Fracture In Teeth—A Diagnostic For Inferring Bite Force And Tooth Function,
2011
Biological Sciences
Fracture In Teeth—A Diagnostic For Inferring Bite Force And Tooth Function, Paul J. Constantino, Brian R. Lawn, James J.-W. Lee, Peter W. Lucas
Biological Sciences Faculty Research
Teeth are brittle and highly susceptible to cracking. We propose that observations of such cracking can be used as a diagnostic tool for predicting bite force and inferring tooth function in living and fossil mammals. Laboratory tests on model tooth structures and extracted human teeth in simulated biting identify the principal fracture modes in enamel. Examination of museum specimens reveals the presence of similar fractures in a wide range of vertebrates, suggesting that cracks extended during ingestion or mastication. The use of ‘fracture mechanics’ from materials engineering provides elegant relations for quantifying critical bite forces in terms of characteristic tooth …
Failure To Ubiquitinate C-Met Leads To Hyperactivation Of Mtor Signaling In A Mouse Model Of Autosomal Dominant Polycystic Kidney Disease,
2010
Harvard University
Failure To Ubiquitinate C-Met Leads To Hyperactivation Of Mtor Signaling In A Mouse Model Of Autosomal Dominant Polycystic Kidney Disease, Shan Qin, Mary Taglienti, Surya M. Nauli, Leah Contrino, Ayumi Takakura, Jing Zhou, Jordan A. Kreidberg
Pharmacy Faculty Articles and Research
Autosomal dominant polycystic kidney disease (ADPKD) is a common inherited disorder that is caused by mutations at two loci, polycystin 1 (PKD1) and polycystin 2 (PKD2). It is characterized by the formation of multiple cysts in the kidneys that can lead to chronic renal failure. Previous studies have suggested a role for hyperactivation of mammalian target of rapamycin (mTOR) in cystogenesis, but the etiology of mTOR hyperactivation has not been fully elucidated. In this report we have shown that mTOR is hyperactivated. in Pkd1-null mouse cells due to failure of the HGF receptor c-Met to be properly ubiquitinated and subsequently …
Human Induced Rotation And Reorganization Of The Brain Of Domestic Dogs,
2010
University of Sydney
Human Induced Rotation And Reorganization Of The Brain Of Domestic Dogs, Taryn Roberts, Paul Mcgreevy, Michael Valenzuela
Anatomy Collection
Domestic dogs exhibit an extraordinary degree of morphological diversity. Such breed-to-breed variability applies equally to the canine skull, however little is known about whether this translates to systematic differences in cerebral organization. By looking at the paramedian sagittal magnetic resonance image slice of canine brains across a range of animals with different skull shapes (N = 13), we found that the relative reduction in skull length compared to width (measured by Cephalic Index) was significantly correlated to a progressive ventral pitching of the primary longitudinal brain axis (r = 0.83), as well as with a ventral shift in the position …
Your Attention Please: Increasing Ambient Noise Levels Elicits A Change In Communication Behaviour In Humpback Whales (Megaptera Novaeangliae),
2010
University of Queensland
Your Attention Please: Increasing Ambient Noise Levels Elicits A Change In Communication Behaviour In Humpback Whales (Megaptera Novaeangliae), Rebecca A. Dunlop, Douglas H. Cato, Michael J. Noad
Bioacoustics Collection
High background noise is an important obstacle in successful signal detection and perception of an intended acoustic signal. To overcome this problem, many animals modify their acoustic signal by increasing the repetition rate, duration, amplitude or frequency range of the signal. An alternative method to ensure successful signal reception, yet to be tested in animals, involves the use of two different types of signal, where one signal type may enhance the other in periods of high background noise. Humpback whale communication signals comprise two different types: vocal signals, and surface-generated signals such as ‘breaching’ or ‘pectoral slapping’. We found that …
Hair Whorls In The Dog (Canis Familiaris), Part Ii: Asymmetries,
2010
University of Sydney
Hair Whorls In The Dog (Canis Familiaris), Part Ii: Asymmetries, Lisa M. Tomkins, Paul Mcgreevy
Anatomy Collection
In horses and cattle, hair whorls have been shown to act as a structural marker of reactivity and behavioral lateralization. Few studies on canine whorls have been reported and none have assessed whorl position or direction of flow. This study describes the distribution and characteristics of whorl in each of 10 regions in which whorls are typically located in dogs. Hair whorls were assessed in dogs (n = 120) and were recorded as clockwise or counterclockwise in the cephalic, cervical (dorsal, lateral, ventral), thoracic and brachial axillary, chest, shoulders, elbows, abdominal, and ischiatic regions. Bilateral whorls, including brachial axillary, elbow, …
Hair Whorls In The Dog (Canisfamiliaris). I. Distribution,
2010
University of Sydney
Hair Whorls In The Dog (Canisfamiliaris). I. Distribution, Lisa M. Tomkins, Paul Mcgreevy
Anatomy Collection
Hair whorl characteristics were assessed in the domestic dog (Canis familiaris) in the regions of cephalic, cervical (dorsal, ventral, and lateral), thoracic and brachial axillary regions, the chest, shoulders, elbows, ventral abdominal region, and on the caudal thighs (ischiatic). They were classified as simple or tufted, and their position was recorded as the distance between their centers and bony landmarks within each region. The distribution of whorls was explored in a cohort of domestic dogs (N = 120) comprising a variety of breeds and cross‐breeds, sourced from shelters (N = 60) and the general public (N = 60). …
Different Training Volumes Yield Equivalent Increases In Bmd,
2010
Chapman University
Different Training Volumes Yield Equivalent Increases In Bmd, R. A. Pierce, L. C. Lee, C. P. Ahles, S. M. Shdo, S. V. Jaque, Ken D. Sumida
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The purpose of this study was to determine if an exercise threshold existed in stimulating an elevation in bone mineral density (BMD), via resistance training, during the growth period in male rats. 27 male rats were randomly divided into Control (Con, n = 9), 3 ladder climb resistance trained group (3LC, n = 9), and 6 ladder climb resistance trained group (6LC, n = 9). The 3LC and 6LC groups were conditioned to climb a vertical ladder with weights appended to their tail 3 days/wk for a total of 6 wks, but the 6LC group performed significantly more work than …
Equal Bmd After Daily Or Triweekly Exercise In Growing Rats,
2010
Chapman University
Equal Bmd After Daily Or Triweekly Exercise In Growing Rats, B. D. Kayser, J. K. Godfrey, R. M. Cunningham, R. A. Pierce, S. V. Jaque, Ken D. Sumida
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The purpose of this study was to examine the efficacy of continuous resistance training (3 days/wk) compared to interrupted resistance training where 20-24 h separated an exercise bout (i.e. 6 days/wk) for enhancing bone mineral density (BMD) in growing male rats. The total volume of work performed per week between the two resistance training programs was equivalent by design. Young male rats were randomly divided into Control (Con, n = 9), 3 days/wk resistance trained group (RT3, n = 9), and 6 days/wk resistance trained group (RT6, n = 9). The RT3 and RT6 groups were conditioned to climb a …
