Low explosives deflagrate

Thursday, August 31st, 2017

High explosive detonate, while low explosives deflagrate:

Low explosives are compounds where the rate of decomposition proceeds through the material at less than the speed of sound. The decomposition is propagated by a flame front (deflagration) which travels much more slowly through the explosive material than a shock wave of a high explosive. Under normal conditions, low explosives undergo deflagration at rates that vary from a few centimetres per second to approximately 400 metres per second.

[...]

Low explosives are normally employed as propellants. Included in this group are petroleum products such as propane and gasoline, gunpowder (both black and smokeless), and light pyrotechnics, such as flares and fireworks.

[...]

High explosives (HE) are explosive materials that detonate, meaning that the explosive shock front passes through the material at a supersonic speed. High explosives detonate with explosive velocity ranging from 3 to 9 km/s. For instance, TNT has a detonation (burn) rate of approximately 5.8 km/s (19,000 feet per second),

Detonation has an interesting etymology:

Detonation (from Latin detonare, meaning “to thunder down”) is a type of combustion involving a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it.

[...]

In classical Latin, detonare means “to stop thundering”, as in weather. The modern meaning developed later.

Posted in Linguistics, Science, Weapons | 2 Comments »

US Army creates powder that recharges equipment in the field

Wednesday, August 30th, 2017

The US Army Research Laboratory has created an aluminum-based powder that produces a surprisingly high amount of energy when placed in water:

The unexpected discovery came when researchers mixed a nanogalvanic aluminum-based powder with water, and noticed that the water began bubbling away. On closer inspection, they soon realized the reaction was the product of hydrolysis, meaning the material was splitting the water into its composite molecules of oxygen and hydrogen.

Aluminum has been known to produce hydrogen in this manner, but it usually requires a catalyst in the form of heat, acid, electricity or other chemicals. But the new nanomaterial turns out to be an efficient mechanism for rapid and spontaneous hydrolysis of water.

“In our case, it does not need a catalyst,” says Anit Giri, a physicist on the team. “Also, it is very fast. For example, we have calculated that one kilogram (2.2 lb) of aluminum powder can produce 220 kilowatts of power in just three minutes. That’s a lot of power to run any electrical equipment. These rates are the fastest known without using catalysts such as an acid, base or elevated temperatures.”

For these initial tests, the team used the hydrogen created through the reaction to power a radio-controlled model tank around the lab. But in future, the team says the material’s energy potential can effectively be doubled if the heat given off is also harnessed.

“There are other researchers who have been searching their whole lives and their optimized product takes many hours to achieve, say 50 percent efficiency,” says Scott Grendahl, team leader on the project. “Ours does it to nearly 100 percent efficiency in less than three minutes.”

Posted in Technology | 11 Comments »

Just 2 Seconds

Tuesday, August 29th, 2017

Gavin de Becker’s Just 2 Seconds looks at assassinations — “attacks, near attacks, and incidents against at-risk persons all over the world from 1960-2007″ — and includes an appendix for bodyguards to provide their clients:

Just 2 Seconds Appendix 1.1

Just 2 Seconds Appendix 1.2

Just 2 Seconds Appendix 1.3

Just 2 Seconds Appendix 1.4

Posted in Crime, War | No Comments »

Never stop learning like a child

Monday, August 28th, 2017

The idea that the mind fossilises as it ages is culturally entrenched:

One study by Yang Zhang at the University of Minnesota in Minneapolis that focused on the acquisition of foreign accents in adults suggests we may simply be suffering from poor tuition. When the researchers gave them recordings that mimicked the exaggerated baby talk of cooing mothers, the adult learners progressed rapidly.

Nor do adults necessarily fumble over the intricate movements that are crucial for music or sport. When volunteers visiting Virginia Penhune’s lab at Concordia University in Montreal, Canada, learned to press keys in a certain sequence, at certain times — essentially a boiled-down version of keyboard practice — the adults tended to outshine the younger volunteers.

During a more challenging test of hand-eye coordination, nearly 1000 volunteers of all age groups learned to juggle over a series of six training sessions. As you might expect, the senior citizens aged 60 to 80 began with some hesitation, but they soon caught up with the 30-year-olds and by the end of the trials all the adults were juggling more confidently than the 5 to 10-year-olds.

Old dogs, then, are much more adaptable than folklore would have it — and if we do have deficits, they aren’t insurmountable. The reason that children appear to be better learners may have more to do with their environment, and factors such as physical fitness (see “Faster body, faster mind”).

Indeed, many researchers believe that an adult’s lifestyle may be the biggest obstacle. “A child’s sole occupation is learning to speak and move around,” says Ed Cooke, a cognitive scientist who has won many memory contests. “If an adult had that kind of time to spend on attentive learning, I’d be very disappointed if they didn’t do a good job.”

A glut of free time and a carefree existence are out of reach for most of us, but there are other behaviours that boost children’s learning, and these habits can be easily integrated into even an adult’s schedule. For example, children are continually quizzed on what they know — and for good reason: countless studies have shown that testing doubles long-term recall, outperforming all other memory tactics. Yet most adults attempting to learn new skills will rely more on self-testing which, let’s be honest, happens less often.

