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3D-Printed Gun Earns Man Two Years In Japanese Prison

FatLittleMonkey Re:You can Detect 3D Printed Gun (190 comments)

an answer to the growing threat posed by plastic firearms

It stops people being hysterical and stupid about non-issues?

5 hours ago
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A Look At Orion's Launch Abort System

FatLittleMonkey Re:Fuck The Amazon Blue Turd (36 comments)

And yet Boeing is having to hire Blue Turd to develop their next family of large rocket engines for the USAF.

It seems that the much vaunted "experienced" players don't know how to build new rocket engines any more, whereas the non-show vanity project has actually designed and built new generation rocket engines within living memory. (LM is even worse, they have to use surplus Russian engines.) Meanwhile, the first SLS launches will reuse the 25yr old engines off the retired shuttle orbiters; not "engines of the same design", the actual engines pulled off the last three orbiters, burning them up on the first two flights (2017, 2021. No further launches are funded.)

Orion is a poor design, with no mission. The mission it was design for (lunar orbit) is no longer the national goal, and it's completely unsuited to the mission that is the national goal (BEO). It's over-weight, over-priced, and behind schedule.

SLS is a terrible design with no mission beyond its own existence, and is just appallingly overpriced. Boeing is receiving $2.8b for the first two SLS first-stages, in spite of them just being extended shuttle ET's with those recycled SSMEs attached. That's in addition to prior funding Boeing received for designs, reviews, production changes, etc. Just the unit cost. $1.4b each. For just the first stage. This is when NASA projected the SLS launch costs would be $650m per unit for the whole system, including integration and launch ops.

6 hours ago
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A Look At Orion's Launch Abort System

FatLittleMonkey Re:Would this kind of system have saved Challenger (36 comments)

This came up with Orion in the Ares I design. When solids are breached — either intentionally by range-safety or on-board abort systems, or due to the failure itself — they release a cloud of burning solid fuel debris. With a breach of liquid fuel tanks, such as the shuttle ET, you do get that big pretty fireball, but the actual heat being produced is fairly trivial; so as long as you are beyond the over-pressure wave, you are golden. Burning solid fuel is hot particles, when you pass back through the debris cloud, at the very least your parachute will melt and possibly the capsule itself will be damaged.

(At a more human scale, it's like the difference between getting that whumph of gas fireball from starting your gas griller, versus getting sprayed with burning oil. Accept that solid rocket fuel is more like thermite.)

In order to get far enough away from the solid rocket debris cloud, you need a monster LAS with monster acceleration. That results in a LAS as heavy as the capsule itself. And since Orion is already an over-size, over-weight capsule...

6 hours ago
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Favorite clickbait hook?

FatLittleMonkey Re:Is Slashdot now fucking Facebook? (190 comments)

Nothing to do with ads, or Facebook. "Clickbait" refers to the teaser headlines for articles/posts. Same thing you see on the covers of women's magazines, or used by TV news to keep people watching, where the key information is deliberately hidden. On internet sites, it's often taken to a meme-worthy extreme, where even the basic topic is hidden.

It used to be "What Jen's recipe for a great body?", "The secret your doctor doesn't want you to know!" and "Coming up, a story no concerned parent can afford to miss!"

Now it's "This one weird trick will change your life!", "You'll never believe what this woman does!", "You won't be able to stop watching this video!".

It works because SQUIRREL

3 days ago
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Favorite clickbait hook?

FatLittleMonkey Re:Click Here (190 comments)

No need to be embarrassed. That's a more common problem that you realise.

3 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Power Source (348 comments)

I wonder what the trade is like between acres of cooling vanes vs. acres of solar panels. I guess it would depend on the efficiency of both.

In space, in a vacuum, studies apparently have shown that solar wins for the inner solar system. (And that's solar panels winning just compared to the reactor mass. Adding the radiator issue makes them win further out.)

On Mars, solar probably wins in terms of pure power/mass ratio, but solar requires storage for night power (so nearly double the panel area, plus the mass of the battery system) and extra power for heating (which the reactor gives you for free.) And in winter, the numbers get worse.

Same for the moon, except near the poles. With 24hr (or close to it) sunlight, solar wins. Anywhere else, nukes rule.

Mars's atmosphere is thin, but the temperature is very cold... seems like there ought to be a way to take advantage of that.

