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Best Lenovo Black Friday 2018 deals: ThinkPad laptops and more

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Lenovo 2018 Black Friday ad

The world’s biggest PC maker has elaborate plans for its online store come Black Friday, with Lenovo promising laptop doorbusters nearly each hour from early on Thanksgiving morning through the end of Black Friday itself. Here’s a breakdown of those deals — highlighted by a $99 IdeaPad 130s special — along with Black Friday specials on Lenovo laptops from other retailers.

Thanksgiving

10 a.m.
ThinkPad X1 Yoga (Intel Core i7 processor, 16GB RAM, 512GB SSD, 14-inch touchscreen): $1,499.99

11 a.m.
Thinkpad X1 Carbon (Core i7-7500U, 16GB RAM, 512GB SSD, 14-inch full HD display): $1,139.99

1:00 p.m.
IdeaPad 130 (Core i3, 4GB RAM, 500GB hard drive, 15.6-inch display): $299.99

3:00 p.m.
Flex 2-in-1 (Intel Pentium, 4GB RAM, 128GB SSD, 14.1-inch display): $399.99

4:00 p.m.
IdeaPad 330 (Core i5, 8GB RAM, 1TB hard drive, 15.6-inch display): $599.99

6:00 p.m.
IdeaPad 130 (Core i7, 8GB RAM, 1TB, 15.6-inch display): $529.99

7:00 p.m.
ThinkPad E575 (AMD A10-9600P, 8GB RAM, 500GB, 15.6-inch display): $399.99

8:00 p.m.
ThinkPad T480 (Core i5, 8GB RAM, 512GB SSD, 14-inch display): $779.99

9:00 p.m.
IdeaPad 530 (Core i7, 8GB RAM, 256GB SSD, 15.6-inch display): $699.99

11:00 p.m.
IdeaPad 330 (Core i7, 16GB RAM, 128GB SSD, 15.6-inch display): $879.99

Midnight
IdeaPad 130s (Intel Celeron N4000, 2GB, 32GB SSD): $99
IdeaPad 330 (Core i5, 8GB RAM, 1TB hard drive, 15.6-inch display): $399.99

Black Friday

8 a.m.
ThinkPad X1 Yoga (Core i7 processor, 16GB RAM, 512GB SSD, 14-inch touchscreen): $1,2499.99

9 a.m.
Thinkpad X1 Carbon (Core i7-7500U, 8GB RAM, 512GB SSD, 14-inch full HD display): $899.99

1:00 p.m.
Yoga 720 2-in-1 (Core i3, 4GB RAM, 128GB SSD, 12-inch full HD touchscreen): $599.99

4:00 p.m.
ThinkPad L380 Yoga (Core i5, 8GB RAM, 512GB SSD, 13.3-inch touchscreen): $779.99

6:00 p.m.
Flex 6 2-in-1 (Core i5, 8GB RAM, 256GB SSD, 14.1-inch touchscreen): $649.99

Lenovo’s website isn’t the only place to find deals on its laptops. Here are a selection from other retailers if you’re shopping elsewhere on Black Friday.

Best Buy

130-15AST (AMD A6, 4GB, 500GB hard drive, 15.6-inch display): $199.99
Chromebook MT8173c 2-in-1 (MediaTek processor, 4GB RAM, 32GB SSD, 11.6-inch touchscreen): $179.99

Costco

IdeaPad 330 (Core i5, 12GB, 1TB hard drive, 15.6-inch touchscreen): $449.99

Microsoft Store

Flex 2-in-1 (Core i5, 8GB, 128GB SSD, 14-inch full HD touchscreen): $499

Office Depot and OfficeMax

Flex 5 2-in-1 (Core i5, 8GB, 1TB hard drive, 15.6-inch full HD touchscreen): $499.99

Staples

330s (AMD Ryzen 7, 8GB, 1TB hard drive, 15.6-inch full HD display): $469.99

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Science

How do painkillers kill pain? It’s about meeting the pain where it’s at

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Enlarge / A variety of pain-relieving drugs are available both over the counter and by prescription.

Without the ability to feel pain, life is more dangerous. To avoid injury, pain tells us to use a hammer more gently, wait for the soup to cool or put on gloves in a snowball fight. Those with rare inherited disorders that leave them without the ability to feel pain are unable to protect themselves from environmental threats, leading to broken bones, damaged skin, infections, and ultimately a shorter life span.

In these contexts, pain is much more than a sensation: It is a protective call to action. But pain that is too intense or long-lasting can be debilitating. So how does modern medicine soften the call?

As a neurobiologist and an anesthesiologist who study pain, this is a question we and other researchers have tried to answer. Science’s understanding of how the body senses tissue damage and perceives it as pain has progressed tremendously over the past several years. It has become clear that there are multiple pathways that signal tissue damage to the brain and sound the pain alarm bell.

Interestingly, while the brain uses different pain signaling pathways depending on the type of damage, there is also redundancy to these pathways. Even more intriguing, these neural pathways morph and amplify signals in the case of chronic pain and pain caused by conditions affecting nerves themselves, even though the protective function of pain is no longer needed.