[...]

Adults can hamper progress with their own perfectionism: whereas children throw themselves into tasks, adults often agonise over the mechanics of the movements, trying to conceptualise exactly what is required. This could be one of our biggest downfalls. “Adults think so much more about what they are doing,” says Gabriele Wulf at the University of Nevada, Las Vegas. “Children just copy what they see.”

Wulf’s work over the past decade shows that you should focus on the outcome of your actions rather than the intricacies of the movements. She applies this finding in her own life: as a keen golfer, she has found it is better to think about the swing of the club, for instance, rather than the position of her hands. “I’m always trying to find where best to focus my attention,” she says. Similarly, if you are learning to sing, then you should concentrate on the tone of the voice, rather than on the larynx or the placement of the tongue. Study after study shows that simply shifting your mindset in this way accelerates your learning – perhaps by encouraging the subconscious, automatic movements that mark proficiency.

Misplaced conscientiousness may also lead adults to rely on overly rigid practice regimes that stifle long-term learning. The adult talent for perseverance, it seems, is not always a virtue. Left to their own devices, most people segment their sessions into separate blocks — when learning basketball, for instance, they may work on each shot in turn, perhaps because they feel a desire to master it. The approach may bring rapid improvements at first, but a host of studies have found that the refined technique is soon forgotten.

Instead, you do better to take a carousel approach, quickly rotating through the different skills to be practised without lingering too long on each one. Although the reason is still unclear, it seems that jumping between skills makes your mind work a little harder when applying what you’ve learned, helping you to retain the knowledge in the long term — a finding that has helped people improve in activities ranging from tennis and kayaking to pistol shooting.

Such an approach might not be to everyone’s taste — with intricate skills, it might feel like you are making no progress. But even if you do revert to stints of lengthy practice, you can still reap some of the same benefits by occasionally trying out your skills in an unfamiliar situation. In tennis, you might move to a different part of the court for a couple of serves before returning to the regular position; while playing scales on a musical instrument, you might switch hands temporarily. According to work by Arnaud Boutin at the Leibniz Research Centre for Working Environment and Human Factors in Dortmund, Germany, venturing out of your comfort zone in this way helps to ensure that you improve your overall performance rather than confining your progress to the single task at hand. “Otherwise, the longer you practise, the harder it becomes to transfer the skills that you’ve learned to new situations,” says Boutin.

If none of that helps you learn like a child, simply adopting the arrogance of youth may do no harm. “As we get older, we lose our confidence, and I’m convinced that has a big impact on performance,” says Wulf. To test the assumption, she recently trained a small group of people to pitch a ball. While half were given no encouragement, she offered the others a sham test, rigged to demonstrate that their abilities were above average. They learned to pitch on target with much greater accuracy than those who didn’t get an ego boost.

Posted in Education | 1 Comment »

Bluetooth

Sunday, August 27th, 2017

Bluetooth LogoWhy would anyone name a wireless protocol Bluetooth?

The name “Bluetooth” is an Anglicised version of the Scandinavian Blåtand, the epithet of the tenth-century king Harald Bluetooth, who united dissonant Danish tribes into a single kingdom and, according to legend, introduced Christianity as well.

The idea of this name was proposed in 1997 by Jim Kardach of Intel who developed a system that would allow mobile phones to communicate with computers. At the time of this proposal he was reading Frans G. Bengtsson’s historical novel The Long Ships about Vikings and King Harald Bluetooth. The implication is that Bluetooth does the same with communications protocols, uniting them into one universal standard.

The Bluetooth logo is a bind rune merging the Younger Futhark runes Hagall and Bjarkan, Harald’s initials.

I actually have a copy of Bengtsson’s The Long Ships on my shelf.

Posted in Technology | No Comments »

The Dan Plan failed

Sunday, August 27th, 2017

I first heard about the Dan Plan — in which Dan McLaughlin decided to put aside everything else to put in 10,000 hours of deliberate golf practice and become an adult prodigy — six years ago. It didn’t work out:

Enlisting a coach, McLaughlin collected data on his performance and sent it to Ericsson, who plotted his improvement. McLaughlin built his game from the hole out. For months, all he did was putt. Gradually, he moved farther from the flag, adding clubs. Eighteen months in, he played his first full round. At peak practice, he was putting in four hours on the practice green and driving range and playing 18 holes daily. He was stingy in tallying hours toward the 10,000 mark, only counting concentrated practice.

Barely over halfway through, he’d pared his handicap to an all-time low of 2.6 — a mark achieved by fewer than 6 percent of golfers.

[...]

As he progressed, McLaughlin found that many of our instincts turn out to be self-defeating. “People’s intuitions about practice are nowhere near optimal,” says Robert Bjork, a professor in cognitive psychology at the University of California, Los Angeles, whose research has demonstrated the effectiveness of introducing “deliberate difficulty” into practice — for instance, constant variety, “interleaving” between different skills and “spacing” study to force students to retrieve, and embed, new knowledge between sessions.