I was being dismissive: in reality a small reactor suitable for a base wouldn't need much cooling on Mars; after all, we're not talking gigawatt scale plants. So a small set of radiators — sticking up vertically, angled perpendicular to the path of the summer sun — would be plenty. But even that may nor be necessary, you'd use the waste heat for heating the base itself, then the lower grade heat for a greenhouse. At that point, the surface area is probably great enough for the atmosphere to carry the heat away without any special radiators.

[That atmosphere on Mars is annoying. It's too thin to be useful, but thick enough to get in the way. So it can carry enough heat away to make solar heating barely enough to keep greenhouses warm during the day, and at night (and in winter) you'd need loads of extra heating. Mars makes it hard to put up a freakin' greenhouse. And people want to live there.]

3 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Power Source (348 comments)

OTOH, on Mars you've got an atmosphere,

Barely.

so this wouldn't be a problem anyway.

Even on Earth we have cooling towers.

But eventually large-scale power will be needed in the outer solar system. I suppose by then we'll have figured out fusion or something like that.

At the very least, we'll have a better idea what our real needs are. Right now we're like Christopher Columbus trying to design the NY subway system.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Replace rockets with something reasonable. (348 comments)

The space shuttle was a 100+ ton space-plane launched on a Saturn V class launcher. Built without any real precursors, from 1970s technology. Every aspect of it pushed the technology beyond the state-of-the-art. No part of it was built to reduce operating costs. The original proposal sold to Nixon may have been to develop a low cost "space truck", but that was never part of the actual program development goals.

OTOH, Falcon 9 was intended solely to be cheap. And is already the cheapest launcher on the market as an expendable. Even partial reusability (first stage) is expected to lower launch costs significantly. Musk claims that launch operations costs are a small part of his launch costs, and even that will probably drop once his team controls their own site and range.

This gets back to moving away from the "standing army" model of spaceflight operations.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Power Source (348 comments)

Very large radiators.

And the radiators must be protected behind a heavy shield, because the radiation degrades them too quickly. Most designs have the reactor, then a heavy shield, a long truss and then the rest of the ship. Running down the length of the truss, carefully shaped to remain in the shadow of the shield, you have huge radiators to dump the heat from the reactor. The truss, the radiators and the shield are all additional mass required for a nuclear propulsion on top of the reactor mass. Solar arrays require radiators too, but only a fraction of the size, see the ISS.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Robots First, then Humans? (348 comments)

In a way they did. They sent expendable seamen and some Italian loudmouth on a few small off-the-shelf commercial ships. Only when the destination was proven did they risk their more valuable people on more valuable ships.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Robots First, then Humans? (348 comments)

the robots send us a message that says "Everything is ready. We are waiting to meet you all for dinner."

Ummm...

Anyone see a problem with this?

...yeah...

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Hey, idiots (348 comments)

where all the people and things are?

That's the problem. You can't experiment where people live, or where there are things you care about.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Get real (348 comments)

that only puts a few hundred to at most a thousand-plus kg of payload on the moon per flight.

You're doing it wrong. With reusable launchers you want to split your payloads into cargo and fuel, launched separately. Most products have a U or J shaped reliability curve. Higher failure rate at the beginning, picking up manufacturing defects, then lower failure rate until end-of-life effects start to accumulate. Because fuel is cheap, you put that on the brand new, untested reusable launchers, and on the end-of-life launchers and fly them until they die. Because cargo is generally not cheap, you use the in-between launchers, at their peak reliability.

You put your cargo and TLI-engines into LEO on the most reliable launchers using the payload full capacity of your launcher, then you add fuel tanks and associated plumbing on the less reliable launchers, finally you launch bulk propellant on the lowest reliability launchers. Then you launch these large payloads from LEO. You lose some Oberth efficiencies, but you gain in using your launcher's maximum lifespan, and being able to launch larger individual payloads (in the 10-12 tonne range for F9, 50 tonne range for FH, and 250 tonne range for the Raptor-based MCT.)

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Power Source (348 comments)

No form of currently-achievable propulsion yields a higher Isp than a fission fragment rocket

We're so far from FFR, we might as well talk about fusion drives, or Harold White's warp drive.

and a few other space options (such as a nuclear VASIMR-like mode)

My previous comments apply to NEP vs SEP. SEP has better power/mass ratios until you are somewhere near Jupiter, and realistically probably somewhere past Jupiter.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Begin planning use of Lockheed's fusion power (348 comments)

... using NASA designs as the foundation.

