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  • 1
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    La Sassa cave: Isotopic evidence for Copper Age and Bronze Age population dynamics in Central Italy (2023)
    Public Library of Science
    Details
    Publication Date: 2023-08-29
    Description: This study focuses on the changes in diet and mobility of people buried in the La Sassa cave (Latium, Central Italy) during the Copper and Bronze Ages to contribute to the understanding of the complex contemporary population dynamics in Central Italy. To that purpose, carbon and nitrogen stable isotope analyses, strontium isotope analyses, and FT-IR evaluations were performed on human and faunal remains from this cave. The stable isotope analyses evidence a slight shift in diet between Copper and Bronze Age individuals, which becomes prominent in an individual, dating from a late phase, when the cave was mainly used as a cultic shelter. This diachronic study documents an increased dietary variability due to the introduction of novel resources in these protohistoric societies, possibly related to the southward spread of northern human groups into Central Italy. This contact between different cultures is also testified by the pottery typology found in the cave. The latter shows an increase in cultural intermingling starting during the beginning of the middle Bronze Age. The local mobility during this phase likely involved multiple communities scattered throughout an area of a few kilometers around the cave, which used the latter as a burial site both in the Copper and Bronze ages.
    Description: Published
    Description: e0288637
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: 6SR VULCANI – Servizi e ricerca per la società
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: JCR Journal
    Keywords: La Sassa cave (Central Italy) ; population dynamics ; nitrogen isotope ; strontium isotope
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
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  • 2
    Electronic Resource
    Electronic Resource
    A two-stage model of fracture of rocks (1996)
    Springer
    Pure and applied geophysics 146 (1996), S. 253-263 
    Details
    ISSN: 1420-9136
    Keywords: Fracture ; fault nucleation ; critical crack density ; hierarchic failure ; earthquakes ; thermal activation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract In this paper we propose a two-stage model of rock fracture. In the first stage, cracks or local regions of failure are uncorrelated and occur randomly throughout the rock in response to loading of pre-existing flaws. As damage accumulates in the rock, there is a gradual increase in the probability that large clusters of closely spaced cracks or local failure sites will develop. Based on statistical arguments, a critical density of damage will occur where clusters of flaws become large enough to lead to larger-scale failure of the rock (stage two). While crack interaction and cooperative failure is expected to occur within clusters of closely spaced cracks, the initial development of clusters is predicted based on the random variation in pre-existing flaw populations. Thus the onset of the unstable second stage in the model can be computed from the generation of random, uncorrelated damage. The proposed model incorporates notions of the kinetic (and therefore time-dependent) nature of the strength of solids as well as the discrete hierarchic structure of rocks and the flaw populations that lead to damage accumulation. The advantage offered by this model is that its salient features are valid for fracture processes occurring over a wide range of scales including earthquake processes. A notion of the rank of fracture (fracture size) is introduced, and criteria are presented for both fracture nucleation and the transition of the failure process from one scale to another.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00876492
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  • 3
    Electronic Resource
    Electronic Resource
    Effect of local application of fluoride on healing of experimental bone fractures in rabbits (1977)
    Springer
    Calcified tissue international 22 (1977), S. 297-302 
    Details
    ISSN: 1432-0827
    Keywords: Fluoride ; Gelfoam ; Fracture ; Ossification ; Breaking force
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract The effect of local application of low fluoride concentrations on the healing of experimental bone-radii fractures in 20 rabbits was examined. No external fixation was required after the osteotomy and gelfoamℜ being used as a medium for fluoride application. Histologic mineral and mechanical strength measurements were carried out on the healing callus. There were no significant changes in the ashpercentage and the fluoride concentration of the ash between the experimental and control callus. A significantly higher percentage of ossified tissue was found in the fluoride treated callus. The breaking strength was found to be significantly higher in the bone fractures treated with fluoride, whereas there was no notable difference between the surface areas. It is postulated that the greater amount of ossified tissues, the differences in organization of the bone trabecules, and/or an improved mineral crystallinity may be responsible for this result.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02010368
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  • 4
    Electronic Resource
    Electronic Resource
    Uptake of47Ca and85Sr in the tibia and the femur in rats (1969)
    Springer
    Calcified tissue international 3 (1969), S. 96-99 
    Details
    ISSN: 1432-0827
    Keywords: Calcium metabolism ; Strontium metabolism ; Fracture ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La relation entre la résorption du85Sr et du47Ca était mesuré au tibia et fémur des rats 24 heures après l'injection. La différence entre les manches et les bouts était, remarquable, mais pas entre les os séparates; en les tibiae, qui etait fracturé depuis 7 semaines et guéries, la relation etait identique à celui des tibiae manches normals. On a présumé que la découverte était due à des différences qualitatives plustot que quantitatives entre les procédé de minéralisation dans l'os cortical et trabeculair.