“You want to increase arousal so [the brain encodes] information at a deeper level,’” says Mark Guadagnoli, a professor of neuroscience and neurology at the University of Nevada, Las Vegas, School of Medicine. “It’s [like] using a laser to engrave something versus a ballpoint pen.”

With advice from Bjork, Ericsson, Guadagnoli, and others, McLaughlin incorporated these principles. But only after he’d burned months drilling single skills like putting — intuitively the best way to practice, but actually the least effective.

[...]

According to the PGA, for every one of the 245 spots on the PGA Tour, there are 326,000 active golfers worldwide. Bjork got a look at McLaughlin’s game in 2014. “I could watch him and think it was remarkable for someone who hadn’t played before,” Bjork recounts. “Or, I could look at him … and say the whole idea of [making] the pro tour was unrealistic.”

McLaughlin stuck to his task for years, but 6,003 hours in, his back would no longer comply. “I couldn’t swing a club for six months,” he says. Today, he’s fine — as long as he doesn’t try to play golf every day. And the Dan Plan is a digital ruin, trailing off mid-stream amid the plaintive questions of diehard fans: “What’s the latest Dan?”

Posted in Education | 2 Comments »

John Danaher on Mayweather–McGregor

Saturday, August 26th, 2017

John Danaher discusses Mayweather–McGregor:

Tonight is the biggest fight show of the year — a fight that has been dismissed by many knowledgeable pundits as farcical but which has nonetheless garnered more viewer interest than any boxing event in a very long time. On the face of it, this is a huge mismatch. Mr Mayweather is unquestionably the finest boxer of his generation and arguably of all time. He is both a master technician and a master tactician in the ring who has made the best boxers of his time look ordinary when matched with him. Mr McGregor is an an outstanding MMA fighter with an amazing penchant for proving doubters wrong. In truth however, this project would be the equivalent of having Mr McGregor compete in an IBJJF jiu jitsu tournament in a gi against say, Rafa Mendes — do you really think he would prevail against Mr Mendes under these conditions?

My experience of watching very good MMA athletes spar against elite boxers in the gym is always the same — they are quite competitive for the first 3–4 rounds and do surprisingly well. Then around the 5th round the elite boxer begins to figure out the unorthodox or awkward movement and begins to employ ring craft tactics to tire the MMA athlete by making him work harder than he is, making him miss punches etc etc. around the 8th round a very noticeable shift occurs where the elite boxer takes over.

I expect a similar pattern tonight — though probably taking less time, given the incredible skill level of Mr Mayweather. Mr McGregors only advantages are youth and size, but heavier punches are not much use if they are thrown at a target that can’t be hit, and Mr Mayweather is as always, in fine shape and has never tired in a fight. I would consider it a fine victory for Mr McGregor if he survived 12 rounds and had some competitive rounds among them. Like most people, I love to see an underdog take on impossible odds and win, so my heart is with Mr McGregor, but my mind knows this is exceedingly unlikely.

In a world of uncertainty I will offer you one certainty that I truly believe — however well Mr Mcgregor does in tonight’s boxing match, I ASSURE YOU IT WILL BE MUCH BETTER THAN MR MAYWEATHER WOULD DO IN A REAL FIGHT AGAINST MR MCGREGOR.

Posted in Martial Arts | 3 Comments »

They were warriors out of a very organized society

Saturday, August 26th, 2017

Archaeologists uncovered four ancient ring-shaped fortresses in Denmark in the 1930s and only recently discovered another:

Q: How did you discover the fortress?

A: It’s a bit of a detective story. I’ve been working with these ring fortresses for quite some time, and I came to the conclusion that their distribution didn’t make sense. There were gaps in the network of known fortresses where logically another fortress should have been. I went out looking for landscape features that matched those of the fortresses we knew already, namely accessibility to land and water routes. There were only a few locations in Denmark that really fit the pattern. The Danish state has made a high-resolution LIDAR image of the whole country, so we searched that and found this very, very big feature.

Q: How did it go unseen for so long?

A: The agricultural activity around it was extremely destructive. For hundreds of years throughout the Middle Ages, peasants ploughed and leveled the field. When we came, the fortress’s ramparts were less than half a meter above the average level of the field. You could walk the field, and I might have a hard time convincing you there was anything at all, but the LIDAR image was decisive.

Q: Why did Vikings build ring-shaped fortresses?

A: The ring is the perfect shape for a fortress. It’s the shape that encompasses the greatest area within the smallest circumference. But there’s no need to make it a perfect circle, and that’s what distinguishes the Viking Age ring fortresses in Denmark. Clearly the person who built these Viking ring fortresses—and we think that was King Harald “Bluetooth” Gormsson [who united Scandinavia, converted the Danes to Christianity and, more recently, lent his name to Bluetooth wireless technology], whose father was the first ruler of the Danish kingdom—wanted something more. All the fortresses share this strict geometry. Somebody with magnificent land-surveying skills was involved in this building work for no other reason than sheer prestige and to signal command and ability.

Q: Did the they invent the ring-shaped fortress?