I've never understood this argument. By definition, you are saying that everything that is available to these private players was already available to NASA and its primary contractors.

So why is that a justification for minimising the achievements of the new guys? "Yeah, we could have done that. We didn't, but we totally could have." No, no you couldn't. You had decades to do it, your whole job was to do it, you had billions in funding to do it, your primary contractors are orders of magnitude larger than the new players, and yet you didn't do it.

Worse. Even after the new guys did it, you still aren't doing it.

For example, Boeing is getting a multi-billion dollar USAF contract to develop a new large methane engine. They got the contract because of their "decades of experience". Aaaand... they are sub-contracting the actual work to Blue Origin, a dot-com billionaire's tiny little hobby-project which has spent the last decade actually building new rocket engines. But hey, it's the new guys who are leaching off the old players. Sure.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Replace rockets with something reasonable. (348 comments)

Most things can be broken down into sub-100 tonne parts. The problem is not the launch, at least once we stop throwing away our rockets, it's the cost of on-orbit operations. That requires a change in how we work. Ending the standing armies on the ground to support every spanner-turn in space.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

FatLittleMonkey Re:Power Source (348 comments)

Trade studies have suggested that out to the main asteroid belt, aerospace grade solar panels have a higher power/mass ratio than nuclear systems. Only out near Jupiter does the equation shift (but even that is only counting the direct reactor mass. The added mass of shielding, trusses for distance, etc, is usually not included.) And every year, the cross-over distance shifts further out.

The exception is where sunlight is unavailable — Lunar night, Mars winter — where the length of darkness exceeds likely storage capacity. However, the most likely location for early development on the moon is the poles, where there are Peaks of Eternal Light. (How can you not capitalise that?) OTOH, for Mars, you are probably going to avoid the poles due to the severity of those winters, staying within 30 deg of the equator, avoiding that problem too.

So it'll be a fair while before we need nukes, better to focus available funding on something else.

4 days ago
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When will the first successful manned Mars mission happen?

FatLittleMonkey Re:crashing oil tankers (217 comments)

Whatever you manage to throw at the Earth will burn in the atmosphere.

Solid metal will pass through virtually unchanged. Shaped for minimum-drag in hypersonic entry (unlike capsules, which are shaped for braking), it will, by coincidence, be virtually undetectable by radar or optical until it hits the atmosphere. (Unless they are watching activity at the launch site, of course. Which they would be, if they aren't stupid.)

No-one saw the 10,000 tonne, 20m diameter Chelyabinsk meteor, which produced a half-megaton detonation. It was a stony-type meteor, hence it didn't penetrate below 25km. A solid metal manufactured impactor could easily reach the ground; but the optimum shape for a city killer would detonate in the air above the target, but below 5km.

If we see it coming we'll nuke you, even with barely modified 1950s tech.

To reach the moon with even a small nuclear warhead, you would need a full multi-stage rocket launch, not a little ICBM squirted out of a sub or silo. You couldn't hide such a launch. And it would be trackable for the entire 3 day transit to the moon. The lunar loony would just need to launch a load of gravel back along the same trajectory. No more warhead. He then throws some impactors at the launching nation's small number of suitable launch sites. No more counter-attacks. He can also hit a few LEO satellites to start a Kessler cascade, preventing any launches from Earth for several decades. His own impactors (being purely bulk-kinetic) aren't affected as they pass through.

The moon has "air superiority" over Earth due to orbital mechanics. It takes a lot more energy to bomb the moon than it does to bomb Earth. Therefore attacks from Earth must be much larger, and require substantially more infrastructure to launch, which is vulnerable to attack from moon-thrown spears-of-death. (The moon's disadvantage is that it takes a lot of infrastructure to get to that point.)

