3-D model of human retronasal olfactory sense

November 10, 2015 by Bill Hathaway
3-D model of human retronasal olfactory sense

The sweetness of a peppermint candy can be experienced with the nose pinched shut, but flavor is detectable only when the pinch is released and volatiles in the candy are exhaled back into the nose where smell receptors exist.

Exactly how this happens was not known, but now a multi-disciplinary team at Yale University has built a 3-D model of the mechanisms that help bring flavor into our lives.

"The study appears to confirm that humans are especially adapted to enhance this form of smell, and reinforces the idea of the central role flavor plays in ," said Gordon Shepherd, professor of neuroscience and senior author of the paper appearing the week of Nov. 9 in the journal Proceedings of the National Academy of Science.

The collaboration involved flow dynamics researchers from engineering and imaging experts at the medical school, who created a scan of the throat, which in turn was used to create a 3D printout at the Yale Center for Engineering Innovation and Design.

Researchers said they were surprised to find that the dynamic flow patterns suggested that the oropharynx at the back of the mouth was shaped to allow particles to collect in a virtual cavity where they could be efficiently picked up by the exhaling flow, a process known as retronasal smell. In contrast, the flow lines during inhalation passed right by this cavity, thus minimizing the transport of particles into the lungs. This difference occurred even at the relatively low flow rates during normal breathing when we are eating.

3-D printing aids in understanding food enjoyment
A partially completed 3-D printed airway from nostril to trachea with fine structure of the nasal cavity showing. Credit: Rui Ni, Penn State

The researchers speculated that these mechanisms allow us to immediately sense by retronasal smell—as well as touch and taste —whether to accept a substance in our mouth. In addition, inhalation of the volatiles into the lungs is minimized in case those volatiles provide a warning not to accept the food.

Explore further: How to make strawberries sweeter without adding calories

More information: R. Ni et al. Optimal directional volatile transport in retronasal olfaction, Proceedings of the National Academy of Sciences (2015). DOI: 10.1073/pnas.1511495112

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JVK
4.1 / 5 (17) Nov 10, 2015
See also: A key facilitator of mRNA editing uncovered http://phys.org/n...red.html

Accept the facts about odors and pheromones. Feedback loops link odor and pheromone signaling with reproduction http://www.ncbi.n...16290036

The feedback loops link RNA-mediated cause and effect via nutrient-dependent amino acid substitutions in species from microbes to humans.

Nutrient-dependent/pheromone-controlled adaptive evolution: a model. http://www.ncbi.n...24693353

MicroRNA Research Over the Past Decade has eliminated every aspect of the pseudoscientific nonsense about mutations and evolution that is still touted by biologically uninformed science idiots.
See: http://www.geneng...;a=false

Excerpt: "More than 20,000 microRNA-Focused Publications Were Assessed as a Means to Characterize the Field"

RNA-mediated events link atoms to ecosystems via odors and pheromones.
Captain Stumpy
1.8 / 5 (16) Nov 11, 2015
Accept the facts about odors and pheromones
First you have to provide "robust bioassay-led evidence for the widely published claims that four steroid molecules are human pheromones" as noted in this study which demonstrates that pheromones are not supported by validated evidence
http://rspb.royal...full.pdf

RNA-mediated events link atoms to ecosystems via odors and pheromones
considering the above linked study, this is called pseudoscience
adaptive evolution: a model. http://www.ncbi.n.
a better read is "Criticisms of the nutrient-dependent pheromone-controlled evolutionary model"
http://www.socioa...ew/24367

for jk... just because you are a true believer in creationism doesn't mean it is real,,, any more than believing you are invincible because you can "play a children's card game" (ygotas)
anonymous_9001
1.8 / 5 (16) Nov 11, 2015
MicroRNA Research Over the Past Decade has eliminated every aspect of the pseudoscientific nonsense about mutations and evolution


miRNAs are not an alternative to mutation and evolution. That's like saying the existence of apples disproves the existence of oranges. Pure nonsense because they're not contradictory. Mutations alter DNA sequence. miRNAs bind to mRNAs and alter how they're read. They don't play the same role and are not mutually exclusive.
JVK
4.1 / 5 (17) Nov 11, 2015
Mutations link virus-perturbed protein folding to genomic entropy. Claims about beneficial entropy can be placed into the context of http://arxiv.org/...11.03076

Ellis et al., (2015) answers questions that address the comments about "emergence" in http://matpitka.b...tor.html

Excerpt: "...does it make sense to talk about dark variants of cell and cell membrane? Can one tell whether it was pro-cell or bio-molecules that emerged first? It seems that all these structures could have emerged simultaneously. What emerged was dark matter and its emergence involved the emergence of all the others. Hens and eggs emerged simultaneously."

