, which will also hold heat well and mold to your body.If you need more time once the heating pad has gone cold, microwave again for 1 minute and reapply. Remove from the microwave (again, be careful, it will be hot).Microwave on high for no more than 3 minutes.Leave enough room at the top so you can close the opening by either sewing it shut or tying it with a rubber band or string - anything you think will hold the rice in. This pad works best if you use a bigger sock, like a tube sock. Well, now you can put those lonely socks to good use! If neck and shoulder pain are causing you trouble, all you need is a sock and some rice. Like most people, you probably have a drawer in your house for orphaned cotton socks. ![]() In 2021, Apple began to require mobile developers to obtain consent before collecting so-called “third-party data,” which track users between apps or websites so they can be shown targeted ads based on their online behaviour. Yes, shareholders likely pressured them last year about profitability, hence the head count reduction, but as a rapidly growing software company, I think you always want to stay as nimble as possible.” “I don’t think Shopify is doing this for shareholders, I think they always focus on the product. “Shopify had plenty of announcements last year as well, but the stock’s decline overshadowed pretty much everything else,” said Dan Romanoff, a Chicago-based senior analyst of e-commerce and software companies at Morningstar Inc., who believes a common theme this year is a renewed “focus on productivity.” Davidson, described “as an attempt to be pro-active, consistent with its long history.” Audiences, for example, positions Shopify directly against rival Inc.’s expanding advertising business and takes advantage of a potentially lucrative lull after a pullback by Apple Inc. But Shopify chose to announce them altogether, which Tom Forte, managing director and senior research analyst for investment firm D.A. The new products launched this week would typically have been spread out as individual announcements. In another recent e-mail, chief executive and Shopify founder Tobias Lutke said, reiterating what he told The Globe almost a decade ago when he was named CEO of the year: “What I’m trying to create is an environment where almost everyone around me feels uncomfortable all the time, because I’m dragging them into the next box.” He added that if the new changes “feel chaotic” for Shopify employees, it “is kind of the point.” Nejatian said in an e-mail to staff this week. “We have endless channel updates mixed with broad announcements and pineapple on pizza debates,” Mr. These changes have caused dissatisfaction among a number of employees, several said, who used the Slack channels for not only task-related conversations, but also friendly work banter.īut in an e-mail, Kaz Nejatian, who was recently promoted to become Shopify’s chief operating officer after serving as its vice-president of product, described Slack as “bloated, noisy and distracting.” According to five mid-level employees at Shopify, who The Globe is not identifying because they are not authorized to discuss the matter publicly, staff found a majority of Slack channels were deleted when they returned to work this week. Shopify plans to move its communications to Workplace by Meta Platforms Inc. But these rules only apply to “Shopifolk,” meaning Shopify staff can still set up work-related meetings with people who are not employed by the company. Thursdays will be the only day staff will be allowed to hold big meetings or events. The company now forbids all meetings from being scheduled on Wednesdays, the memos say. Shopify is also reducing its use of Slack, an instant messaging program that has long been the company’s preferred method of internal communication. The internal changes include indefinitely barring any meetings of three or more people, according to Shopify memos and e-mails obtained by The Globe and Mail. This week, employees returned after winter break to find smaller teams with tighter roles, and new rules in place. Over just a matter of days, Shopify launched a new look for its website announced a notable subscription product aimed at big retailers, called Commerce Components and bolstered a tool dubbed Audiences that will allow those businesses to pool customer data and better target advertisements. Shopify saw its stock price drop by more than two-thirds last year, and is entering 2023 with fewer employees after laying off more than 10 per cent of its workers last fall. Rising interest rates and inflation have created macroeconomic challenges, forcing many companies – big and small – to slow their hiring and get leaner. Tech companies are under pressure to tighten their operations on all fronts. ![]() The raft of changes signals an urgency and illustrates wider problems plaguing the technology sector, as an era of risk-taking gives way to sobering up amid crumbling profitability and cratering stock market valuations. The sweeping initiatives affect external and internal operations at Ottawa-based Shopify, which provides businesses in more than 170 countries with tools to set up online stores and retail point-of-sale systems. SHOP-T has made a flurry of strategic changes to kick off the new year, as the e-commerce company strives to exit a slump that sharply diminished its stock price and led to a slashing of its global work force. Safety analysis showed grade 3–4 treatment-related adverse events (TRAEs) in 47% of the immunotherapy plus chemotherapy arm versus 38% of the chemotherapy only arm, most commonly neutropenia (7 vs 9%), anaemia (6 vs 14%), diarrhoea (4 vs 1%), elevated liapse (6 vs 1%) and asthenia (1 vs 2%). “Notably, a survival benefit was observed across various patient subgroups, including populations with a high unmet medical need, such as those with CNS metastases”, report Luis Paz-Ares, from Hospital Universitario 12 de Octubre in Madrid, Spain, and co-workers in The Lancet Oncology. This compared with the median OS of 10.7 months achieved by the 358 patients who instead received four cycles of chemotherapy, giving a significant hazard ratio (HR) for death of 0.69 in favour of immunotherapy use.