A: No, they probably learned it from their own invasions in England. The people there built a network of fortifications about 100 years before our structures as a defense against the Vikings. It worked so well that the invaders could not get a foothold and had to turn back. It was a huge success for the Anglo-Saxon kings. So we believe that when ring fortresses then pop up in Denmark, it’s a copying of that strategy.

Viking Ring Fort Reconstruction

Q: Why are these structures important?

A: These ring fortresses have been the biggest mystery in Viking archaeology since the 1930s. People couldn’t believe the Vikings in their own country built these structures. They thought foreign armies must have built them. But as we found more of these, we found it was indeed a Danish king and his Viking warriors, and for that reason they have been part of the most fundamental reassessment of what the Vikings were all about. They were warriors, obviously, but they were warriors out of a very organized society.

Posted in Science, Technology, War | No Comments »

Endurance sports are dominated by white-collar workers

Friday, August 25th, 2017

Cycling, running, and obstacle course racing are dominated by white-collar workers:

Participating in endurance sports requires two main things: lots of time and money. Time because training, traveling, racing, recovery, and the inevitable hours one spends tinkering with gear accumulate — training just one hour per day, for example, adds up to more than two full weeks over the course of a year. And money because, well, our sports are not cheap: According to the New York Times, the total cost of running a marathon — arguably the least gear-intensive and costly of all endurance sports — can easily be north of $1,600.

No surprise, then, that data collected in 2015 by USA Triathlon shows that the median income for triathletes is $126,000, with about 80 percent either working in white-collar jobs — professions such medicine, law, and accounting — or currently enrolled as students. Running USA surveys conducted in 2015 and 2017 found that nearly 75 percent of runners earn more than $50,000, and about 85 percent work in white-collar, service, or educational settings. A 2013 report published by USA Cycling shows much the same: More than 60 percent of individuals who compete in cycling events claim household incomes above $75,000. And though it doesn’t track employment, the same USA Cycling report shows that 66 percent of cyclists have at least an undergraduate degree.

There are a handful of obvious reasons the vast majority of endurance athletes are employed, educated, and financially secure. As stated, the ability to train and compete demands that one has time, money, access to facilities, and a safe space to practice, says William Bridel, a professor at the University of Calgary who studies the sociocultural aspects of sport. “The cost of equipment, race entry fees, and travel to events works to exclude lower socioeconomic status individuals,” he says, adding that those in a higher socioeconomic bracket tend to have nine-to-five jobs that provide some freedom to, for example, train before or after work or even at at lunch. “Almost all of the non-elite Ironman athletes who I’ve interviewed for my research had what would be considered white-collar jobs and commented on the flexibility this provided,” says Bridel.

Research published in the American Journal of Preventative Medicine found that low-income neighborhoods were 4.5 times less likely to have recreational facilities — like pools, gyms, and tennis courts — than high-income neighborhoods. In some low-income areas, less than 20 percent of residents live within a half-mile of a park or within three miles of a recreational facility. Compare that to the 98 percent of New York County residents and 100 percent of San Francisco County residents who live within walking distance to a park.

This is why poor Kenyans have no chance at marathon success.

The salient point is that the voluntary suffering of endurance sports attracts the Upper Middle Class:

One hypothesis is that endurance sports offer something that most modern-day knowledge economy jobs do not: the chance to pursue a clear and measurable goal with a direct line back to the work they have put in. In his book Shop Class as Soulcraft: An Inquiry into the Value of Work, philosopher Matthew Crawford writes that “despite the proliferation of contrived metrics,” most knowledge economy jobs suffer from “a lack of objective standards.”

Ask a white-collar professional what it means to do a good job at the office, and odds are they’ll need at least a few minutes to explain their answer, accounting for politics, the opinion of their boss, the mood of their client, the role of their team, and a variety of other external factors. Ask someone what it means to do a good job at their next race, however, and the answer becomes much simpler.

[...]

Another reason white-collar workers are flocking to endurance sports has to do with the sheer physicality involved. For a study published in the Journal of Consumer Research this past February, researchers from the Cardiff Business School in Wales set out to understand why people with desk jobs are attracted to grueling athletic events. They interviewed 26 Tough Mudder participants and read online forums dedicated to obstacle course racing. What emerged was a resounding theme: the pursuit of pain.

“By flooding the consciousness with gnawing unpleasantness, pain provides a temporary relief from the burdens of self-awareness,” write the researchers. “When leaving marks and wounds, pain helps consumers create the story of a fulfilled life. In a context of decreased physicality, [obstacle course races] play a major role in selling pain to the saturated selves of knowledge workers, who use pain as a way to simultaneously escape reflexivity and craft their life narrative.” The pursuit of pain has become so common among well-to-do endurance athletes that scientific articles have been written about what researchers are calling “white-collar rhabdomyolysis,” referring to a condition in which extreme exercise causes kidney damage.

“Triathletes who I interviewed for my research talked about how the pain that they experienced during training and racing was one of the primary reasons they did it,” says Bridel. “To overcome this pain and get across the finish line served as a significant form of achievement and demonstrated an ability to discipline their bodies.”