    Abstract: Zusammenfassung Das Verhältnis zwischen der Abnahme von85Sr und47Ca wurde von der Tibia und Femur 24 Std nach der Injektion bei Ratten gemessen. Man fand einen signifikanten Unterschied zwischen den Schaften und den Enden, aber nicht zwischen den verschiedenen Knochen. In 7 Wochen alten, verheilten Tibiafrakturen war das Verhältnis genau so wie in einem normalen Tibiaschaft. Das Resultat berechtigte zu der Annahme, daß der Unterschied in dem Mineralisierungsprozeß zwischen corticalen und spongiösen Knochen wahrscheinlich qualitativ und nicht quantitativ ist.
    Notes: Abstract The ratio between the uptake of85Sr and47Ca was measured in the tibiae and femora of rats 24 h after injection of the tracers. There was a significant difference between shafts and ends but not between the different bones; in healed tibial fractures, 7 weeks old, the ratio was identical to that of normal tibial shafts. The findings were interpreted to be related to qualitative rather than quantitative differences in mineralization between cortical and trabecular bone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02058650
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  • 5
    Electronic Resource
    Electronic Resource
    Delayed fracture healing following jejunoileal bypass surgery for obesity (1982)
    Springer
    Calcified tissue international 34 (1982), S. 13-15 
    Details
    ISSN: 1432-0827
    Keywords: Fracture ; 1,25-Dihydroxycholecalciferol ; 25-Hydroxycholecalciferol ; Jejunoileal bypass ; Obesity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A 38-year-old woman, who 5 years earlier had undergone a jejunoileal bypass for gross obesity, fractured the distal forearm by a minor trauma. Circulating 25-hydroxycholecalciferol was undetactable without vitamin D3 supplement but increased to the lower normal range on a daily dose of 1200 units of vitamin D3. Serum 1,25-dihydroxycholecalciferol was, however, in the upper normal range, both without and with vitamin D supplement. After intestinal reanastomosis the fracture healed and the biochemical changes normalized. Malabsorption due to reduced amount of functioning intestine may cause severe metabolic bone disease, which may not always be reverted by a high-calcium diet and vitamin D supplementation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411201
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  • 6
    Electronic Resource
    Electronic Resource
    Videodensitometry of osteons in females with femoral neck fractures (1993)
    Springer
    Calcified tissue international 52 (1993), S. 273-277 
    Details
    ISSN: 1432-0827
    Keywords: Bone density ; Bone mineral ; Porosity ; Fracture ; Osteon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The medial femoral cortices of 10 females with femoral neck fractures and 10 age-matched female autopsy cases were studied using computer-assisted videodensitometry. Radiographic mineral density was determined using the calibration method described by Martin et al. [20]. Measurements were made of porosity, osteon and haversian canal dimensions, and of interstitial and osteon mineral density across the cortical wall of the orthopedic calcar region. There were no differences between the fracture and nonfracture groups in the overall mean mineral density of the bone averaged over the microstructure, excluding pore space, or in the interstitial bone mineral density. The porosity in the fracture group was greater than in the autopsy group, especially in the periosteal region, where the porosity was 2.4 times greater and where there were also 27% fewer osteons per unit area than in the autopsy group (P〈0.05). Mean osteon mineral density was 2.5% higher in the fracture group (P〈0.05) compared with the autopsy group in the endosteal region, and 4% higher in the periosteal region. Osteon and haversian canal areas were also larger in the fracture group, especially in the middle region of the cortical wall (17% and 23%, respectively, P〈0.05).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00296651
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  • 7
    Electronic Resource
    Electronic Resource
    Insulinlike growth factor gene expression in human fracture callus (1993)
    Springer
    Calcified tissue international 53 (1993), S. 97-102 
    Details
    ISSN: 1432-0827
    Keywords: Insulinlike growth factor ; Fracture ; In situ hybridization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The effects of insulinlike growth factors on bone and cartilage-derived cells in culture have been extensively investigated, but there is little information on their rolein vivo in bone, especially in fracture healing. This study investigated insulinlike growth factor (IGF) I and II mRNA expression in normally healing human fractures byin situ hybridization. Endothelial and mesenchymal cells at the granulation tissue stage expressed IGF-II mRNA. At the stage of bone and cartilage formation, osteoblasts and nonhypertrophic chondrocytes expressed mRNA for both IGF-I and II. Some osteoclasts were positive for IGF-II mRNA at the stage of bone remodeling. The greater time span of IGF-II expression relative to IGF-I reflects the predominance of IGF-II in human bone matrix. Taken together with the known effects of IGFs on bone and cartilage cellsin vitro, these findings support a role for IGFs in local cellular regulation in human fracture healing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01321886
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  • 8
    Electronic Resource
    Electronic Resource
    Clinical determination of bone quality: Is ultrasound an answer? (1993)
    Springer
