Scaling of Haversian canal surface area to secondary osteon bone volume in ribs and limb bones

  • by John G. Skedros, Alex N. Knight, Gunnar C. Clark, Christian M. Crowder, Victoria M. Dominguez,  Shijing Qiu, Dawn M. Mulhern, Seth W. Donahue, Björn Busse,  Brannon I. Hulsey, Marco Zedda and Scott M.Sorenson

“Studies of secondary osteons in ribs have provided a great deal of what is known about remodeling dynamics. Compared with limb bones, ribs are metabolically more active and sensitive to hormonal changes, and receive frequent low-strain loading. Optimization for calcium exchange in rib osteons might be achieved without incurring a significant reduction in safety factor by disproportionally increasing central canal size with increased osteon size (positive allometry). By contrast, greater mechanical loads on limb bones might favor reducing deleterious consequences of intracortical porosity by decreasing osteon canal size with increased osteon size (negative allometry). Evidence of this metabolic/mechanical dichotomy between ribs and limb bones was sought by examining relationships between Haversian canal surface area (BS, osteon Haversian canal perimeter, HC.Pm) and bone volume (BV, osteonal wall area, B.Ar) in a broad size range of mature (quiescent) osteons from adult human limb bones and ribs (modern and medieval) and various adult and subadult non-human limb bones and ribs. Reduced major axis (RMA) and least-squares (LS) regressions of HC.Pm/B.Ar data show that rib and limb osteons cannot be distinguished by dimensional allometry of these parameters. Although four of the five rib groups showed positive allometry in terms of the RMA slopes, nearly 50% of the adult limb bone groups also showed positive allometry when negative allometry was expected. Consequently, our results fail to provide clear evidence that BS/BV scaling reflects a rib versus limb bone dichotomy whereby calcium exchange might be preferentially enhanced in rib osteons,” (read more/not open access).

(Source: American Journal of Physical Anthropology, in press 2013; top image University of New Mexico)

One of these things is not like the other.

Osteoporosis is a disorder, more common with increased age, in which bone tissue becomes thinner, resulting in brittle bones that are susceptible to breaking.

So, have a glass of milk (rich in vitamin D and calcium–two of the most important nutrients for bone health) while you’re scrolling through your dash today!

Want to learn more about the composition of bone? Click here to read our awesome Compact Bone, Spongy Bone, and Osteons–Oh My!

1. ) Repost, replacing the old information with your muse’s information.
2. ) Hover underlined ‘links’ for better explanations, should you need them.
3. ) Pass it on to your mutuals for a better understanding of their muses.
4. ) Tagged by: @astriferouus​ : D

F A C E.

B A S I C S.

Name. Better known as ‘The Leontyne’ Her human name was Joan Sune.
Age.  Unknown but she has the appearance of 20-25
Gender.  Prefers the pronouns they/them. Close significant others can call her by female pronouns
Nationality.  (When she was human; Persian/Frenchextraterrestrial
Birthplace.  N/A 
Birthday.  N/A
Sun Sign.  N/A
Residence.  Osteon
Marital Status. Single 
Alignment.  N/A

L I K E S.

Drink.  Adice
Food.  She doesn’t have the taste buds humans have. She can only taste organic matter. She loves toxic food so probably scorpions and venomous spiders.
Day or Night.  Night
Snacks.  Anything with poison or venom
Song.  Alti’s notes
Quote: “Eat those who are live to fill the void inside of you.”
Historical Character. N/A
Pet.  Reptiles… Dragons…
Book.  She can only read ancient spells and markings. Beyond that she is illiterate.
Colour.  Black and pearl white probs idk
Flower.  Flowers die in her presence…… offended
Sexuality.  Homo-demiromantic & homosexual

L O O K S.

Body Type.  If her muscles are not tensed, she is roughly 6′2 feet tall. Once she tenses her leg muscles she becomes taller by a few more inches. She has a fair, athletic body. Her skin is usually olive but once exposed to Yuterian snow her skin becomes white and black veins will pop out everywhere, mainly her wrists. 
Eye Colour. Red, gold-ish. Becomes black once exposed to Yuterian skin.
Hair Colour. A very dark brown.
Body reference. N/A
Beauty Scale. 5/7

T A G G I N G.

@ghoulardii@knifethroatedx@caedxs@nullius-amorem​ idk man anyone?? im following like 50 people only and 10 of them are inactive af