Posted in Fitness | 10 Comments »

They aren’t nestled within the same part of the fungal family tree

Thursday, August 24th, 2017

Many mushrooms are magical, and they’re not all closely related:

Around 200 species [produce psilocybin], but they aren’t nestled within the same part of the fungal family tree. Instead, they’re scattered around it, and each one has close relatives that aren’t hallucinogenic. “You have some little brown mushrooms, little white mushrooms … you even have a lichen,” Slot says. “And you’re talking tens of millions of years of divergence between those groups.”

It’s possible that these mushrooms evolved the ability to make psilocybin independently. It could be that all mushrooms once did so, and most of them have lost that skill. But Slot thought that neither explanation was likely. Instead, he suspected that the genes for making psilocybin had jumped between different species.

These kinds of horizontal gene transfers, where genes shortcut the usual passage from parent to offspring and instead move directly between individuals, are rare in animals, but common among bacteria. They happen in fungi, too. In the last decade, Slot has found a couple of cases where different fungi have exchanged clusters of genes that allow the recipients to produce toxins and assimilate nutrients. Could a similar mobile cluster bestow the ability to make psilocybin?

To find out, Slot’s team first had to discover the genes responsible for making the drug. His student Hannah Reynolds searched for genes that were present in various hallucinogenic mushrooms, but not in their closest non-trippy relatives. A cluster of five of genes fit the bill, and they seem to produce all the enzymes necessary to make psilocybin from its chemical predecessors.

After mapping the presence of these five genes in the fungal family tree, Slot’s team confirmed that they most likely spread by jumping around as a unit. That’s why they’re in the same order relative to each other across the various hallucinogenic mushrooms.

These genes seem to have originated in fungi that specialize in breaking down decaying wood or animal dung. Both materials are rich in hungry insects that compete with fungi, either by eating them directly or by going after the same nutrients. So perhaps, Slot suggests, fungi first evolved psilocybin to drug these competitors.

His idea makes sense. Psilocybin affects us humans because it fits into receptor molecules that typically respond to serotonin — a brain-signaling chemical. Those receptors are ancient ones that insects also share, so it’s likely that psilocybin interferes with their nervous system, too. “We don’t have a way to know the subjective experience of an insect,” says Slot, and it’s hard to say if they trip. But one thing is clear from past experiments: Psilocybin reduces insect appetites.

Posted in Science | No Comments »

Researchers have quantified Muhammad Ali’s mental decline

Thursday, August 24th, 2017

Researchers have quantified Muhammad Ali’s mental decline as he took more punches throughout his career:

In 1968, Ali spoke at a rate of 4.1 syllables per second, which is close to average for healthy adults. By 1971, his rate of speech had fallen to 3.8 syllables per second, and it continued sliding steadily, year by year, fight by fight. An ordinary adult would see little or no decline in his speaking rate between the ages of 25 and 40, but Ali experienced a drop of more than 26% in that same period. Slowing his speaking rate couldn’t indefinitely compensate for the deterioration of signals between his brain and his speech muscles. The paper suggests that by 1978, six years before his Parkinson’s syndrome diagnosis and three years before his retirement from boxing, Ali was slurring his words.

In addition to this overall decline in speech, researchers found a strong relationship between Ali’s activity in the ring and his verbal skills. The more punches he took, the more steeply his speaking abilities declined. (Listen to a sample of Ali’s speech changes.)

In 1977, the 35-year-old Ali fought a brutal, 15-round bout with Earnie Shavers. One of the strongest punchers in boxing history, Shavers hit Ali with 266 punches, including 209 power punches, according to the new CompuBox data. Before his fight with Shavers, Ali spoke at a rate of 3.7 syllables per sec. After the fight, his speaking rate fell 16% to 3.1 syllables per sec. His voice also became less animated in the immediate aftermath of fights.

Posted in Linguistics, Martial Arts, Science | No Comments »

Hitting a bullet with a bullet

Wednesday, August 23rd, 2017

Hitting a bullet with a bullet is far from easy, as the history of ballistic missile defense has demonstrated, but the US had some success in the Gulf War:

The Gulf War story is overwhelmingly one of Coalition military and technological success, with one notable exception: the campaign against Iraqi tactical ballistic missiles. Initially this aspect of the war looked to be a lopsided contest pitting Iraq’s outdated missiles against the Coalition’s overwhelmingly superior technology and complete air dominance. But this is not how events unfolded. Despite using nearly every type aircraft in the Coalition’s considerable air fleet against the Scuds, in the words of one participant and student of this campaign, there was “scant evidence of success.” The Iraqis effectively used their Scuds to frustrate the Coalition, seize the initiative, and to apply great political and psychological pressure that had the potential to unravel the alliance. In this way, the Scud campaign was the high point for the Iraqis and low point for the Coalition airmen.

