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[inteuniso]

Stein Sigurdsson was appointed Science Director of arXiv.

No idea what this means, but I always enjoy spending even five minutes looking at the most recent papers. Far more interesting than checking any newspaper imo. My most interesting reads I found today are the geometric and physical bounds that lead to sinus cavities being shaped the way they are (also learning that they are best described as biological air humidifiers present within all vertebrates), the initial experimentation of stretchable CMOS interconnects, and bouncing/oscillating universes to explain cosmogenesis instead of a singularity.

[Max™]

Ekpyrotic universe theory isn't it?

[Paxiecrunchle]

Posting to watch[do I really need a citation for that?]

[Il Palazzo]

Ekpyrotic universe theory isn't it?

As far as I can see, that's a different kind of cyclic universe model - in particular, the paper has no oscillations for flat universes, unlike the ekpyriotic model.

[inteuniso]

From the quantitative biology side of things: by providing high-offers that can be rejected, therefore allowing for non-monotonic rejections (rejecting offers too high or too low), an environment was created in the Ultimatum Game for the testing of separate strategies for fairness, selfishness, altruism and spite. I don't think I'm doing a good job explaining it so here's the link.

Accordingly, we have explicitly shown that
altruism inhibits the evolution of fairness, whereas spite promotes the evolution of
fairness. Fairness first gains an advantage over selfishness when the fair strategy with
the non-monotonic rejection is added, and thus we have found that the non-monotonic
rejection can cause fairness to overcome selfishness, which cannot happen without the
high-offer rejection.

On the Neuroscience side, we have the modeling of the transition from linear to chaotic systems for memory storage in random networks and the optimization of such i.e. neurons

Spoiler: Optimal Memory Storage in Driven Random Networks, Jannis Schuecker, Sven Goedeke and Moritz Helias (click to show/hide)

Therefore it is plausible that the optimal memory appears at a point where local amplification of the external input is large enough, but intrinsic chaoticity is still limited.

Finally, on biochemistry, we have a study providing a structure for non-zero steady states of Chemical Reaction Networks, like continuous-time markov-chains of stochiometric variability.

We show, for non-trivial examples, that in this manner we can predict to high accuracy, any moment of interest, for CRN's with non-zero deficiency and non-factorizable steady states.

[Paxiecrunchle]

 I'm confused mostly because I don't know what the term monotonic means.

And any rate I had recently read a bit about zebra stripes having a repelling effect on biting insects, and that an scientific paper was written about this, I just can't quite remember the name of the authors, has anyone else heard about this? I think it was from a few years ago?

[Reelya]

Monotonic means it only goes in one direction, e.g. a graph that goes up, down, then up again, is not monotonic.

e.g. inteuniso is talking about something that's rejected if too high or to low, so the optimal value is in the middle and both left and right extremes are valued lower, so it's not monotonic.

[bloop_bleep]

Monotonic means it only goes in one direction, e.g. a graph that goes up, down, then up again, is not monotonic.

e.g. inteuniso is talking about something that's rejected if too high or to low, so the optimal value is in the middle and both left and right extremes are valued lower, so it's not monotonic.

In precise terms, a given function f is monotonically increasing if for every x,y in the domain of f such that x>y the statement f(x)>f(y) is true. Monotonically decreasing is the opposite.

[Bumber]

In precise terms, a given function f is monotonically increasing if for every x,y in the domain of f such that x>y the statement f(x)>f(y) is true. Monotonically decreasing is the opposite.

Shouldn't it be f(x)≥f(y)?

[Madman198237]

That depends, does it count as "Always increasing" if it plateaus completely at any point? (i.e., is neither increasing nor decreasing)

[Bumber]

That depends, does it count as "Always increasing" if it plateaus completely at any point? (i.e., is neither increasing nor decreasing)

https://en.wikipedia.org/wiki/Monotonic_function
"A function that increases monotonically does not exclusively have to increase, it simply must not decrease."

f(x)>f(y) describes a "strictly increasing" function, which is a subset of monotonic functions.

[bloop_bleep]

In precise terms, a given function f is monotonically increasing if for every x,y in the domain of f such that x>y the statement f(x)>f(y) is true. Monotonically decreasing is the opposite.

Shouldn't it be f(x)≥f(y)?

Yes, that's right.

[Starver]

‼Magmapump‼ (that's a link, BTW)

[Reelya]

You know inbreeding isn't all bad. It's used in animal husbandry to try and get novel traits to appear - e.g. rare recessive genes are probably bad, but hey, they might just turn out to be awesome:

http://www.news.com.au/technology/science/human-body/genes-of-small-indiana-amish-community-carry-mutation-that-could-be-the-key-to-antiageing/news-story/56096b9b9c607db02a104e6e2654a955

A SMALL Indiana Amish community might hold the key to the genetic fountain of youth.

Scientists found members of the Old Order Amish community carry a copy of what is being described as the first ever anti-ageing genetic mutation.

Medical researcher Douglas Vaughan first started studying the group after noticing a high occurrence of a rare bleeding disorder caused by a mutation on both copies of the SERPINE1 gene, which prevents the regulation of a protein called PAI-1 — needed to dissolve blood clots.

However, those members with the mutation on only one copy of the gene — not both — were found to not have the bleeding disorder.

In fact, those with the single mutation appeared to actually gain advantages from it.

It was discovered Amish carriers of the single mutation lived on average to be 85, which was about 10 years longer than their peers.

Carriers of the mutation also had a zero rate of Type 2 diabetes, while those without had a rate of seven per cent. This was despite leading the same lifestyle and consuming similar diets.

...

The suggestion of anti-ageing was furthered by the fact those with the mutation also had 10 per cent longer telomeres — the caps at the end of each strand of DNA that protect our chromosomes like the plastic tips at the end of shoelaces.

Basically, if one copy of this gene adds 10 years to your life, but two copies are bad then we could probably arrange a gene drive that makes sure you only carry one copy. So all those "only good if you have exactly one copy" genes could be utilized. Or, if we knew more about how the whole thing works than that, we could reverse-engineer it so that it works all the time with 1 or 2 genes.

[Starver]

It's lucky, then, that the Amish are notorious Early Adopters of new scientific and technological developments!