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Comment Re:Overkill for the vast majority of viewers (Score 1) 154

It is true that few viewers will see the increased spatial resolution of 4K without expensive large screens, and even less so for 8K.

But increased spatial resolution is far from the only change in the the new UHD Premium broadcast standards ("4K") or the Super Hi-Vision ("8K") standard mentioned in this story, and all of these other changes have a huge impact that the normal viewer can easily see, no matter what size the TV.

Firstly there is increased colour gamut - before UHD Premium the standard was the BT. 709 colour space, which could only mathematically represent a small subset of the colours that human vision can see. (For example, Pantone's colour of the year 2013, Pantone Emerald 17-5641, can not be represented in BT. 709). The new broadcast standard enlarge the colour space to BT. 2020, which is much larger. Current devices can display roughly the DCI-P3 (digital cinema) colour space, which is already larger than BT. 709. BT. 2020 provides future room for growth beyond even that.

Secondly, there is increased bit depth. Instead of using 8 bits per channel, UHD Premium provides for 10 or 12 bits, and Super Hi-Vision requires 12. 8 bits per channel is just not enough for shadow detail (have you noticed how many videos just have a splotchery of large dark gray blocks in the shadow regions), and causes banding and posterisation in areas of smooth colour gradation like skies and sunsets. (Blu-rays mitigate this by having human compressionists continuously adapt the compression algorithm's parameters on a per-scene basis to work around this).

Then there is increased dynamic range. The current range of brightnesses BT. 709 supports can roughly be described as "everything from black to a glossy white paper under sunlight". Real-world scenes go beyond that, i.e. specular highlights on metal, or the heart of flames, and UHD Premium and Super Hi-Vision provides for that. The idea is not that the entire scene should be brightened to the point that you suntan in front of your TV, but that detail should not be lost by clipping specular highlights, flames, sunsets, full moons and the like.

Then there is increased temporal resolution: UHD Premium and Super Hi-Vision allow frame rates up to 120fps. This will make a large difference in sports with fast-moving objects, it gives additional creative freedom to directors of photography should they decide their stories are better told with higher frame rates.

Comment Re:Yes they did. (Score 1) 572

"Our hardware, our rules"? So, just because a company pays the water bill and thus owns the water, does that mean they can lace the taps in the ladies' bathroom with contraceptives? Just because I own my hi-fi, does that mean I may put the speakers on the balcony, point them at the neighbours, and play it at top volume at midnight? Just because I own a baseball bat, that means I can hit you in the head with it? Since when has the rule "the person who owns an object has total say of any actions performed by or in relation to it" ever applied to any part of society?

Comment Re:Artificial trans fat, not just trans fat. (Score 1) 520

One interesting source of natural trans fats is from ruminants: dairy, beef (grass-fed more so than grain-fed), and the like.

The symbiotic bacteria in a cow's rumen ferment cellulose into fatty acids. Did you know cows are fativores? They may swallow grass, but what they actually absorb is mostly fat.

Some of these fatty acids are trans fatty acids, such as vaccenic acid.

However, since humans have been hunting ruminants for millenia, we have co-evolved with those ruminant trans fats in our diet, to the extent that the evidence seems to be that they are benificial (or, to put it another way, that their absence is detrimental).

So next time you read the label of your feta cheese, and see "Trans fats: 1g" on it, relax. That most likely just refers to natural ruminant fatty acids, which unfortunately need to be totalled up and labelled under the trans fat heading. Iit would be less confusing if regulation excluded ruminant fatty acids, since they are not what we are concerned about.

Comment Re:Atkins for Parkinson's (Score 4, Interesting) 44

The induction phase of the Atkins diet is mostly a ketogenic diet. For the treatment of epilepsy, there are now a handful of variations on the original ketogenic diet used since the 1920s, one of these is known as the "Modified Atkins".