From the outset the reader should realize that the Gulf War was neither the first nor the largest ballistic missile war. These distinctions belong to the German V-2 missile campaign that rained destruction on Allied cities during World War II. The V-weapons campaign was much larger in numbers and much more destructive, albeit shorter in range, than the Iraqi missile offensive. However both campaigns had similar limitations (poor accuracy and small conventional warheads) and were mainly political and psychological in their intent and impact. Forty-five years separated the two operations, but the severe problems, frustrations, and failures experienced by the Allies while defending against German missiles, despite expending tremendous resources, were similar to those encountered by Coalition airmen during the Gulf War. One major difference between the two campaigns was that in the more recent war is that the defenders had an active ground-based defense.

Scud is the North Atlantic Treaty Organization (NATO) code word for a Soviet surface-to-surface ballistic missile that evolved from the German V-2. It is little improved over the German missile, primarily having a longer range, somewhat better accuracy, but carrying a smaller payload. The Soviets tested the Scud A in April 1953 and deployed it in 1955. Scud B was an improved version that extended the missile’s range from 180km to 300km, and enhanced its accuracy from 4,000 to 1,000 meters CEP but carried only half the 989kg warhead of the “A.” ” It was first launched in 1957. A key feature of this type missile was its mobility, made possible by its wheeled chassis that served as a transporter, erector, and launcher (TEL). In 1961 the Soviets began exporting the Scud A to their Warsaw allies and then in 1973 shipped the first Scud B to Egypt, and later to a number of other middle east countries, including Iraq.

[...]

Casualties were far lower than estimated. The Israelis suffered only two direct deaths from the Scuds, and another eleven indirectly, four from heart attacks and seven 95 suffocating in their gas masks. In addition, probably 12 Saudis were killed and 121 wounded. There were also American casualties. On 26 February a Scud hit a Dhahran warehouse being used as a billet by about 127 American troops, killing 28 and wounding 97 others. This one Scud accounted for 21 percent of the US personnel killed during the Q7 war, and 40 percent of the wounded. A number of factors explain this incident. Apparently one Patriot battery was shut down for maintenance and another had cumulative computer timing problems. Another factor was just plain bad luck. The Scud warhead not only hit the warehouse, but unlike so many others, it remained intact, and detonated. Conversely, one Scud impacted in Al Jubail Harbor about 130 yards from the USS Tarawa and seven other ships moored next to a pier that was heavily laden with 5,000 tons of artillery ammunition. The missile’s warhead did not explode. These are the fortunes of war. Thus, the overall death rate was less than one killed per missile fired.

The Scuds lacked numbers, warhead size, and accuracy to be militarily significant. But General Norman Schwarzkopf’s continued restatement of these facts not only missed the point, it was politically dangerous. The general’s words indicated to the Israelis a lack of America’s concern, and encouraged Israeli counteraction. Scuds had a great psychological and political impact, especially as they were coupled with the threat of poison gas. The Israelis were not about to stand by as Iraqi missiles showered their cities with death and destruction. If they intervened, however, the carefully constructed Coalition could quickly unravel, which, of course, was what the Iraqis intended.100 In sharp contrast to the field commander, the top American leadership, specifically Secretary of Defense Richard Cheney and Joint Chiefs of Staff (JCS) Chairman, General Colin Powell, saw keeping Israel out of the war as the number one priority and the Scuds as the number one problem.

Although the Israelis rejected American aid before the shooting started, the first Scud impact changed everything. The Israelis quickly requested both American Patriot missile assistance and Identification Friend or Foe (IFF) codes to allow their aircraft to strike Iraqi targets without tangling with Coalition aircraft. The US quickly agreed to the first, but refused the second. However, the decision makers realized that the Scud menace had to be contained to keep the Israelis out of the conflict. One important element in this effort was the Army’s Patriot surface-to-air missile (SAM).

[...]

The Army’s Patriot surface-to-air missile formed the last line of active defense against the Scuds. The US was able to airlift 32 Patriot missiles to Israel within 17 hours and get them operational within three days. Patriot deployment to the Gulf eventually consisted of seven batteries to Israel, 21 to Saudi Arabia, and four to Turkey.

Crucial to the active BMD was early warning provided by strategic satellites. Although American Defense Support Program (DSP) satellites were designed to give warning of ICBM launches, they demonstrated the ability to track the lower flying, cooler, short range, tactical ballistic missiles, as demonstrated against hundreds of tactical ballistic missiles during their tests and in two Mid-Eastern wars.111 Before the shooting started in the Gulf War, two young captains at Strategic Air Command (SAC), John Rittinghouse and J.D. Broyles, worked out a system that coordinated information from the satellites, routed it through three widely located headquarters (SAC, Space Command, and Central Command), and passed it along to the user in the field. While the satellite did not precisely indicate either the location of launch or anticipated point of impact, it did give general information. The bottleneck was the communications, nevertheless, the juryrigged system gave a few minutes’ warning to both the defending Patriot crews and people in the target area. During the war, the satellites detected all 88 launches.

One of the main controversies of the war centered on the effectiveness of the Patriot against the Scud, or more precisely, how many Patriots hit Scuds. Of the 88 Scuds launched, 53 flew within the area of Patriot coverage. The defenders engaged most of these, 46 to 52 according to secondary accounts, with 158 Patriot missiles. Schwarzkopf initially claimed 100 percent Patriot success. After the war the manufacturer boasted of 89 percent success over Saudi Arabia and 44 percent over Israel, then in December 1991 the Army asserted 80 percent and 50 percent success, respectively. The next April the official success claims were further reduced to 70 and 40 percent in the two areas.

