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5,211 questions with no upvoted or accepted answers
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21
votes
0answers
392 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 ...
15
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0answers
470 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 ...
13
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0answers
232 views

Does vaccination lead to short-term secondary infection suceptibility?

For clarity, here is a summary of my question, per anongoodnurse's comment: Does a lower peripheral lymphocyte count resulting from recent immunization render us more susceptible to infection by other ...
13
votes
1answer
1k views

Deliberately choosing one nostril to breath 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 ...
12
votes
2answers
262 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 ...
11
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0answers
157 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 ...
11
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0answers
129 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 ...
11
votes
0answers
400 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 ...
10
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0answers
261 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?
10
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0answers
402 views

What percentage of the genetic variance is explained by the 'n'- most important loci?

Introduction Standard models in population genetics look up at the evolution of few loci which impact fitness. The variance in fitness is determined by the genetic variance and the environmental ...
10
votes
1answer
265 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 ...
9
votes
0answers
175 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 ...
9
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0answers
371 views

Why are adenoviral vector vaccines safe in terms of insertion mutagenesis due to genome integration and E4 region's proteins effects?

Disclaimer: I'm neither a genetics professional nor an anti-vax fanatic, I just tried to compare COVID-19 vaccine types currently available on the market and got some questions that I'd like to answer ...
9
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0answers
158 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 ...
9
votes
1answer
178 views

What species is this aromatic plant found in a mountainous region of Greece?

This plant was found in the Taygetos mountains, Greece, and had a lemony smell. Small plant about a foot high. The shiny recurved leaves are reminiscent of rosemary, and the dry seed-heads seem ...
9
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0answers
788 views

Genetic expression in interspecific hybrids

Referring to interspecific hybrids, I have the following two questions:- Quoting from wikipedia:- The offspring of an interspecific cross are very often sterile; thus, hybrid sterility prevents ...
9
votes
1answer
529 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 ...
8
votes
0answers
136 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 ...
8
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0answers
55 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 ...
8
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0answers
3k views

Do sharks fart?

My son is 5 and I'm encouraging him to be curious and ask questions of the world around him. He asked if sharks fart and how does it smell? He feels that it would smell of fish and be disgusting. He ...
8
votes
0answers
282 views

How to estimate heritability from breeding data

I have a lot of plant-breeding data (tens of thousands of results) that are composed of phenotypes of parents and offspring. The plants however went trough years of selection and it is not balanced. ...
8
votes
0answers
238 views

What are the secondary structure requirements for cell-penetrating peptides AKA protein transduction domains

Cell penetrating peptides. Cell penetrating peptides (CPPs) are a class of short amino acid sequences which are sufficient for crossing cell membranes and delivering themselves along with any attached ...
8
votes
2answers
907 views

What is, (and what isn't) "kinetic replication" as it applies to molecules and to living organisms?

CNN's World's first living robots can now reproduce, scientists say describes "xenobots"; clusters of stem cells that move around and by this motion occasionally push enough free stem cells ...
8
votes
2answers
740 views

How does LCR compare to Assembly PCR

The question pretty much explains itself. How do the two methods compare? I've always used Assembly PCR but the method is prone to mistakes and I'm curious how it compares to Ligase Chain Reaction (...
7
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0answers
107 views

How do rats open a walnut?

What techniques do rats use to open a walnut? What are the traces they leave in nature? I have a book on traces that wild animals leave in nature, but it only explains squirrels (splitting the walnut ...
7
votes
0answers
159 views

How does a virus stick to a non-biological surface?

Recent events has triggered an renewed interest in understanding how a virus is able to stay on a surface. For sake of argument, let's assume we are dealing with a Corona-type virus. One can then ...
7
votes
0answers
84 views

What insect is this case from?

I found this insect case in my garden in the south of Melbourne (Australia), under some dried leaves from a tree that I'd cut down. It is 8 cm long, which is pretty big for an insect! The photo is of ...
7
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0answers
220 views

What is this underwater creature?

West Bali, about 10 meters deep. Body is roughly 10 cm across. Does not move.
7
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0answers
156 views

Found in blood sample - what is it? Hopefully not a nemotode-

After examining someone's blood - through microscope - I found these. There were some more that were not photographed. Could someone please inform me on what these are? Maybe abiotic material on the ...
7
votes
0answers
137 views

Could these be Mycetozoa?

I found this on a forest in Mexico City. It was kind of a warm day (around 15°C). It had been raining a few days prior and it was quite humid, but not suffocating. This orange thing was on top of a ...
7
votes
0answers
284 views

Insect identification (Brazil, orthoptera?)