Īfter a further 3.5 months of median follow-up, median OS continued to be significantly better with immunotherapy plus chemotherapy than chemotherapy alone, at 15.6 versus 10.9 months and a HR of 0.66.įorest plot analysis of OS favoured the immunotherapy regimen across the prespecified subgroups, including by PD–L1 expression, with the exceptions of patients aged at least 75 years and never smokers. When combined with the combination’s “favourable risk–benefit profile”, the investigators say their “data support this regimen as a new first-line treatment option for patients with advanced NSCLC.”įollowing positive phase II study results, the researchers further investigated the hypothesis that use of chemotherapy could “provide rapid disease control” while the benefits of immunotherapy can take hold.Īt the prespecified interim analysis, after a median follow-up of 9.7 months, the primary endpoint of OS was a median 14.1 months for the 361 patients who were randomly assigned to receive nivolumab 360 mg every 3 weeks plus ipilimumab 1 mg/kg every 6 weeks, combined with two cycles of a histology-driven regimen of platinum-based doublet chemotherapy. ![]() ![]() MedwireNews: Use of nivolumab plus ipilimumab alongside chemotherapy significantly improved overall survival (OS) for treatment-naïve, stage IV or recurrent non-small-cell lung cancer (NSCLC) patients in the CheckMate 9LA trial compared with chemotherapy alone. Author: By Lynda Williams, Senior medwireNews Reporter ![]() ![]() If the Ace of Clubs is surrounded by Spades, it can show someone who is weak-willed, and unable to follow-through on their plans. The surrounding cards will usually offer a clue about the choice. When the Ace of Clubs falls in a reading about someone's intentions, it shows that they have already made up their mind on a course of action, and have no intentions of deviating from their chosen direction. It is the manifestation and desire to attain riches money in the mortal coil no matter what stands in. It also expresses the fears that we have when it comes to the material realm of earth. Cartomancy and The 2 of Spades Twos represent fear that comes along with partnerships and relationships. This card shows a personal choice backed by determination. The True Meaning of 2 of Spades in Cartomancy. The Ace of Clubs can represent a legal will, and it can also represent one's personal power of will. The King of Spades must appear in the combination to show "duty." Queens in place of the Kings would indicate that it's a female. If the Ace of Clubs falls first, it would show being conscripted into the military. The combination Any King + King of Spades + Ace of Clubs would show someone joining the military. The combination Any King + King Spades + 4 of Spades would show someone being arrested. If the Ace of Clubs is nearby, the combination could refer to a soldier. In many cultures the girl was expected to bring along a dowry as well, to add to. You could lift your social status by marrying your daughter off to noble family, or to a wealthy landowner. In olden days, marriages were often arranged based on money and prestige. Two Kings falling together would generally indicate a police officer. In traditional cartomancy, the Ace of Clubs is the card of marriage. In fact, this card can even represent the military. Here are a few fun combinations to consider.Īce of Clubs + 2 of Hearts = elementary school, nursery school, or dance studioĪce of Clubs + 3 of Hearts = beauty salon, flower shopĪce of Clubs + 5 of Hearts = furniture store, clothing store, department storeĪce of Clubs + 4 of Spades = a hospital, or jailĪce of Clubs + 7 of Spades = a bar (with the 2 of Hearts to show dancing = nightclub)Īce of Clubs + 8 of Spades = doctor's office, dentists office, medical clinicĪce of Clubs + King of Spades + any other King = police station, also joining the militaryĪce of Clubs + Ace of Diamonds = the post officeĪce of Clubs + 2 of Diamonds = a restaurantĪce of Clubs + 5 of Diamonds = the courthouse, shopping centerĪce of Clubs + King of Diamonds = a college or universityĪce of Clubs + 3 of Clubs = garden center, barbershopĪce of Clubs + 6 of Clubs = a bookstore, a factory (manufacturing plant)Īce of Clubs + 8 of Clubs = the building where you workĪce of Clubs + 9 of Clubs = a passport, but it can also represent a hotelĪnother way to look at it would be to consider that the Ace of Clubs refers to a service organization, whether it's a retail shop or a large corporation or a staunch institution. The Ace of Hearts is the home, but the Ace of Clubs can represent anything from a friend's house, to the workplace, to a commercial