[...]

This misses the main point: regardless of the exact interception figures, Patriots proved very effective. Just as the Scuds were primarily a psychological weapon, so too were the Patriots. They provided great theater, with live videos of fiery launches, smoke trails, and aerial fireworks made more vivid with a dark, night background that had a positive impact on civilians and decision makers in the US, Saudi Arabia, and Israel. (There is no indication that any Iraqis saw this very visible performance, and if so, what impact it had on them.) The situation was manageable for the defenders as long as the Scud attacks were limited in number, inaccurate, and killed few people. Missile warning protected civilians from death and injury, while active missile defenses bolstered morale. The Patriots were an important factor in keeping Israel out of the war.

Posted in Technology, War, Weapons | 3 Comments »

Eating raw marine mammals isn’t the same as eating cooked land mammals

Tuesday, August 22nd, 2017

A couple decades ago, when I first became interested in evolutionary fitness and ketogenic diets, I read that the Eskimos had traditionally lived on a diet almost entirely bereft of carbohydrates — a diet that Vilhjalmur Stefansson tried to promote amongst non-Eskimos in magazine articles and then in his 1946 book, Not by Bread Alone.

Traditional Inuit Diet

But Stefansson Westernized the Inuit diet of raw marine mammals and instead promoted a cooked, all-animal-food-diet, including dairy and eggs — a difference that matters once you realize how marine mammals have adapted to diving and operating with limited air:

Stefansson — who died of a stroke at 82 (though, surprisingly, he lived longer than a lot of other VLC authors) — made the fatal assumption that land mammals and marine mammals are similar. They aren’t. They are entirely different, and the difference is tantamount to different species classification. The Inuit were exploiting unique carbohydrate properties in these marine mammals that aren’t found in land mammals.

It turns out that marine mammals that spend a good deal of their time diving to great depths have significant glycogen stores. Sperm whales make routine dives to 400 meters for 40 minutes and can reach a maximum depth of 2000 meters (6,560 feet, or 1.25 miles). Narwhals make some of the deepest dives recorded for a marine mammal, diving to at least 800 meters (2,600 feet) 18 and 25 times per day every day for 6 months, with many dives reaching 1,500 meters (4,900 feet). Narwhals have been recorded diving to as deep as 1,800 meters (5,900 ft, over one mile). In addition to making remarkably deep dives, narwhals also spend more than 3 hours per day below 800 meters — this is an incredible amount of time at a depth where the pressure can exceed 2200 PSI (150 atmospheres).

During their deep dives these marine mammals run out of oxygen and switch to their unique glycogen-based energy stores. They store large quantities of glycogen in very odd places, but it typically gets concentrated in the skin and organs. Researchers have discovered significant “glycogen pools” in the narwhal’s arterial thoracic retia. Ringed seals have “large quantities of glycogen” in a gelatinous material near their sinuses. A sperm whale’s blubber ranges from 8–30% carbohydrates, mostly believed to be glycogen. The hearts and brains of weddel seals have concentrations of glycogen that are two to three times that of land mammals. Furthermore; in marine mammals, these organs tend to be larger in proportion to the total body weight than in land-based mammals.

In 1973, George and Ronald wrote about the harp seal, “All the fiber types contained considerable amounts of glycogen…it is postulated that the seal muscle is basically geared for anaerobic use of carbohydrate as an adaptation for the animal’s diving habit.”

In a paper on diving marine mammals Hochachka and Storey wrote, in 1975, “In the terminal stages of prolonged diving, however, even these organs must tolerate anoxia for surprisingly long times, and they typically store unusually large amounts of glycogen for this purpose.”

Perhaps what’s most disappointing is that Stefansson never bothered to clearly explain the Inuit’s favorite sweet-tasting whale skin dish (muktuk), that was already known by scientists to be a carbohydrate-rich food. In 1912, the Journal of the American Medical Association (JAMA) had reported, “the skin [of the narwhal] contains a remarkable amount of glycogen, thus supplying sufficient quantities of a carbohydrate to cure the scorbutus. The walrus liver also contains much glycogen.”

So, this idea that we can compare glycogen content of a [grilled, braised, stewed, or otherwise thoroughly cooked, long after dead] cow or human to that of what the Inuit were eating is entirely misguided. We’re talking about marine animals that need large quantities of glycogen to complete their extended deep dives.

It’s well known that glycogen does not survive very long post-mortem. So, it was no coincidence that the Inuit often consumed glycogen-rich foods quickly and froze whatever they couldn’t consume. Peter Freuchen, a Danish doctor and member of the 5th Thule expedition based at Melville Peninsula from 1919-1925, wrote that when a whale was brought to the beach at Repulse Bay everyone feasted on large quantities of the skin until their jaws became too sore to continue.

