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Objectives: Vibrational spectroscopy is a valuable tool for the study of burned skeletal remains. Nonetheless, most investigations have been focused on a limited number of samples as well as on faunal bones rather than human bones. Conclusions based on those investigations may lack representativeness, namely about the intrabone, intra- and interskeleton variability of several chemometric indices. We aimed to investigate this issue on a large sample of human bones. Material and Methods: Powder samples were collected from 168 bones from four human skeletons. The sampling targeted 47 long bones, 72 short bones, and 49 tarsal bones as well as different bone regions in a total of 638 powder samples. Bones were experimentally burned in an electric muffle furnace for two hours to maximum temperatures ranging from 400°C to 1000°C. Another 623 burned samples were then collected totaling 1261 samples subjected to FTIR-ATR analysis. The CI, BPI, C/C, and OH/P indices were calculated. Results: An important intrabone, intra- and interskeleton variation was observed, especially for the BPI. The CI, C/C, and OH/P indices revealed much less variation so site-specific sampling may not be as critical in these cases. Clear differences between our results and those from previous investigations were observed, namely on the temperature increment evolution of the CI and C/C indices. Discussion: The relatively large heterogeneity, especially at the intrabone level, is possibly the consequence of microstructural bone differences. The dissimilarities observed between our investigation and other published studies are probably due to the fact that the samples used here came from human rather than faunal bones. Also, our samples were buried previously to the experimental burning so this may also partly explain our contrasting results, since previous research was mostly performed on fresh bone. Future inferences based on vibrational spectroscopy analyses should take into account the possible effect of all these sources. [ABSTRACT FROM AUTHOR]

A series of graves belonging to the Phoenician period were investigated after the campaign excavation of 2007 in the Phoenician-Punic necropolis of Monte Sirai (Carbonia, Sardinia, Italy). One tomb in particular (labelled 252) is presented here because of its uniqueness. Tomb 252 contained the cremated remains of an individual, probably male, and comparison of the excavation records alongside reconstruction of the bone material itself makes clear that the individual was cremated in a prone position. It represents the first case of prone cremation reported in the literature. To investigate whether the temperature of the cremation was homogenous across the entire body, we have conducted a combined physical-chemical analysis using X-ray diffraction spectroscopy and Fourier transform infrared. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives: Stem cell therapies based on differentiation of adult or embryonic stem cells into specialized ones appear to be effective for treating several human diseases. This work addresses the mathematical simulation of proliferation kinetics of stem cells. Materials and methods: Sheep bone marrow mesenchymal stem cells (phenotype characterized by flow cytometry analysis) seeded at different initial concentrations in Petri dishes were expanded to confluence. Sigmoid temporal profiles of total counts obtained through classic haemocytometry were quantitatively interpreted by both a phenomenological logistic equation and a novel model based on a one-dimensional, single-staged population balance approach capable of taking into account contact inhibition at confluence. The models’ parameters were determined by comparison with experimental data on population expansion starting from single seeding concentration. Reliability of the models was tested by predicting cell proliferation carried out starting from different seeding concentrations. Results and discussion: It was found that the proposed population balance modelling approach was successful in predicting the experimental data over the whole range of initial cell numbers investigated, while prediction capability of phenomenological logistic equation was more limited. [ABSTRACT FROM AUTHOR]

Objectives: Heat exposure can lead to apparently random osteometric changes that hinder the application of metric methods used for biological profiling. The impracticality of using objective and burn-specific osteometric methods reduces the chances of establishing the biological profiles of unknown individuals based on their skeletal remains. We investigated the potential of chemometry analysis based on infrared spectroscopy to predict the amount of heat-induced osteometric changes and how this reflected into sex estimation., Material and Methods: Bones from 41 identified adult skeletons (24 females and 17 males with ages between 62 and 90 years old) were experimentally burnt to maximum temperatures ranging from 450°C to 1,100°C (attained after 65 to 240 min). Measurements were taken both before and after each experiment and powder samples were analyzed through FTIR-ATR. Correlations among heat-induced metric changes and chemometric indices (crystallinity index; B-type carbonates; carbonate [A + B] to carbonate B ratio; hydroxyl to phosphate ratio; 630 cm -1 , 1450 cm -1 , 3572 cm -1 , and 3642 cm -1 ) were tested. Significant variables were used to build regression models to predict heat-induced metric change which were then tested on an independent set of samples. Agreement in sex estimation between the pre- and post-burnt samples was also evaluated., Results: All indices were significantly correlated to heat-induced metric changes (α = .01) and the highest correlations were obtained for the 630 cm -1 , 3572 cm -1 , and crystallinity index. We confirmed that regression models based on chemometrics obtained from infrared spectra through FTIR-ATR are better at estimating heat-induced metric changes affecting bone and at sexing remains than other osteometric methods such as those based on correction factors or on metric references specific to calcined bones., Discussion: Regression models avoid the subjectivity associated with the application of other methods. While the latter can be applied only to calcined bones, which is difficult to assess sometimes, regression models can be applied to all bones regardless of their condition. Also, regression models have the advantage of allowing to infer about heat-induced metric change on a case-by-case basis., (© 2020 Wiley Periodicals LLC.)