However, there are stricter metabolic goals when on a ketogenic diet and special things to watch out for (too much protein can knock one out of ketosis, for example), so it is best to approach a ketogenic diet as a specialty topic in its own right rather than as something that a different low-carb diet may or may not achieve as a side effect.

There is a lot of recent research on the neuroprotective properties of a ketogenic diet, not just for Alzheimer's, but also for Parkinsons and stroke. See http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2367001/ for example.

Comment Re:Virgin coconut oil contains kinetin (Score 4, Interesting) 44

This comment is actually much more relevant to the OP than it may seem.

As the OP says, Parkinsonson's is essentially a fuel crisis of the brain due to impaired mitochondrial function.

One way to fix this would be to repair the mitochondrial function, as the OP article tries to.

But another way would be to find an alternative fuel source for the brain.

Those who promote coconut oil point of that it it specifically the metabolism of glucose that is impaired in Parkinson's (hence the modern trend of calling it Type III Diabetes). But there are many other energy substrates used my mitochondria, and ketones is one type that brain cells can also make use of.

Coconut oil is high in MCTs (medium-chain triglycerides), which have the unique property of being immediately converted to ketones in the liver. Thus the point of the coconut oil is to give the starving brain something else to run on.

Another way to raise ketones is by using a ketogenic diet (hence the name), as was the standard effective treatment for epilepsy early last century before drugs became available (and ketogenic diets have been making a comeback as alternative treatment when drugs don't help).

In a ketogenic diet, the vast majority of one's energy is derived from fat sources, not carbohydrates. As a side effect of metabolising fat for energy all over the body, ketones are released at a much higher level than otherwise, and these ketones themselves are then available as fuel for the brain (and other tissues).

Comment Re:evils of sugar (Score 1) 157

Sugar is the most basic kind of energy source.

I wish I knew where this meme came from.

Glucose is one of many energy sources that cells can use, but it is far from the only one. Fatty acids, ketones and lactic acid can be utilized for energy too.

One thing that makes glucose special is that it can be used anaerobically, which makes it useful to fuel sudden bursts of activity that exceed the availability of oxygen. But it is much less efficient when used this way, and some of the other fuels listed above are just as efficient, if not more so, when used normally (aerobically).

The other thing that make glucose special is that high levels of it are damaging, because glucose is just so darn reactive. Which is why your body has intricate systems for bringining it down - the normal amount of glucose in the blood is just aboud a teaspoon or two, total.

But somehow we looked at the fact that the body has intricate mechanisms for managing glucose levels, and instead of concluding "glucose is a kind of neccesary evil", we concluded "glucose is the be-all and end-all of energy metabolism, the only fuel that counts".


Comment Lack of tight feedback loops (Score 1) 457

Every bit of code written by a developer represents a hypothesis that "this will have desired behaviour X in the context of the production environment".

Anything that lengthens the time between when that hypothesis was formed, and when that hypothesis is validated or invalidated, decreases productivity in a non-linear way.

This could be anything like:

  • There is no proper testing, so developers have to wait months for the system to be released so they can get the bug reports then,
  • There is a test suite, but it takes ages to run,
  • It takes ages to build/compile the system,
  • Developer lacks the skills to extract the maximum amount of feedback from a single "edit/compile/test/whatever" cycle, so it takes many more cycles to validate the original code,
  • The underlying system/development environment/build system is flaky and often behaves in unanticipated nondeterministic ways, so the developer has to spend a lot of cycles rebuilding/retesting to get a sort of statistical sense whether the code will "work" more often than not,
  • The system involves large database backup files which take ages to copy and restore to a development environment, so it takes ages to work on and validate a production data fix,
  • Deployment of the system to a production, staging, or development environment takes ages and/or is a manual brittle process, so it takes ages to validate whether code will in fact work in the context of the actual complete system,
  • and so on and so forth.

In my experience issues like these are often the number one source of productivity issues in any team and environment.

This does not negate that individual developer skill is a large factor in performance differences, because skilled developers know how to mitigate or prevent such long feedback loop times.

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