Painkillers work by tackling different parts of these pathways. Not every painkiller works for every type of pain, however. Because of the multitude and redundancy of pain pathways, a perfect painkiller is elusive. But in the meantime, understanding how existing painkillers work helps medical providers and patients use them for the best results.

Anti-inflammatory painkillers

A bruise, sprain, or broken bone from an injury all lead to tissue inflammation, an immune response that can lead to swelling and redness as the body tries to heal. Specialized nerve cells in the area of the injury called nociceptors sense the inflammatory chemicals the body produces and send pain signals to the brain.

Common over-the-counter anti-inflammatory painkillers work by decreasing inflammation in the injured area. These are particularly useful for musculoskeletal injuries or other pain problems caused by inflammation such as arthritis.

Nonsteroidal anti-inflammatories like ibuprofen (Advil, Motrin), naproxen (Aleve), and aspirin do this by blocking an enzyme called COX that plays a key role in a biochemical cascade that produces inflammatory chemicals. Blocking the cascade decreases the amount of inflammatory chemicals, and thereby reduces the pain signals sent to the brain. While acetaminophen (Tylenol), also known as paracetamol, doesn’t reduce inflammation as NSAIDs do, it also inhibits COX enzymes and has similar pain-reducing effects.

Prescription anti-inflammatory painkillers include other COX inhibitors, corticosteroids, and, more recently, drugs that target and inactivate the inflammatory chemicals themselves.

Because inflammatory chemicals are involved in other important physiological functions beyond just sounding the pain alarm, medications that block them will have side effects and potential health risks, including irritating the stomach lining and affecting kidney function. Over-the-counter medications are generally safe if the directions on the bottle are followed strictly.

Corticosteroids like prednisone block the inflammatory cascade early on in the process, which is probably why they are so potent in reducing inflammation. However, because all the chemicals in the cascade are present in nearly every organ system, long-term use of steroids can pose many health risks that need to be discussed with a physician before starting a treatment plan.

Topical medications

Many topical medications target nociceptors, the specialized nerves that detect tissue damage. Local anesthetics, like lidocaine, prevent these nerves from sending electrical signals to the brain.

The protein sensors on the tips of other sensory neurons in the skin are also targets for topical painkillers. Activating these proteins can elicit particular sensations that can lessen the pain by reducing the activity of the damage-sensing nerves, like the cooling sensation of menthol or the burning sensation of capsaicin.

Certain topical ointments, like menthol and capsaicin, can crowd out pain signals with different sensations.
Enlarge / Certain topical ointments, like menthol and capsaicin, can crowd out pain signals with different sensations.

Because these topical medications work on the tiny nerves in the skin, they are best used for pain directly affecting the skin. For example, a shingles infection can damage the nerves in the skin, causing them to become overactive and send persistent pain signals to the brain. Silencing those nerves with topical lidocaine or an overwhelming dose of capsaicin can reduce these pain signals.

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How many calories will the Tour de France winner burn?

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Enlarge / Jumbo-Visma team’s Belgian rider Wout Van Aert cycles to the finish line during the first stage of the 109th edition of the Tour de France cycling race in Copenhagen, Denmark, on July 1, 2022.

Imagine you begin pedaling from the start of Stage 12 of this year’s Tour de France. Your very first task would be to bike approximately 20.6 miles (33.2 km) up to the peak of Col du Galibier in the French Alps while gaining around 4,281 feet (1,305 m) of elevation. But this is only the first of three big climbs in your day. Next you face the peak of Col de la Croix de Fer and then end the 102.6-mile (165.1-km) stage by taking on the famous Alpe d’Huez climb with its 21 serpentine turns.

On the fittest day of my life, I might not even be able to finish Stage 12—much less do it in anything remotely close to the five hours or so the winner will take to finish the ride. And Stage 12 is just one of 21 stages that must be completed in the 24 days of the tour.

I am a sports physicist, and I’ve modeled the Tour de France for nearly two decades using terrain data—like what I described for Stage 12 – and the laws of physics. But I still cannot fathom the physical capabilities needed to complete the world’s most famous bike race. Only an elite few humans are capable of completing a Tour de France stage in a time that’s measured in hours instead of days. The reason they’re able to do what the rest of us can only dream of is that these athletes can produce enormous amounts of power. Power is the rate at which cyclists burn energy and the energy they burn comes from the food they eat. And over the course of the Tour de France, the winning cyclist will burn the equivalent of roughly 210 Big Macs.

Cycling is a game of watts

To make a bicycle move, a Tour de France rider transfers energy from his muscles, through the bicycle and to the wheels that push back on the ground. The faster a rider can put out energy, the greater the power. This rate of energy transfer is often measured in watts. Tour de France cyclists are capable of generating enormous amounts of power for incredibly long periods of time compared to most people.

For about 20 minutes, a fit recreational cyclist can consistently put out 250 watts to 300 watts. Tour de France cyclists can produce over 400 watts for the same time period. These pros are even capable of hitting 1,000 watts for short bursts of time on a steep uphill—roughly enough power to run a microwave oven.

