Follow Slashdot blog updates by subscribing to our blog RSS feed


Forgot your password?

Slashdot videos: Now with more Slashdot!

  • View

  • Discuss

  • Share

We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).


Comment: Re:And the almond trees die. (Score 1) 416

by reve_etrange (#49325267) Attached to: How 'Virtual Water' Can Help Ease California's Drought

Make something as yummy _and cheap_ as meat

Store bought meat substitutes are expensive, but I think with heightened demand the price is likely to go down over time. Soy curls are already cheap, and they can be really good if made right.

There are lots of easy - but not well known - vegan cooking techniques that make a huge difference in the weirdo vegan substitute department, especially for cheese (e.g. calcium-setting pectin) and eggs (black salt, egg salt, turmeric for color). Meat is actually the hardest IMHO, though homemade seitan is actually cheap.

plain vegetables aren't

To me, well prepared vegetables are as tasty. Part of that is relearning how to cook with a few good vegan cookbooks and using the techniques that work, but another part is the way your tastes adapt to what you eat. Tastebuds are regenerated completely every few weeks, and as they do so they adapt to find whatever you've been eating recently to be "good."

I've been vegan for a couple of years now and I've never wanted for filling, flavor-full plant based foods. On the other hand, I'm not too strict with myself since I'm only vegan for environmental reasons. Animal agriculture is the single largest source of human climate impacts of all kinds - if you dig up some numbers it looks like we can pretty much export Western lifestyles and quality of life to everyone on Earth, as longs as animal agriculture is reduced by ~90%.

Comment: Re:And the almond trees die. (Score 2, Informative) 416

by reve_etrange (#49314449) Attached to: How 'Virtual Water' Can Help Ease California's Drought

You only have to water alfalfa

Alfalfa is real water guzzler in California. Alfalfa, hay and pasturage account for about half of all Californian water consumption. The real water savings are to be found in reducing consumer demand for animal products - nothing else will impact this water efficiency bottleneck.

Comment: Re:And the almond trees die. (Score 1) 416

by reve_etrange (#49314421) Attached to: How 'Virtual Water' Can Help Ease California's Drought

There are lots and lots of ways to lower the water usage of both the general population and water intensive applications such as farming.

Absolutely - although agricultural consumption is the efficiency bottleneck in CA. Drip irrigation is not required and most farms use insanely inefficient sprinkler systems. However, some crops really can be cut back significantly - if the will is there - in order to generate water savings.

I'm talking about alfalfa, hay and pasturage, together accounting for about half of all Californian water consumption. Animal agriculture dwarfs every other user of water - even almonds are irrelevant in comparison - and unlike almond orchards, these crops can be reduced rapidly to reflect decreased consumer demand for animal products.

I'll say it again: reduced consumer demand for animal products is the only thing that is likely to ease water stress in California and elsewhere over the long term.

Comment: Re:These people - and their politicians - idiots (Score 2) 416

by reve_etrange (#49314369) Attached to: How 'Virtual Water' Can Help Ease California's Drought

What they should do (should have done long since) is put in a series of desalination plants

You mean like the half dozen existing plants and 15+ proposed for construction across the state?

You are also apparently unaware that There Ain't No Such Thing As A Free Lunch. Desalination from seawater costs about 8.5 kWH / m^2. That is a lot of power. Even ignoring the environmental impact, desalination is extremely energetically expensive.

Comment: Re:John Hilder lives. (Score 1) 416

by reve_etrange (#49314289) Attached to: How 'Virtual Water' Can Help Ease California's Drought

Not the millionnaire Hollywood crowd decrying the 1% while filling there private pools with tyhosaunds of gallons of water per year. Oh the vinyarder's who sell there $100 a bottle wine to the Hollywood crowd.

Sorry, but if you look at actual quantitative data on water use, it is animal agriculture which is by far the largest source of water consumption and water waste in California. Almonds, Hollywood pools and wine are all as nothing compared to the water used for alfalfa. Alfalfa, hay and pasturage account for about half of the states entire consumption.

Unfortunately, you can't just put the blame on 1%ers. You too will have to drastically reduce your water footprint - by cutting back on meat.

