https://en.wikipedia.org/wiki/History_of_numerical_weather_prediction
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In 1922, Lewis Fry Richardson published the first attempt at forecasting the weather numerically. Using a hydrostatic variation of Bjerknes’s primitive equations,[2] Richardson produced by hand a 6-hour forecast for the state of the atmosphere over two points in central Europe, taking at least six weeks to do so.[3] His forecast calculated that the change in surface pressure would be 145 millibars (4.3 inHg), an unrealistic value incorrect by two orders of magnitude. The large error was caused by an imbalance in the pressure and wind velocity fields used as the initial conditions in his analysis.[2] The first successful numerical prediction was performed using the ENIAC digital computer in 1950 by a team led by American meteorologist Jule Charney. The team include Philip Thompson, Larry Gates, and Norwegian meteorologist Ragnar Fjørtoft, applied mathematician John von Neumann, and computer programmer Klara Dan von Neumann, M. H. Frankel, Jerome Namias, John C. Freeman Jr., Francis Reichelderfer, George Platzman, and Joseph Smagorinsky.[5][6][7] They used a simplified form of atmospheric dynamics based on solving the barotropic vorticity equation over a single layer of the atmosphere, by computing the geopotential height of the atmosphere’s 500 millibars (15 inHg) pressure surface.[8] This simplification greatly reduced demands on computer time and memory, so the computations could be performed on the relatively primitive computers of the day.[9] When news of the first weather forecast by ENIAC was received by Richardson in 1950, he remarked that the results were an “enormous scientific advance.”[2] The first calculations for a 24‑hour forecast took ENIAC nearly 24 hours to produce,[2] but Charney’s group noted that most of that time was spent in “manual operations”, and expressed hope that forecasts of the weather before it occurs would soon be realized.[8]
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Posts Tagged ‘quote’
History of numerical weather prediction – Wikipedia
December 29, 2021President Biden Announces New Actions to Protect Americans Against the Delta and Omicron Variants as We Battle COVID-19 this Winter | The White House
December 21, 2021QT:{{”
Expanding Free At-Home Testing for Americans: Today, the President will announce new steps to ensure that Americans has access to free at-home testing. First, the more than 150 million Americans with private insurance – who now are able to get tests covered in physician offices, pharmacies, and clinics with no cost sharing – will also be able to get at-home tests reimbursed by their insurance.
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Turkey Without Covid – The New York Times
December 19, 2021QT:{{”
The most widely available antigen test seems to be BinaxNOW, from Abbott. You should also feel comfortable using QuickVue, Ellume and Flowflex, among others.
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https://www.nytimes.com/2021/11/24/briefing/thanksgiving-covid-rapid-test.html
COVID antiviral pills: what scientists still want to know
December 18, 2021QT:{{”
Molnupiravir acts by introducing mutations into the viral genome during viral replication. A metabolite of the drug is picked up by a viral enzyme called RNA-dependent RNA polymerase and incorporated into the viral genome, eventually causing so many errors that the virus can no longer survive.
…
Paxlovid acts by inhibiting an enzyme that’s needed to process some viral proteins into their final, functional form. But the drug is a combination of an antiviral and another drug, called ritonavir, which helps to prevent enzymes in the liver from breaking down the antiviral before it has a chance to disable the coronavirus. Ritonavir, a component of some HIV treatment cocktails, can affect how some other medications are metabolized by the body.
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Molnupiravir & Paxlovid
https://www.nature.com/articles/d41586-021-03074-5
Photography Pricing Guide – How much do Photographers make in 2021
November 27, 2021https://www.pixpa.com/blog/photography-pricing-guide
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Rates Based on Level of Experience
Experience is a significant factor in deciding how much does a photographer makes. Photography prices are typically based on the level of knowledge and experience, as indicated below.
Amateurs and Hobbyists – Amateurs and hobbyists commonly charge $25-$75 an hour for images normally used on blogs, small websites, or for local advertising. The fee is generally under $100. However, they may not follow standard photography practices and have other lines of work.
Student Photographers – Students typically have more experience than amateurs and hobbyists in that they’ve received some form of training. Their typical hourly rate is $50 – $100 per hour. Prices of student photographers can vary based several factors – the school that they are studying in, the stage of their education, whether they have worked with and assisted other professional photographers, and, last but not least, their photography portfolio. Students with brilliant student photography portfolios can command the same rates as professional photographers.
