MicroComputed Tomography (laboratory and synchrotron) of intact archeological human second metacarpal bones and age at death

2021 ◽  
Author(s):  
S. R. Stock ◽  
S. Mays ◽  
G. Turner‐Walker ◽  
C. Soriano
Keyword(s):  
Microcomputed Tomography ◽  
Age At Death ◽  
Metacarpal Bones

Quantification of surface-near porosity in additively manufactured aluminum brackets using X-ray microcomputed tomography

2021 ◽  
Author(s):  
Sascha Senck ◽  
Michael Happl ◽  
Michael Scheerer ◽  
Jonathan Glinz ◽  
Thomas Reiter ◽  
...  
Keyword(s):  
Microcomputed Tomography ◽  
X Ray

scholarly journals Measurement of Inequality and Compression of Mortality in India for 4 Decades: 1970–2015

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 68-68
Author(s):  
Mukesh Parmar
Keyword(s):  
Standard Deviation ◽  
Gini Coefficient ◽  
Age At Death ◽  
Registration System ◽  
Death Rates ◽  
Male And Female ◽  
Inequality Measures ◽  
Sample Registration System ◽  
Dispersion Measures ◽  
Measurement Of Inequality

Abstract The studies relating to measurement of compression of Mortality in India is scarce. Most of the studies relating to mortality in India are focused on either life expectancy, or adult, and child mortality. We have used methods suggested by Kannisto (2000) and Canudos (2008) to measure the compression of mortality phenomenon for India for four decades viz. 1970-2015. Dispersion measures like simple mean, median, modal age at death; and some complicated measures like life disparity, standard deviation above mode, standard deviation in highest quartile, Interquartile range, Gini coefficient, AID and C-family were calculated for India from 1970-2015. We used the age specific death rates from abridged Life tables given by Sample Registration System published by Govt. of India. Our results show that inequality in mortality is decreasing in general but the gap between male and female is increasing. There was an average of three years difference in mean and modal age at death between male females in 2011-15. Overall, mean, median and modal age at death has increased in four decades but other inequality measures like Gini coefficient, AID, Standard deviation (SD) and coefficient of variation has decreased in four decades in India. C50 indicator, which indicates that 50 percent of deaths are happening in that age interval, declined from 26 years to 20 years for males and 27 years to 17 years for females, thus indicating the rate of compression of mortality is higher for females than males in India during 1970-75 till 2011-15.

scholarly journals Metacarpal Bony Dimensions Related to Headless Compression Screw Sizes

2019 ◽  
Vol 12 (S 01) ◽  
pp. S39-S44
Author(s):  
Michael Okoli ◽  
Kevin Lutsky ◽  
Michael Rivlin ◽  
Brian Katt ◽  
Pedro Beredjiklian
Keyword(s):  
Computed Tomography ◽  
Fracture Fixation ◽  
Ct Scans ◽  
Compression Screw ◽  
Metacarpal Head ◽  
Headless Compression Screw ◽  
Metacarpal Bones ◽  
Headless Compression Screws ◽  
The Mean ◽  
Distal Aspect

Abstract Introduction The purpose of this study is to determine the radiographic dimensions of the finger metacarpals and to compare these measurements with headless compression screws commonly used for fracture fixation. Materials and Methods We analyzed computed tomography (CT) scans of the index, long, ring, and small metacarpal bones and measured the metacarpal length, distance from the isthmus to the metacarpal head, and intramedullary diameter of the isthmus. Metacarpals with previous fractures or hardware were excluded. We compared these dimensions with the size of several commercially available headless screws used for intramedullary fixation. Results A total of 223 metacarpals from 57 patients were analyzed. The index metacarpal was the longest, averaging 67.6 mm in length. The mean distance from the most distal aspect of the metacarpal head to the isthmus was 40.3, 39.5, 34.4, and 31 mm for the index, long, ring, and small metacarpals, respectively. The narrowest diameter of the isthmus was a mean of 2.6, 2.7, 2.3, and 3 mm for the index, long, ring, and small metacarpals, respectively. Of 33 commercially available screws, only 27% percent reached the isthmus of the index metacarpal followed by 42, 48, and 58% in the long, ring, and small metacarpals, respectively. Conclusion The index and long metacarpals are at a particular risk of screw mismatch given their relatively long lengths and narrow isthmus diameters.