But not all of the energy a Tour de France cyclist puts into his bike gets turned into forward motion. Cyclists battle air resistance and frictional losses between their wheels and the road. They get help from gravity on downhills but they have to fight gravity while climbing.

I incorporate all of the physics associated with cyclist power output as well as the effects of gravity, air resistance and friction into my model. Using all that, I estimate that a typical Tour de France winner needs to put out an average of about 325 watts over the roughly 80 hours of the race. Recall that most recreational cyclists would be happy if they could produce 300 watts for just 20 minutes!

Turning food into miles

So where do these cyclists get all this energy from? Food, of course!

But your muscles, like any machine, can’t convert 100 percent of food energy directly into energy output—muscles can be anywhere between 2 percent efficient when used for activities like swimming and 40 percent efficient in the heart. In my model, I use an average efficiency of 20 percent. Knowing this efficiency as well as the energy output needed to win the Tour de France, I can then estimate how much food the winning cyclist needs.

Top Tour de France cyclists who complete all 21 stages burn about 120,000 calories during the race—or an average of nearly 6,000 calories per stage. On some of the more difficult mountain stages—like this year’s Stage 12—racers will burn close to 8,000 calories. To make up for these huge energy losses, riders eat delectable treats such as jam rolls, energy bars, and mouthwatering “gels” so they don’t waste energy chewing.

Tadej Pogačar won both the 2021 and 2020 Tour de France and weighs only 146 pounds (66 kilograms). Tour de France cyclists don’t have much fat to burn for energy. They have to keep putting food energy into their bodies so they can put out energy at what seems like a superhuman rate. So this year, while watching a stage of the Tour de France, note how many times the cyclists eat—now you know the reason for all that snacking.

This article is republished from The Conversation under a Creative Commons license. Read the original article. You can subscribe to The Conversation’s newsletter here.

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How to go from eating mosquitos in Siberia to leading a NASA mission

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Enlarge / Lindy Elkins-Tanton, second from left, and colleagues in Siberia.

Scott Simper / ASU

Lindy Elkins-Tanton is a Siberian-river-running, arc-welding, code-writing, patent-holding, company-founding, asteroid-exploring, igneous petrologist professor. At various times, she has been a farmer, a trainer of competition sheepdogs, a children’s book author, and a management consultant for Boeing Helicopters. She’s currently a professor at Arizona State University, she helps run a learning company, and she is the principal investigator for NASA’s “Psyche” mission to a metal asteroid.

Her self-described “curvy” career path has taken her research into planet formation, magma oceans, mass extinctions, and mantle melting. The results she’s generated have been foundational and have earned her a constellation of prestigious awards. There is even an asteroid—Asteroid 8252 Elkins-Tanton—named after her.

Given all that, perhaps the biggest revelation in her new autobiography, A Portrait of the Scientist as a Young Woman, is that this stellar high achiever was plagued by the same doubts and lack of confidence that afflict the rest of us. She wavered between forestry and geology as she was applying for college, she was stymied by organic chemistry as a freshman, and she was told she either wasn’t studying hard enough or wasn’t good enough. At times she felt she didn’t belong, and at other times she was told so. But Elkins-Tanton overcame those obstacles—and others far more profound.

To cover all that ground, Elkins-Tanton braids several different threads into one book.

From Russia with lava

One thread is a fascinating account of her adventures as a geologist, particularly her expeditions to the remotest wilds of Siberia. There, she found herself helicoptering onto the tundra and navigating freezing waters in a pontoon boat held together with duct tape, sharing an aircraft cargo bay with thawing, smelly caribou carcasses, sipping vodka around the campfire in the snow, and eating in clouds of mosquitos so thick that the insects landed in her food as it was en route from her bowl to her mouth. She also recounts even less glamorous aspects of those trips: the occasionally difficult team dynamics, the fruitless quest for zircon crystals, wrangling Russian permits, and a scary escape from an alcohol-addled local.

Over several years, these expeditions netted 850 pounds of samples that led to a slew of papers from a multi-institution, multi-nation group of researchers. These conclusively tied the Siberian flood basalts to the end-Permian mass extinction, a key result for both biology and geology.

She also describes her early research building high-pressure furnaces to melt rock powder. She casually mentions how her arc welder used to shock her via her eye socket. These furnaces would run for six months at a time, occasionally breaking with “bangs like gunfire.” After almost a year of building and running the experiment, her samples hadn’t melted, so she simply began again at an even higher temperature and pressure.

Manifesto

Another thread in the book amounts to a manifesto rejecting the traditional ways of teaching science and math as being “like trying to train dogs by using electric collars,” where progress is an ordeal of tests and grades. “There’s a myth that the people with high academic research achievement got there through an inherent disciplinary genius or a drive from childhood,” writes Elkins-Tanton.

Her approach favors asking questions, finding the answers through research, and synthesizing the results, which doesn’t normally happen until the postgraduate level. These ideas led her to co-found Beagle Learning, an education platform, and to patent a system of inquiry-driven learning.

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