This insect appeared in my indoor yard, in southeastern Brazil. The body is roughly 2cm in length and it makes very distinct beeping sounds, in a pattern that sounds almost like morse code, unlike the ...
7
votes
1answer
179 views

What metabolically happens when an egg fuses with the nucleus of a somatic cell

In stem cell biology, it is recognized that embryonic stem cells are transcriptionally inactive for the first 3 days of development. However, during somatic cell nuclear transfer, the nucleus is ...
6
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0answers
26 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 ...
6
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0answers
62 views

Grasshopper vs Tarantula?

This past weekend (October 2021) while hiking west of the VLA in New Mexico (near Datil, NM, ~2200m elevation) my wife and I came across a strange sight. A small (5cm long), likely immature, ...
6
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0answers
53 views

What are the additional considerations for primer design in ancient DNA?

I'm familiar with the principles of primer design and have previously designed primers for use in modern DNA. However, in my current project I am working with ancient DNA (nuclear gene) and need to ...
6
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0answers
72 views

Recombinations between Distant coronaviruses

With recombination I mean long ones, say > 1000 nucleotides, so that the two parents must be coronaviruses and the two pieces of genomes must have compatible genomic coordinates for the recombinant ...
6
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0answers
33 views

Bacterial endosymbiosis of bacteria

Endosymbiosis was crucial to the development of complex life and it continues to happen to this day. The origin of mitochondria see bacterial guests in archaea hosts, some of which later took in ...
6
votes
0answers
152 views

What species is this golden fly?

Last summer I was visited by this unusual golden fly, whose kind I have never seen before. It was impossible to scare away so I could take relatively good pictures. The pictures on this hobbyist page ...
6
votes
2answers
181 views

Help identifying a mushroom found in Raymond, WA, USA

Hello dear mycology wizards! Could you help me figure out what's the name of this species. I found the mushrooms in a forest near to Raymond, WA. The area was quite wet and mossy, but not a swamp. ...
6
votes
0answers
69 views

Correlation brain size and muscle volume

I have 3 dogs that weigh ≈ 5 kg, ≈ 20 kg and ≈ 45 kg. The smallest dogs whole head would fit in the mouth of the biggest dog. Although I haven't measured it exactly but by just looking at the dogs I ...
6
votes
0answers
81 views

What is the fastest way to crystallise lysozyme (for student course)?

High school sudents are going to visit my university and I plan to demonstrate crystallisation of lysozyme. I ordered pure lysozyme from VWR. I can easily crystallise this within 15 min in batch (4% w/...
6
votes
0answers
109 views

What is this colourful insect?

Found this colourful insect in our garden. It measures about 1.5cm. I am from Kuching, Sarawak, Malaysiai
6
votes
0answers
161 views

Can a dividing cell that skipped DNA replication become cancerous?

Let's assume that a cell fails to replicate its DNA during the S Phase of the cell cycle. Let's also assume that the appropriate CDKs are inactive (perhaps due to mutation or lack of cyclin proteins ...
6
votes
0answers
241 views

Could being exposed to excess UV in the arctic lead to a human eye color change? If so, what is the mechanism?

The CBS News article Expedition Antarctica: A father and son's journey to save the planet says (in part): Thirty-two years ago, Robert Swan made history as the first person to walk to both poles. ...
6
votes
0answers
136 views

Can anyone identify this seed or nut?

I found many of these nuts in a botanical garden in Sweden (outside, not in a greenhouse) but was unable to find the plant it belonged to. The garden has species from all over the world. I don't ...
6
votes
0answers
167 views

How optimal are the distances of voltage-gated ion channels on axons?

In both myelinated and not-myelinated axon segments ("axons" for short) there are theoretically maximal distances of voltage-gated ion channels beyond which propagation of the action potential would ...
6
votes
0answers
101 views

Any references contradicting Hormesis from low dose studies?

I've recently read some papers on Hormesis (the stimulatory effect of low doses of substances toxic at high doses). The papers are all published in respected peer-reviewed journals, here, here, and ...
6
votes
0answers
551 views

Can dopamine antagonists be used as dopamine upregulation?

Can dopamine antagonists such as Thorazine that are used to treat schizophrenia and bipolar be used to upregulate dopamine in the long term in healthy (non schizophrenic or bipolar) users to get a ...
6
votes
0answers
341 views

Do animals get "unhealthily" fat in the wild?

Looking at a picture of a seriously fat cat, apparently directly nurtured by humans, popping up in a language learning app, I started wondering: do animals "in the wild" (this might be ambiguous, but ...
6
votes
0answers
829 views

Does variation in human gut length vary predictably with diet of ancestors?

Background: Numerous online searches, textbooks and other sources seem to pin the average length of the human gut from mouth to anus (oroanal) between about 5-10m in length. To pick a reputable ...

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