scholarly journals Osteoconductive Properties of a Volume-Stable Collagen Matrix in Rat Calvaria Defects: A Pilot Study

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 732
Author(s):  
Karol Alí Apaza Alccayhuaman ◽  
Stefan Tangl ◽  
Stéphane Blouin ◽  
Markus A. Hartmann ◽  
Patrick Heimel ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Bone Formation ◽  
Collagen Matrix ◽  
Microcomputed Tomography ◽  
Soft Tissue Augmentation ◽  
Backscattered Electron Imaging ◽  
Quantitative Backscattered Electron Imaging ◽  
Rat Calvaria ◽  
Backscattered Electron ◽  
Electron Imaging

Volume-stable collagen matrices (VSCM) are conductive for the connective tissue upon soft tissue augmentation. Considering that collagen has osteoconductive properties, we have investigated the possibility that the VSCM also consolidates with the newly formed bone. To this end, we covered nine rat calvaria circular defects with a VSCM. After four weeks, histology, histomorphometry, quantitative backscattered electron imaging, and microcomputed tomography were performed. We report that the overall pattern of mineralization inside the VSCM was heterogeneous. Histology revealed, apart from the characteristic woven bone formation, areas of round-shaped hypertrophic chondrocyte-like cells surrounded by a mineralized extracellular matrix. Quantitative backscattered electron imaging confirmed the heterogenous mineralization occurring within the VSCM. Histomorphometry found new bone to be 0.7 mm2 (0.01 min; 2.4 max), similar to the chondrogenic mineralized extracellular matrix with 0.7 mm2 (0.0 min; 4.2 max). Microcomputed tomography showed the overall mineralized tissue in the defect to be 1.6 mm3 (min 0.0; max 13.3). These findings suggest that in a rat cranial defect, VSCM has a limited and heterogeneous capacity to support intramembranous bone formation but may allow the formation of bone via the endochondral route.

scholarly journals Molecular clocks in ancient proteins: Do they reflect the age at death even after millennia?

2021 ◽  
Author(s):  
Nina Sophia Mahlke ◽  
Silvia Renhart ◽  
Dorothea Talaa ◽  
Alexandra Reckert ◽  
Stefanie Ritz-Timme
Keyword(s):  
Protein Degradation ◽  
Forensic Medicine ◽  
Molecular Clocks ◽  
Post Mortem ◽  
Age At Death ◽  
Morphological Examination ◽  
Dental Tissues ◽  
Ancient Proteins ◽  
Age Estimates ◽  
Age At Death Estimation

AbstractAge at death estimation in cases of human skeletal finds is an important task in forensic medicine as well as in anthropology. In forensic medicine, methods based on “molecular clocks” in dental tissues and bone play an increasing role. The question, whether these methods are applicable also in cases with post-depositional intervals far beyond the forensically relevant period, was investigated for two “protein clocks”, the accumulation of D-aspartic acid (D-Asp) and the accumulation of pentosidine (Pen) in dentine. Eight teeth of skeletons from different burial sites in Austria and with post-depositional intervals between c. 1216 and c. 8775 years were analysed. The results of age at death estimation based on D-Asp and Pen in dentine were compared to that derived from a classical morphological examination. Age at death estimation based on D-Asp resulted consistently in false high values. This finding can be explained by a post-mortem accumulation of D-Asp that may be enhanced by protein degradation. In contrast, the Pen-based age estimates fitted well with the morphological age diagnoses. The described effect of post-mortem protein degradation is negligible in forensically relevant time horizons, but not for post-depositional intervals of thousands of years. That means that the “D-Asp clock” loses its functionality with increasing post-depositional intervals, whereas Pen seems to be very stable. The “Pen-clock” may have the potential to become an interesting supplement to the existing repertoire of methods even in cases with extremely long post-depositional intervals. Further investigations have to test this hypothesis.

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