5 days ago
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Independent Researchers Test Rossi's Alleged Cold Fusion Device For 32 Days

FatLittleMonkey Re:Not so much, maybe. (973 comments)

I think you replied to the wrong comment.

about a week ago

Submissions

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Fight you own muscles to create force-feedback on smartphones

FatLittleMonkey FatLittleMonkey writes  |  about a year and a half ago

FatLittleMonkey (1341387) writes "Researchers in Germany have developed a device that allows users of portable devices, such as smartphones, experience force-feedback from games using just their own muscles... and a small EMS device. When stimulated by a painless electric pulse, the player's arm moves the device in whichever direction the game commands. The player then fights the movement with their other muscles, creating a strong sensation that the device itself is bucking in their hands. According to the developers, users found the sensation much more realistic than traditional vibrotactile feedback. (Should make PvP more interesting too.)"
Link to Original Source
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Multiple minds smooths your ship's path

FatLittleMonkey FatLittleMonkey writes  |  about a year and a half ago

FatLittleMonkey (1341387) writes "My mind to your mind... my thoughts to your thoughts... Researchers at the University of Essex have shown that combining the output from two non-invasive "brain-computer interfaces", computer-interpreted EEG signals, led to a much clearer signal of the subjects' intention than the output from a single subject. To test this idea, they had two subjects try to steer a simulated space-ship at a target planet, by thinking of one of eight possible directions. While a single user could achieve 67% accuracy, this jumped to 90% when two minds were combined. Researchers believe the technique also compensates for individual lapses in attention, and thus may have applications in real-world space missions."
Link to Original Source
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How do you give a ticket to a driverless car?

FatLittleMonkey FatLittleMonkey writes  |  about 2 years ago

FatLittleMonkey (1341387) writes "New Scientist asks a Bryant Walker Smith, from the Center for Internet and Society at Stanford Law School, whether the law is able to keep up with recent advances in automated vehicles. Even states which have allowed self-driving cars require the vehicles to have a "driver", who is nominally in control and who must comply with the same restrictions as any driver such as not being drunk. What's the point of having a robot car if it can't drive you home from the pub while you go to sleep in the back?"
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Whitehouse Petition to sell Texas to pay off US Debt.

FatLittleMonkey FatLittleMonkey writes  |  about 2 years ago

FatLittleMonkey (1341387) writes "Amidst the flood of petitions on behalf of States demanding to be allowed to secede from the US, inevitably came the trolls suggesting that the US at least make some money out of the deal. Sell Texas to Mexico and use the money to pay down the US debt. Still in single digits at time of writing, but well worth supporting for the lulz."
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You can't print a gun if you have no 3d printer

FatLittleMonkey FatLittleMonkey writes  |  about 2 years ago

FatLittleMonkey (1341387) writes "You may recall Cody Wilson's project to create a 3d printed gun, mentioned previously on Slashdot. Well, the Defense Distributed project has suffered a decidedly non-technical setback, with printer manufacturer Stratasys revoking the lease and repossessing the printer (presumably prying it from plastic models of Cory's cold dead hands.) According to New Scientist the manufacturer cited...

his lack of a federal firearms manufacturer's licence as their reason for the repossession, adding that it does not knowingly allow its printers to be used for illegal purposes.

"

Link to Original Source
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If U R readng ths, I M already dead.

FatLittleMonkey FatLittleMonkey writes  |  more than 2 years ago

FatLittleMonkey (1341387) writes "A particularly nasty text scam is doing the rounds in Australia. Police say that hundreds of people have reported receiving text messages reading: "Sum1 paid me to kill you. Get spared, 48hrs to pay $5000. If you inform the police or anybody, death is promised... Email me now killerking999@yahoo.com", or variations on the theme. The Australian Competition & Consumer Commission's Scamwatch site, also details the threat messages.

(No reports yet of anyone managing to troll the scammers.)"

Link to Original Source
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MS damage washed away by stream of young blood

FatLittleMonkey FatLittleMonkey writes  |  more than 2 years ago

FatLittleMonkey (1341387) writes "A new study on mice suggests that damage caused by diseases like Multiple sclerosis, as well as natural ageing, can be reversed by an infusion of stem cell rich blood from younger mice. Multiple sclerosis is a chronic inflammatory disease that erodes the fatty myelin sheaths around the axons of the brain and spinal cord, and can result is serious disability. Similar effects occur naturally with ageing. Via New Scientist:

White blood cells called macrophages from the young mice gathered at the sites of myelin damage. Macrophages engulf and destroy pathogens and debris, including destroyed myelin. "We know this debris inhibits regeneration, so clearing it up is important," says team member Amy Wagers of Harvard University.