My comment: It has never made sense to any serious scientist I know to place anything known to other serious scientists about the links from atoms to ecosystems into the context of theories about simultaneous hen and egg "emergence."

Adding mutations and evolution explains nothing.
JVK
4.1 / 5 (17) Nov 11, 2015
Re:
Adding mutations and evolution explains nothing.


See the thesis by anonymous_9001 (aka Andrew Jones).
http://www.scribd...s#scribd

"Despite their challenges, ribozymes have made an interesting niche for themselves in the field of abiogenesis. The evolution of a successful RNA polymerase ribozyme is a lofty goal. While its discovery would not be the be-all and end-all of abiogenesis research, it would represent an important stepping stone between prebiotic chemistry and life. The encapsulation of such a ribozyme is also an important step, as it would enable a system of heredity and evolution through natural selection. Based on progress in current research, it is only a matter of time before that ribozyme is discovered."

Based on the report from Ellis et al., (2015), scientific progress has eliminated Jones' perspective on the space / time continuum.
JVK
4.1 / 5 (17) Nov 11, 2015
Re:
...scientific progress has eliminated Jones' perspective on the space / time continuum.


Serious scientists have never considered Jones' perspective on the space / time continuum because it is pseudoscientific nonsense. Captain Stumpy enjoys touting pseudoscientific nonsense because he is a biologically uninformed science idiot.

Serious scientists start with top-down causation and are required to link atoms to ecosystems.

When they make claims about emergence, and/or mutations and evolution, pseudoscientists are recognized by serious scientists who ignore pseudoscientists and continue to publish works that link atoms to ecosystems via the conserved molecular mechanisms of biophysically constrained RNA-mediated protein folding chemistry, which are exemplified in all living genera via the amino acid substitutions that stabilize their organized genomes.

See also: "Top-down causation: an integrating theme within and across the sciences?"
JVK
4.1 / 5 (17) Nov 11, 2015
"Top-down causation: an integrating theme within and across the sciences?"
http://rsfs.royal...abstract

Excerpt: "The papers by Jaeger (microbiology) and Noble (physiology) are strong steps forward in this regard. This is perhaps the area where most needs to be done, across the board in all domains. Areas where striking progress is being made in this regard are epigenetics [22] and social neuroscience [23]. These papers are in fact dealing with top-down causation: the way they provide experimental confirmation of this concept needs to be made more explicit."

There may be nothing more explicit than experimental confirmation of the links from atoms to ecosystems in "Structural diversity of supercoiled DNA" http://dx.doi.org...omms9440

Excerpt: "Each of these structural features may be differentially recognized by the proteins, nucleic acids, and small molecules that modulate DNA metabolic processes."
JVK
4.1 / 5 (17) Nov 11, 2015
Re:
small molecules that modulate DNA metabolic processes.


Viral microRNAs perturb the metabolic processes that link metabolic networks to genetic networks in the organized genomes of all living genera. The idea that perturbed metabolic processes can be linked to the evolution of a new species via mutations is the most ignorant idea that has ever been proposed by biologically uninformed science idiots who have popularized their idiocy by ensuring that all explanations of biologically-based cause and effect are labeled as if they were "creationist" beliefs.

The
small molecules that modulate DNA metabolic processes
are created in the context of experience-dependent de novo creation of olfactory receptor genes that link the "3-D model of human retronasal olfactory sense" to the pheromone-controlled physiology of human reproduction via changes in the microRNA/messenger RNA balance that link atoms to ecosystems in all living genera.
anonymous_9001
1.8 / 5 (15) Nov 11, 2015
perspective on the space / time continuum


The topic of this article has nothing to do with cosmology.

It's well documented that conspiracy theorists are prone to making random connections between unrelated topics and the vast majority have some sort of psychopathology. That explains quite a bit about you. Is that why you use "link" so often to try to connect distant biological concepts? Seek help.

Regarding quoting Ellis again- need I remind you that he has no qualms with mutation and selection? The environment and selective pressures are what make up the top-down causation.

Natural selection as usually envisaged is a form of top down causation (because the environment is a major causal factor in the outcomes). Selection is a key process in the rise of complexity. That is quite clear in what I have written. Indeed I claim that multilevel selection is a key to complexity

-Ellis
JVK
4 / 5 (16) Nov 11, 2015
Multilevel selection links atoms to ecosystems via supercoiled DNA. Ellis is not an expert on supercoiled DNA, or "natural selection."

He is an expert on the need to link top-down causation to biophysically constrained nutrient-dependent protein folding chemistry, which is what I did in my series of published works on RNA-mediated amino acid substitutions linked to the stability of organized genomes via the de novo creation of olfactory receptor genes.

conspiracy theorists are prone to making random connections between unrelated topics and the vast majority have some sort of psychopathology.