establishment, to a large institution. The Ace of Clubs also retains the meaning of "property," and it's the card that represents "a building" in Modern Cartomancy. With the 2 of Hearts, representing a child, it would show a legal adoption. With the 10 of Clubs, it would show signing papers on a business. With the Ace of Hearts, the Ace of Clubs can denote a contract to buy or sell a home. ![]() The Ace of Clubs does retain its meaning as a "binding contract." The primary meanings for this card include important papers, a legal document, and a contract to be signed. These days, most marriages are based on love, and may be better represented by cards in the suit of Hearts. It is perhaps for this reason that the Ace of Clubs in modern cartomancy has lost the meaning of marriage. Today very few marriage are arranged this way in the western world. Based on the marriage contract she was usually considered to be the property of her new husband. Spades, the worst of all, signify grief, sickness, and loss of money. ![]() Ace of Diamonds: A gift of jewelry, a letter or message, improvement2 of Diamonds. In many cultures the girl was expected to bring along a dowry as well, to add to the husband's holdings. Then comes the King, followed by the Queen. Spades: Improvement, small wins, upswing7 of Spades: Bad advice, grief. Meaningful combinations and relations between cards in a spread have collective meanings which give increased insight into problems and situations.In traditional cartomancy, the Ace of Clubs is the card of marriage. ![]() Mike Mettler: If someone unfamiliar with your work on vinyl wants to find out what George Winston music is all about, what album of yours should they put the needle down on first, and why? Herewith, Winston and I discuss how he first came up with that folk piano playing style, how The Doors became one of his major influences in addition to his favorite New Orleans jazz players, and the key differences between what his left and right hands were charged with doing on the piano. ![]() The balance of that interview has never been posted or published anywhere - until now, that is. The pianist’s final LP, Night, was released on vinyl via RCA/Dancing Cat in May 2022, and it’s a fitting cap on a truly admirable career that features a score of stunning tracks like the haunting cover of Leonard Cohen’s perennially affecting “Hallelujah” and literal time-of-day period-piece Winston originals like “At Midnight” and “Dawn.”ĭuring April 2017, Winston and I conducted the aforementioned 65-minute phone interview that was initially intended mainly to discuss his then-new RCA album titled Spring Carousel - at present, a CD/digital-only album that needs to be released on vinyl, STAT! - but, inevitably, we wound up speaking quite at length about his detailed recording techniques and related analog proclivities. Thankfully, Winston’s own special way enabled our collective ears to enjoy 50-plus years of great-sounding recordings and live performances alike. I could hear a scratchy thing on a voicemail or something on a great stereo or in a studio room and I’m still thinking, ‘Well, there’s an E flat sharp.’ Other than with Jim Morrison, I can’t ever remember listening to the lyric of a song because I’m always listening to the chords, and I’m listening to the notes. “Wherever he wants the mikes, wherever he wants to record, and wherever he wants the piano to be - I leave all of that up to him. “I leave a lot of the recording-related decisions up to my engineer, Howard Johnston,” he confirmed. ![]() he outlined to me in a phone interview we conducted together back in April 2017. Winston also had an ear for what made for both high-quality performances and stellar playback on vinyl, an overall SQ M.O. Many of these intimate, RTI-pressed, one-man solo acoustic piano LPs went platinum, and they essentially put the burgeoning Windham Hill Records label on the map. For his part, Winston begat an instrumental artform initially known as “folk piano,” best exemplified by seasonally flavored LPs like 1980’s Autumn, 1982’s December, and 1982’s Winter Into Spring. Photo courtesy Winston’s official site.Īfter a decade-long battle with cancer, pioneering pianist/instrumentalist extraordinaire George Winston sadly passed away at age 73 on June 4, 2023. Autumn Leaves Us: Above, the late, great George Winston, doing what he did best. ![]() Windows 9x and Word 9x at 800圆00 resolution. Show HN: Van, truck or car camp for $0 a night () 341 points by chaseadam17 2 days ago | 224 comments. Whatnot is the largest livestream shopping platform in the U.S.345 points by sturza 2 days ago | 155 comments. Behavior improvement platform for kids with ADHD, Autism, & Anxiety. Product Engineer ( UI/UX ) The game where everyone creates together. Based on the figures made available on the website, the base model was $39,347.Hacker NewsParker is a digital bank. Out of interest, I picked a random car to compare with. randomdata 1 hour ago | parent | next > there is barely any meaningful pricing difference between the cheapest iPhone 15 (950EUR) and iPhone 15 Pro (1200EUR). Show HN: Primo – a visual CMS with Svelte blocks. Managing Kitchen Fruit Flies with a Little Shop of Horrors. Using Prolog in Windows NT Network Configuration (1996) Employees Bid on Anchor Brewery. Links for the intellectually curious, ranked by readers. At the links below you'll find directories of companies started by historically underrepresented founders.345 points by sturza 2 days ago | 155 comments. In this directory, you can search for YC companies by industry, region, company size, and more. Since 2005, we have invested in over 4,000 companies that have a combined valuation of over $600B. Michael Seibel was chief executive of Y Combinator’s accelerator up until 2020, when the accelerator evolved from a more traditional partnership to no longer having multiple CEOs. Given the accelerator’s growth, competitive tensions feel nearly. ![]() We give startups a huge fundraising advantage.Hacker NewsSince inception, Y Combinator has invested in thousands of startups, and more recently, even hundreds within a single batch. 