Here's a direct Link to the paper, if you have academic access through the paywall.."
Link to Original Source

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Harnessing the energy of Galloping Gertie

FatLittleMonkey FatLittleMonkey writes  |  more than 3 years ago

FatLittleMonkey (1341387) writes "You've all seen the footage of Galloping Gertie, the infamous Tacoma Narrows bridge. This is due to a type of turbulence called Wake Galloping, caused by airflow creating lift on the lee-side of cylinders (or cables on suspension bridges.) Now researchers in South Korea have developed a way of harnessing the turbulence to generate electricity. Their device works most efficiently at wind speeds too low for conventional wind turbines."
Link to Original Source
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Multicellular life found at 3.6km under the crust

FatLittleMonkey FatLittleMonkey writes  |  more than 3 years ago

FatLittleMonkey (1341387) writes "Researchers from Princeton University have discovered nematodes at depth of up to 3.6km in three gold mines in South Africa, likely feeding on the radiation-consuming bacteria also discovered by the same team. Carbon dating their environment confirms that the 500 micrometres long critters have been there for at least 3000 years and are not a recent contaminant. The finding means that unexpectedly complex ecosystems occur deep underground, increasing the chance that complex life may have survived on Mars according to Carl Pilcher, director of NASA's Astrobiology Institute, "The significance was that you could imagine an ecosystem existing in the subsurface of a planet that didn't have a photosynthetic biosphere, like Mars," he says.

Until now, it was thought such an ecosystem could be made of bacteria only. But Onstott's new findings have completely changed that. "These nematodes are grazing on microbes. So now you could imagine that if animal life had ever developed on a planet, and the surface of that planet became lifeless," Pilcher explains, "you could imagine that animals could coexist with microbial ecosystems all powered by radioactivity."

"

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Can computers be used to optimise the US tax code?

FatLittleMonkey FatLittleMonkey writes  |  more than 3 years ago

FatLittleMonkey (1341387) writes "Science Fiction author, David Brin, wonders whether the US tax code, described by President Obama as a "10,000-page monstrosity", could be dramatically simplified. No, he's not trying to get support a libertarian wet-dream "Flat Tax", this is about using computers to... shuffle the existing system.

"I know a simple way the sheer bulk of the tax code could be trimmed by perhaps 70% or more, without much political pain or obstructionism! ... it should be easy to create a program that will take the tax code and experiment with zeroing-out dozens, hundreds of provisions while sliding others upward and then showing how these simplifications would affect, say, one-hundred representative types of taxpayers ... Let the program find the simplest version of a refined tax code that leaves all 100 taxpayer clades unhurt. If one group loses a favorite tax dodge, the system would seek a rebalancing of others to compensate. No mere human being could accomplish this, but I have been assured that a computer could do this in a snap."

With all the talk about Open Government, perhaps the computer code currently used in tax modelling could be released to the wider community, leading eventually to a Folding@Home type project."

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Can't get enough Will & Kate? Now meet their k

FatLittleMonkey FatLittleMonkey writes  |  more than 3 years ago

FatLittleMonkey (1341387) writes "Prince William and Kate Middleton met while attending the University of St Andrews, so it seems... appropriate... that the Perception Lab at St Andrews would have a go at predicting the appearance of the royal couple's future "heir and a spare".

New Scientist also tries its hand at some evolution-centric royal fan-fic.

Oh, and feel free to participate in Perception Labs' experiment."

Link to Original Source
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South Australia to drop MA15+ video game rating

FatLittleMonkey FatLittleMonkey writes  |  more than 3 years ago

FatLittleMonkey (1341387) writes "While its former Attorney-General Michael Atkinson actively campaigned against an R18+ rating for video games in Australia, the new South Australian Attorney-General John Rau says he will abolish the MA15+ rating in SA after the introduction of an R18+ rating. To better differentiate "between what adults can get and what children can get", games will be rated G, PG, M, and R18+.

"I will push for the South Australian position on MA15+ games to be adopted nationally, but if it isn't, I'm prepared to go it alone," he promised, calling the MA15+ classification "dangerous".

"Besides," Rau says in an interview to Gamespot, "if the latest surveys about the average gamer being a 32-year-old single male who sits at home and plays games all day are correct, then what I am proposing is not going to have much impact at all." Ouch.

All of this follows a review of the classification system in general, so Rau may be reflecting a more general move away from MA15+ in all media."

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