    Calcified tissue international 53 (1993), S. S151 
    Details
    ISSN: 1432-0827
    Keywords: Ultrasound ; Bone fragility ; Osteoporosis ; Fracture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Progress in clinical characterization of bone relies on developing a means to clinically assessall of the important determinants of bone quality, specifically, the intrinsic material properties of a bone (stiffness and brittleness) versus the macroscopic structural properties [apparent mass density (g/cc), structural shape and distribution of cortical mass, trabecular architecture, extent of unrepaired microdamage, and defects associated with the accelerated remodeling in early menopause]. Ultrasound devices currently measure parameters related to either of only two basic properties: bone ultrasound attenuation (BUA) or the apparent velocity of wave propagation (AVU). Theory and repeated corroboration in the laboratory have shown that the velocity of sound in solids such as bone has a quantitative relationship to the elastic modulus (or stiffness) and mass density. Although no comparable physical model exists for BUA, growingin vitro andin vivo empirical evidence shows a relationship to stiffness and mass density as well. Therefore, the question of ultrasound's ability to provide additional, clinically useful information about bone quality reduces to this:Does bone quality depend significantly on bone stiffness and does stiffness depend on factors other than bone mass alone? Clinical study results provide mounting evidence of ultrasound's abilities. (1) Numerous studies compare either velocity or BUA with BMC or BMD. The correlation coefficients vary widely between studies, even when repeated by the same investigators and laboratories. Two studies demonstrated this by comparing groups of subjects who are indistinguishable by BMD at the lumbar spine, but whose mean AVU readings are significantly different. (2) Multiple studies of AVU and BUA by different investigators have shown the ability of ultrasound to distinguish, as effectively as BMC or BMD, women with osteoporotic vertebral crush deformities from normal women. Prospective studies have shown that AVU and BUA each indicated risk of future osteoporotic fractures. In a population-based, randomized, cross-sectional study of men and women, AVU discriminated between groups of subjects who had suffered low trauma fractures versus those free of fracture. Such repeated clinical evidence of the ability of BUA and AVU to detect bone fragility provides mounting evidence that ultrasound measures a clinically relevant property of bone quality in addition to and distinct from bone mass.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01673427
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  • 9
    Electronic Resource
    Electronic Resource
    Risk analysis of fracture and failure (1998)
    Springer
    Materials research innovations 2 (1998), S. 16-21 
    Details
    ISSN: 1433-075X
    Keywords: Key words Risk ; Reliability ; Fracture ; Failure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract  This paper is inspired by the work of Professors Heinz Wilsdorf and Doris Kuhlmann-Wilsdorf on fundamental aspects of ductile fracture mechanism. Risk – a measure of the probability and severity of adverse effects – is introduced and related to the consequences associated with elastic (reversible) deformation, plastic (irreversible) deformation, and catastrophic deformation (total failure). Cost-benefit-risk trade-off analysis is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100190050055
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  • 10
    Electronic Resource
    Electronic Resource
    Self organising maps for the investigation of clinical data: A case study (1998)
    Springer
    Neural computing & applications 7 (1998), S. 65-70 
    Details
    ISSN: 1433-3058
    Keywords: Data visualisation ; Decision support ; Fracture ; Neural networks ; Osteoporosis ; Self-organising maps
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract The clinical process often involves comparisons of how one set of measurements is related to previous, similar, data and the use of this information to take decisions concerning possible courses of action, often with insufficient data to make meaningful calculations of probabilities. Self-organising maps are useful devices for data visualisation. To illustrate how visualisation with self-organising maps might be used in the clinical process, this paper describes the investigation of an osteoporosis data set using this technique. The data set had previously been used to show that backpropagation neural networks were capable of distinguishing between patients who had suffered a fracture, and those who had not using measured bone mineral density values; illustrating the power of these networks to model relationships in data. However, we had realised that this was somewhat of an academic exercise given that in reality a non-fracture case might be a fracture case waiting to happen. We felt it would be more productive to examine the data itself rather than model an imposed classification. As part of this investigation, the data set was examined using self-organising maps. From the results of the investigation, we conclude that it is possible to create a map, a compressed data representation, using BMD values which may then be partitioned into low and high fracture risk areas. Using such a map may be a useful screening mechanism for detecting people at risk of osteoporotic fracture.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01413710
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