After a hunt, seals are quickly cut to expose the internal organs. Kristen Borré writes in her 1991 report for the Medical Anthropology Quarterly, that “one of the hunters slits the abdomen laterally, exposing the internal organs. Hunters first eat pieces of liver or they use a tea cup to gather some blood to drink.” This was no coincidence. The parts of the animals with the most glycogen were eaten quickly.

At the time of death, the glycogen and free glucose in beef muscle contains approximately 6g of glucose equivalents per pound. As explained above, diving marine mammals have much more glycogen than land mammals. When we consider that the average Inuit consumed 5 to 10 pounds, or more, of raw fresh or flash-frozen meat per day, it should be clear that they were consuming a lot of glycogen.

But, of course, the Inuit consumed other carbs, too. They consumed berries, seaweed, nuts, corms, and tubers — such as yupik potatoes, boiled polysaccharide-rich seaweed, glycogen-rich winter mussels. See the Disrupting Paleo series for a more indepth discussion of these foods and their importance in the Inuit diet.

What about the glycogen in the foods that weren’t consumed rapidly? If only the Eskimos had access to extremely cold temperatures where they could rapidly freeze chunks of meats immediately after hunting… Hmmm… Kidding aside, the Inuit not only consumed fresh raw meat, blubber and skin that was rich in glycogen, but they also consumed it flash frozen — thus preserving and maximizing its glycogen.

Interestingly, Clarence Birdseye — who invented technology for “flash freezing” — learned about it from the Inuit. According to Wikipedia, “He was taught by the Inuit how to ice fish under very thick ice. In -40°C weather, he discovered that the fish he caught froze almost instantly, and, when thawed, tasted fresh.” He recognized immediately that the frozen seafood sold in New York was of lower quality than the frozen fish of Labrador, and saw that applying this knowledge would be lucrative.

While listening to the audio version of Endurance, about Shackleton’s failed attempt to cross the last uncharted continent on foot, I noted that the famished explorers found penguin liver surprisingly delicious.

Posted in Fitness, Science | 6 Comments »

Greeks are close to Jews, and Lebanese are far from Arabs

Monday, August 21st, 2017

Nassim Nicholas Taleb and Pierre Zalloua share some recent genetic discoveries that neither Antisemitic Nordic Supremacists nor Arab Nationalists will like:

1) Greeks were close to Jews, as the “Aryan” theory is genetically bogus & 2) Lebanese (both Christian and Moslem) are very far from being Arabs (the historical accounts of Arab migrations to Lebanon are fiction).

Posted in Policy, Science | 4 Comments »

The most formidable of twenty-first century weapons

Monday, August 21st, 2017

A new study from RAND examines Israel’s Operation Cast Lead in 2009 and Operation Protective Edge in 2014 and shares some lessons learned in Gaza:

For starters, smart weapons are no panacea. The Israel Defense Forces (IDF) attempted to destroy Hamas rocket launchers and tunnels with airpower alone (surprising in light of the failure of such an approach in the 2006 Lebanon War). Lack of success meant ground troops had to be sent in.

The failure of airpower meant the revival of artillery. The IDF barely used artillery in 2009, but used lots of big guns in 2014. “On a technical and tactical level, the IDF’s use of artillery support was impressive,” RAND noted. “It increased its use of precision artillery from earlier campaigns and reduced the minimum safe distances for providing fire support. Artillery fire often proved quicker and more responsive than other means of firepower, such as CAS [close air support].”

Armor also proved its worth in Gaza. “Before Protective Edge, the IDF invested in intelligence and airpower, often at the expense of particularly heavy armor,” RAND found. Or as Israeli sources told RAND, “Half a year before, they closed the Namer [a tank converted into a troop carrier] and we said it was a mistake; and immediately after, they reopened the project. You need protection. Mobility is protection.”

In turn, armor needs active protection systems. “there was near-universal consensus among IDF officers and outside analysts interviewed for this report that vehicles equipped with the Trophy system stood a better chance of surviving not only RPG fire, but also the Kornet ATGM [anti-tank guided missile],” RAND found. “Indeed, according to some accounts, there were at least 15 instances of active protection systems intercepting Kornet-style missiles.” Another unexpected benefit was that the sensors on the Trophy also proved useful in detecting the location of hostile fire.

However, neither smart weapons nor artillery can stop that most formidable of twenty-first century weapons: lawfare, or the use of international law and public opinion to stymie an adversary’s superior firepower. Under intense media scrutiny, the IDF grappled with how to destroy rocket launchers that Hamas had emplaced in densely populated civilian areas. To its credit, Israel tried a variety of means to avoid civilian casualties, including calling residents on their phones to evacuate, social media and the memorable “door knocker” inert bombs landing on roofs as a signal to get out of the target zone. Lawyers even reviewed targeting decisions, and yet Israeli still suffered a public relations disaster, including public and UN accusations of war crimes. Now the IDF General Staff is adding a lawfare section. “For better or worse, lawfare is here to stay, and the IDF — like all Western militaries — will have to wrestle with its implications in any future operation,” RAND concludes.

Posted in Policy, War, Weapons | 6 Comments »

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