Unanswered Questions

5,922 questions with no upvoted or accepted answers
23 votes
0 answers
509 views

Effect of Aging on SA node's sympathetic fibers

I am trying to understand the effect of aging on the sympathetic fibers of SA node. I know that aging shifts the vagal curve to left in frequency due to aging. However, I am interested if aging has ...
18 votes
0 answers
632 views

Identifying Some Kind Of Fossil

This was found off the coast of Ireland by a friend of mine. The running gag is it's some kind of fetish or totem and should be immediately discarded, but we're interested in whether it's perhaps a ...
17 votes
1 answer
2k views

Deliberately choosing one nostril to breathe through

James Nestor, on pp. 41-42 of his book Breath: the New Science of a Lost Art, claims the following. The right nostril is a gas pedal. When you're inhaling primarily through this channel, circulation ...
15 votes
0 answers
251 views

Is it known how some heat-resistance Bacillus spores repair their DNA after having been heated to 420 °C? (but not much higher)

Background Discussions below several recent posts in Space SE (links below) indicate that bacterial spores are a serious problem when considering how to prevent a future spacecraft mission to ...
13 votes
0 answers
199 views

How do the biophysics of how cerebrospinal fluid mechanically protects the brain work?

The two mechanisms I've seen mentioned are the cerebrospinal fluid (CSF) acting as a hydraulic cushion or shock absorber, and how CSF creates a micro-gravity environment through buoyancy. I have very ...
13 votes
1 answer
201 views

What actually kills a plant that requires winter dormancy if it is kept indoors all year?

In bonsai practice, beginners will commonly purchase a juniper (often Juniperus procumbens 'Nana'), which is an outdoor tree, and keep it inside all year. The tree invariably dies. It is commonly ...
13 votes
1 answer
287 views

Identification of an animal building

I live in south-west Germany and today while mowing the lawn I discovered a strange structure. It looks like a molehill on which additional branches were placed. This kind of branches are easy to find ...
13 votes
2 answers
306 views

Are there certain symmetric-pair muscles that are slightly bigger and NOT due to handedness?

Ok, hear me out, I was just thinking about an article in Nature I read in the past titled "Scrotal asymmetry in man and in ancient sculpture"$^{\dagger}$ and more recently an entire medical textbook ...
12 votes
0 answers
343 views

ID request ~2mm insect monstrosity

This tiny monstrosity (~2mm in length) was inside of some kind of "flat tent cocoon" on a pepper plant leaf in Washington state, USA. Not sure what's going on here. Is it malformed or infected?
12 votes
0 answers
452 views

Anatomical Angle Made by the Fingers of an Extended Palm

Does the angle made by the fingers (excluding the thumb) of an extended palm (as shown in the figure below) have a name (such as the Lovibond or Cobb angle, for instance) ? I have already checked ...
12 votes
1 answer
387 views

I am trying to identify this plant

I am trying to identify this medium arching shrub growing to about 1.5m high x 2m wide in the subtropical climate of the Mt Coot-tha Botanic Gardens in Brisbane, Australia. Unfortunately there was no ...
11 votes
0 answers
141 views

The almost extinct dinosaurs

Dinosaurs split into "lizard-hipped" and "bird-hipped" dinosaurs. Of these two groups, only the "lizard-hipped" (Saurischia) survived (these names are backwards). Of ...
11 votes
0 answers
254 views

Where does Darwin state his "principle of multiple utility"?

I have never heard of Darwin's 'principle of multiple utility', but several papers refer to it. For example, from Darwin at the molecular scale: selection and variance in electron tunnelling proteins ...
10 votes
1 answer
758 views

Identify this vertebra

I was walking on the beach in New Jersey (U.S.), at about 40 degrees longitude, and found this bone. It's not a fish. The long process in the front is interesting. It is likely a C2 vertebra. I looked ...
9 votes
0 answers
289 views

The village of Twins — Mystery behind and Scope

With the presence of more than 200 twins, Kodinhi , a village situated in Malappuram District in Kerala , India , is popularly known as the "Village of Twins".This phenomenon of large ...

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