Clearly, evolutionary theorists are psychopaths who take their random connections to the extreme, except when they are asked to explain the "re-evolution" of the bacterial flagellum in 4 days.
anonymous_9001
1.9 / 5 (14) Nov 11, 2015
except when they are asked to explain the "re-evolution" of the bacterial flagellum in 4 days.


There is no minimum time required for such simple changes to take place. There were only a couple mutations. It's not as though the entire flagellar mechanism was reinvented from scratch.
JVK
4 / 5 (16) Nov 11, 2015
They reported changes in two nutrient-dependent RNA-mediated amino acid substitutions and referred to the substitutions as mutations.

There is no minimum time required for such simple changes to take place.


What simple changes? The microbes resurrected a complex functional structure akin to what has been reported by theorists in the context of the evolution of the eye.

How long do you think it took for the simple changes that led to reports of the mutation-driven evolution of the eye to take place?

See also: http://www.scienc...4131.htm
Excerpt: "The greatest absence of evolution ever reported has been discovered by an international group of scientists: a type of deep-sea microorganism that appears not to have evolved over more than 2 billion years."

Do you think that these microbes in the ocean sediment are waiting too long to mutate into organisms with eyes or humans with eyes and brains?
Captain Stumpy
1.8 / 5 (15) Nov 11, 2015
referred to the substitutions as mutations.
In biology, a mutation is a permanent change of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA or other genetic elements. Mutations result from damage to DNA which is not repaired, errors in the process of replication, or from the insertion or deletion of segments of DNA by mobile genetic elements.[1][2][3]
https://en.wikipe...Mutation

See also: Nomenclature: https://en.wikipe...Mutation#Nomenclature

Do you think that
it doesn't matter what anyone thinks (or believes), only what can be proven
take for instance, the zephir socks uprating your posts
this doesn't make your posts valid any more than owning an axe makes you Lizzie Bordon
nor does it mean any of Anon's downrated posts are invalid

the evidence speaks for itself, and the evidence demonstrates you are a liar and pseudoscience poster (and creationist, and fraud, etc )
anonymous_9001
1.8 / 5 (15) Nov 11, 2015
RNA-mediated amino acid substitutions


What mechanism would that be through? Now that you've clarified RNA-directed methylation, let's finally clear this up.

What simple changes? The microbes resurrected a complex functional structure akin to what has been reported by theorists in the context of the evolution of the eye.


They still had perfectly intact flagella genes. FleQ is a protein that regulated flagella gene transcription. What they did was disable FleQ, which shut off transcription of the flagella genes. NtrC normally regulates other genes, but it's similar in structure to FleQ, so it has some overlap with that regulatory region and even more so with the couple mutations they observed.

I will admit it's a bit disingenuous to say they completely resurrected it. They just added a new on/off switch, essentially, to make up for the one they broke.

JVK
4 / 5 (16) Nov 11, 2015
They just added a new on/off switch...


Are you claiming that the new nutrient-dependent pheromone-controlled on/off switch "re-evolved?"
JVK
4 / 5 (16) Nov 11, 2015
Mutations result from damage to DNA which is not repaired...


How does damaged DNA lead to the evolution of a new species, or "re-evolution" of a functional bacterial flagellum in 4 days?

See also: New findings shed light on fundamental process of DNA repair http://phys.org/n...tml#nRlv

See also: http://www.nation...d-french

Excerpt: "...a systematic worldview that fosters dependency and helplessness while silencing and marginalizing moral and political opposition. Political correctness is a fundamental threat to hope and freedom."

My comment: That systematic worldview can be directly linked to neo-Darwinian theories, which ignore the direct links from ecological variation to ecological adaptation.
JVK
4 / 5 (16) Nov 11, 2015
Re:
...neo-Darwinian theories, which ignore the direct links from ecological variation to ecological adaptation.


The politically correct biologically uninformed mainstream researchers link mutations to pathology and to the evolution of new species. Informed serious scientists link viruses, which are the cause of the mutations, to all pathology. The serious scientists start with nutrient-dependent base pair changes and link them from RNA-mediated events to chromosomal rearrangements and all biodiversity via DNA repair. The biologically uninformed mainstream pseudoscientists start with de Vries 1904 definition of sudden energy jumps, which he called "mutations."

[cont]
JVK
3.9 / 5 (15) Nov 11, 2015
[cont]

They link their assumptions about how long it would take mutations to lead to the evolution of one species to another species and claim that their assumptions about de Vries definition are supported by the fossil record. That is the politically correct thing to do. If you do not believe that definitions and assumptions should be linked to the evolution of all biodiversity, you will be challenged to produce evidence of creation, by people who are too stupid to understand biologically-based cause and effect in the context of everything currently known about physics, chemistry, and molecular epigenetics.

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