4% of YC companies have become billion dollar companies. 18% of YC companies are valued at $100M+. 39% of YC companies have raised a Series A. We improve the success rate of our startups. ![]() 42% of YC's billion dollar companies applied with only an idea. Since inception, Y Combinator has invested in thousands of startups, and more recently, even hundreds within a single batch.This concern is also important because benchmarks like HumanEval don. Without this, developers don't get much utility from the model. ![]()
When you say, “Alexa,” a blue bar will appear on the screen to indicate that your device is processing your request and is streaming to the cloud. Fire HD 10 and Alexa are designed with privacy in mind. Alexa hands-free-With always-ready, hands-free access to Alexa, you can easily control video and music playback, launch apps, get news and sports scores, manage your smart home devices, make a video call, and even enable Show Mode to transform your tablet into an Echo Show experience.Listen via built-in speakers, or connect speakers or headphones via Bluetooth or the headphone jack. Immersive Dolby Atmos audio-Videos, games, and web content sound amazing.You can check your social media accounts while watching a movie, take a video call on Zoom while sending a message, or take notes in OneNote while reading a Kindle book. Split screen-An all-new feature for Fire OS shows two compatible apps like Messenger from Facebook and Prime Video, side-by-side for easy multi-tasking.Stay productive-Check email, chat with a co-worker, easily view or download a file, update shopping lists, and set calendar reminders using apps like Office, Outlook, OneNote, Microsoft Teams, Notepad, and Dropbox.Stay connected-2MP front-facing camera is landscape oriented to support widescreen video calls with friends and family-simply ask Alexa to make a call, or use apps like Zoom, Skype, and Microsoft Teams.Stay entertained-Access millions of movies, TV shows, songs, books, apps, and games on your tablet.Plenty of storage-Available with 32GB or 64GB of internal storage, plus support for up to 1TB of expandable storage via a microSD card, there’s plenty of space for your photos, videos, and apps.All-day battery life-Up to 12 hours of battery life for browsing the web, watching videos, listening to music, and more.Updated design-Thinner and lighter design than the previous generation with uniform bezels, and a screen strengthened with aluminosilicate glass.Stunning display-Vivid 10.1”, 1080p Full HD display is 10% brighter than the previous generation with more than two million pixels.Fast and responsive-Powerful octa-core 2.0 GHz processor and 3GB RAM, with 50% more RAM than the previous generation for fast performance and app starts. ![]() “Plus, we added new apps, features, and accessories, including a Productivity Bundle with the Fire HD 10, a Microsoft 365 Personal subscription, and a detachable keyboard case, to help you get more done.”įor just $149.99, the all-new Fire HD 10 features: The new Fire HD 10 is brighter, thinner, and lighter, with an octa-core processor for fast and responsive performance, 50% more RAM, and all-day battery life-and is still only $149.99,” said Kevin Keith, vice president, Amazon Devices. “Our best tablets just keep getting better. View the full release here: įire HD 10 is offered in Black, Denim, Lavender, and Olive colors. Plus, with the Fire HD 10 Productivity Bundle, customers can get more done with a detachable keyboard case and a Microsoft 365 Personal subscription. Amazon also introduced an all-new Fire HD 10 Kids tablet for kids ages 3-7, and new Fire Kids Pro tablets built with 6-12 year-olds in mind-learn more here ( This press release features multimedia. 27, 2021- (NASDAQ: AMZN)-Amazon today announced the next generation of Fire HD 10 tablets-the all-new Fire HD 10 and first Fire HD 10 Plus offer powerful performance, a brighter full HD display, updated design, and features to help customers stay entertained, connected, and productive. ![]() ![]() Fire HD 10 features a powerful octa-core processor, now with 50% more RAM, a brighter Full HD display, an updated design, 12 hours of battery life, and up to 64GB of internal storage expandable to 1TB via a microSD card-all for just $149.99įire HD 10 Plus is our most powerful 10-inch tablet ever, packed with all the features of Fire HD 10 plus 4GB RAM, wireless charging, and a soft touch finish for $179.99įire HD 10 Productivity Bundle includes a custom-designed, detachable keyboard case and 12-month subscription to Microsoft 365 Personal-with premium Office apps, 1TB of OneDrive cloud storage, and more-for only $219.99 |
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