Entry-Level Photographers – The entry-level or semi-professional photographers charge $50-$150 per hour or $25-$125 per image. They’re not as committed and often have other lines of work that they rely on.
Professional Photographers with experience – Professional, experienced photographers usually charge $75 – $250 per hour or per image. They rely solely on their photography work to make a living and typically have invested a lot in their equipment, and have more experience in both the pre-production and post-production stages of photography.
Top Professional Photographers – Top professional photographers, known as high-end photographers, charge $250 – $500 per hour or $200 -$1200 per image. This elite group of photographers command top dollar for their work and can even be paid up to $10,000 per day depending on their area of specialty. They cover areas such as sports, fashion, entertainment, film, documentaries for TV, movies, billboards or magazines.
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Machine-learning-assisted modeling: Physics Today: Vol 74, No 7
November 23, 2021QT : {{”
One of the most successful applications of machine learning to scientific modeling is in MD. Researchers study the properties of materials and molecules by using classical Newtonian dynamics to track the nuclei in a system. One critical issue in MD is how to model the PES that describes the interaction between the nuclei. Traditionally, modelers have dealt with the problem in several ways. One approach, ab initio MD, was developed in 1985 by Roberto Car and Michele
Parrinello7 and computes the interatomic forces on the fly using models based on first principles, such as density functional theory.8 Although the approach accurately describes the system under
consideration, it‘s computationally expensive: The maximum system size that one can handle is limited to thousands of atoms. Another approach uses empirical formulas to model a PES. The method is efficient, but guessing the right formula that can model the PES accurately enough is a difficult task, particularly for complicated systems, such as multicomponent alloys. In 2007 Jörg Behler and Parrinello introduced the idea of using neural networks to model the PES.9 In that new paradigm, a quantum mechanics model generates data that are used to train a neural-network-based PES model.
7. R. Car, M. Parrinello, Phys. Rev. Lett. 55, 2471 (1985).
https://doi.org/10.1103/PhysRevLett.55.2471
9. J. Behler, M. Parrinello, Phys. Rev. Lett. 98, 146401 (2007). https://doi.org/10.1103/PhysRevLett.98.146401
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https://physicstoday.scitation.org/doi/10.1063/PT.3.4793
mentions Parrinelllo classic paper :
#8 has QM & NN (NN models for PES)
Reddit – shortcuts – Send links from chrome to safari in iphone
October 25, 2021QT:{{”
Not a shortcut but check out Opener. It is well worth a couple bucks for the functionality it adds to your phone.
https://apps.apple.com/us/app/opener-open-links-in-apps/id989565871 “}}
https://www.reddit.com/r/shortcuts/comments/kovwoi/send_links_from_chrome_to_safari_in_iphone/
Computational scientists look for lessons learned from the COVID-19 pandemic
September 19, 2021https://cen.acs.org/physical-chemistry/computational-chemistry/Computational-scientists-look-lessons-learned/99/i28
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One computational achievement stands out from the rest—models of the virus’s proteins. In February 2020, with the virus spreading rapidly around the world, structural biologist Jason S. McLellan at the University of Texas at Austin and colleagues at the National Institutes of Health used cryo-electron microscopy (cryo-EM) to make detailed structures of SARS-CoV-2’s spike protein. The virus uses the spike protein to attach to and enter human cells. This protein is a major target for drugs and vaccines. Within weeks of McLellan’s team publishing the cryo-EM data, Rommie Amaro’s group at the University of California San Diego used those structures to create the first computer models of the protein using artificial intelligence and other computational techniques.
In the months that followed, the group used those tools to make more-highly-detailed models of the spike protein. For example, the researchers modeled what the sugars that dot the protein’s surface look like—a feature that cryo-EM can’t capture but that is important for understanding how antibodies or drugs may interact with the protein. Their simulations also showed how the protein’s shape changes to reveal its receptor-binding domain, a region that scientists want to target with therapeutics. The work won Amaro’s group a special kind of Gordon Bell Prize, one of the most prestigious awards in
supercomputing.
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10+ Best “A Beautiful Mind” Movie Quotes | Quote Catalog
September 18, 2021QT:{{”
“George Mackey: How could you, a mathematician, a man devoted to reason and logical proof, how could you believe that extraterrestrials are sending you messages?
Steve Nash: Because the ideas I had about supernatural beings came to me the same way that my mathematical ideas did. So I took them seriously.”
— George Mackey, Steve Nash, A Beautiful Mind
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