Comment: Almonds are mentioned to distract you from Alfalfa (Score 1) 416

by reve_etrange (#49314259) Attached to: How 'Virtual Water' Can Help Ease California's Drought

About half of California's water is used for alfalfa, hay and pasturage. Next to that, every other Californian water use is almost irrelevant - even almonds.

When you look at the numbers, it's clear water stress can only be managed by reducing consumption of animal products and restricting animal agriculture.


Excess Time Indoors May Explain Rising Myopia Rates 143

Posted by timothy
from the buildings-hate-us dept.
Nature reports that an unexpected factor may be behind a growing epidemic of nearsightedness: time spent indoors. From the article: Because the eye grows throughout childhood, myopia generally develops in school-age children and adolescents. About one-fifth of university-aged people in East Asia now have this extreme form of myopia, and half of them are expected to develop irreversible vision loss. This threat has prompted a rise in research to try to understand the causes of the disorder — and scientists are beginning to find answers. They are challenging old ideas that myopia is the domain of the bookish child and are instead coalescing around a new notion: that spending too long indoors is placing children at risk. “We're really trying to give this message now that children need to spend more time outside,” says Kathryn Rose, head of orthoptics at the University of Technology, Sydney.

Comment: Head Tracking (Score 1) 100

by reve_etrange (#49258013) Attached to: Ask Slashdot: Mouse/Pointer For a Person With Poor Motor Control

Head tracking may work well, depending on ability to control head/neck. There are several methods (mostly originating in the flight sim community).

1. Face tracking (very easy to try, FaceTrackNoIR or Opentrack)
2. Head tracking with IR clip (bit more reliable than face, many DIY guides out there)
3. Head tracking with Aruco marker (available in Opentrack)

Comment: Re:Electron transport in biological systems (Score 1) 188

by reve_etrange (#49213209) Attached to: The Origin of Life and the Hidden Role of Quantum Criticality

Are there any existing models of electron transport in biological systems?

Good question! The answer is yes, although they are not even mentioned in this unreviewed manuscript (which seems like hokum to me). Electron transfer in proteins is particularly well understood in the context of Marcus theory. The wiki article isn't great, but it has some good information and further references. A key insight is the "inverted driving force effect," an experimentally validated prediction of Marcus theory that electron transfer rates actually start to decrease if the transfer reaction is too exergonic (energetically favored).

Without going into a ton of detail, quantum effects are actually quite important for electron transfer, and some enzymes even encourage tunneling, mostly of electrons, as part of catalysis. Considering that the de Broglie wavelength of a 10 kJ electron is about 18 angstroms (biologically relevant scales), it's not really that surprising. Frequently, there are favored tunneling pathways through enzymes which electrons tend to follow.

Enzymes also sometimes utilize nuclear tunneling (i.e. tunneling proton/hydrogen/hydride), which is really, really cool. I am a fan of this paper which shows how tunneling is is encouraged through dynamic gating motions in a enzyme on the chlorophyll production pathway.

Comment: Re:Assuming a grand meaning seems to be overreachi (Score 1) 188

by reve_etrange (#49213175) Attached to: The Origin of Life and the Hidden Role of Quantum Criticality
As a current biochemist, I do wonder why the paper doesn't even mention Marcus theory or other previous work in enzymatic charge transfers. There really are some sweet quantum effects in biology, like enzyme-catalyzed proton tunneling, but I think the unreviewed manuscript under discussion here is hokum.

Comment: Re:quantum tunneling? (Score 1) 188

by reve_etrange (#49213171) Attached to: The Origin of Life and the Hidden Role of Quantum Criticality

Tunneling (mostly of electrons) is actually widespread in proteins, and its not hard to see why that is when you consider that the de Broglie wavelength of a 10 kJ electron is around 18 angstroms (these are relevant energy/distance scales in enzymes). Search "Marcus theory" for more information...

What's really cool is that some enzymes actually boost tunneling probabilities (e.g. through particular short-timescale motions) as an essential component of catalysis. In some cases, tunneling even occurs for larger particles like protons/hydrogens/hydrides. I really like this paper, for example, which shows how proton tunneling is essential in a light-activated enzyme involved in an early stage of chlorophyll synthesis in some plants.

Unfortunately, the unreviewed manuscript from TFA seems like nonsense to this biochemist. It doesn't seem to line up with, or even reference, any of the five decades of existing science in the area.

Aren't you glad you're not getting all the government you pay for now?