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71.
The relationship between bone mineral density and archaeological bone survivorship has played a critical role in zooarchaeological and taphonomic studies in recent decades. Numerous studies have suggested that higher-density skeletal element portions survive more frequently than lower-density element portions when archaeological assemblages are affected by some taphonomic processes. Interpretations of density mediated destruction have become commonplace in the archaeological literature, and are often used to explain the absence of certain bone elements and element parts in zooarchaeological assemblages. This study explores the effects of rockfall on bovid elements in varied environmental conditions and the differential survivorship of their element parts, and has implications for understanding the taphonomic processes through which bones are subjected to dynamic loading. Actualistic rockfall experiments conducted on twelve samples of frozen, fresh, and semi-dried bovid bones reveal that the generally low-density epiphyseal ends of bone elements resist fracture and analytical deletion with more frequency than the higher-density diaphyses. This evidence suggests that bone density does not correlate with likelihood of breakage or effective archaeological “destruction” when rockfall and other processes that result in dynamic impact are in action. While this research does not question the relationship between bone mineral density and the likelihood for archaeological survivorship as the result of some taphonomic processes, it presents one specific set of taphonomic processes that result in the differential survivorship of low density bone elements parts and the fragmentation and destruction of higher density element parts. This research presents evidence that shows that dynamic impact is a process capable of fragmenting and sometimes destroying high-density elements while low-density elements survive. 相似文献
72.
D.L. Strusz 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):123-150
The Yarralumla Formation of Canberra has been considered the stratigraphic equivalent of the earliest Ludlovian Yass Formation of the Yass Syncline north of Canberra. The previously unpublished brachiopod fauna of the Yarralumla Formation is fully described; comparison with that of the Yass Formation confirms approximate age equivalence. Of the eleven species, none of which is new, eight also occur in or a little above the Yass Formation. 相似文献
73.
The paper describes the formulation of a non-linear, two-dimensional beam finite element with bending, shear and axial force interaction for the static and dynamic analysis of reinforced concrete structures. The hysteretic behaviour of “squat” reinforced concrete members, in which the interaction between shear and flexural deformation and capacity is relevant for the overall structural performance, is emphasised. The element is of the distributed inelasticity type; section axial-flexural and shear behaviours are integrated numerically along the element length using a new equilibrium-based approach. At section level a “hybrid” formulation is proposed: the axial-flexural behaviour is obtained using the classic fibre discretisation and the plane sections remaining plane hypothesis, the shear response instead is identified with a non-linear truss model and described with a hysteretic stress-strain relationship. The latter contains a damage parameter, dependent on flexural ductility, that provides interaction between the two deformation mechanisms. The element has been implemented into a general-purpose finite element code, and is particularly suitable for seismic time history analyses of frame structures. Analytical results obtained with the model are compared with recent experimental data. 相似文献
74.
Malcolm Macmillan 《Journal of the history of the neurosciences》2013,22(4):297-325
Neurosurgery for the removal of brain tumours based on localising signs is usually dated from the 1884 operation by Bennett and Godlee. However, within weeks of that operation claims were made on behalf of William Macewen, the Glasgow surgeon, to have been the real pioneer of such surgery. According to Macewen's protagonists, he had conducted seven similar operations earlier than Bennett and Godlee and, in a notable 1888 address, Macewen described these seven pre-1884 cases and a number of others operated on after 1884. This paper, which is in two parts, contains an evaluation of the claims made for the priority of Macewen's pre-1884 operations. Part I deals mainly with Macewen's work in fields other than brain surgery that are relevant to it and sets out the facts of the controversy. It begins with a brief biography of Macewen, describes his pioneering work in antiseptic and aseptic surgery, his work on osteotomy and bone regeneration, and his use in brain surgery of the knowledge so gained. Part I concludes with an examination of the battle waged in the newspapers between Macewen's and Bennett's and Godlee's supporters, and of previously unpublished correspondence between Macewen himself, David Ferrier and Hughes Bennett. The primary records of the patients on whom Macewen operated, together with other materials relevant to the controversy, are examined in Part II. 相似文献
75.
Documentation of cutmarks is standard protocol in contemporary zooarchaeology. However, there is currently no consensus about how to best quantify them. This study examines differences in cutmark patterning using two approaches: 1) by means of an experiment, comparing a control cutmark pattern to ten simulated highly fragmented sets of front and rear limbs using %NISPcut as the quantitative unit, and 2) by quantifying an archaeological faunal assemblage using both the number of identifiable specimens (NISP) and the comprehensive minimum number of elements (cMNE). Results reveal significant differences in cutmark patterning between the control set and the simulated fragmented sets. Additionally, the ordinal-scale frequencies of cutmark anatomical portions (proximal, shaft, distal) are inconsistent and fluctuate across the simulated sets. Results of the zooarchaeological analysis show that differences between the two quantification methods are significant. In general, this study suggests that on heavily fragmented assemblages, interpretations of butchering behavior based on cutmark patterning are influenced by the chosen unit of quantification. Overall, using NISP as the quantitative unit provides inconsistent results, whereas, by alleviating the effects of high fragmentation, cMNE is more reliable. 相似文献
76.
M. Lebon I. Reiche J.-J. Bahain C. Chadefaux A.-M. Moigne F. Fröhlich F. Sémah H.P. Schwarcz C. Falguères 《Journal of archaeological science》2010
Diagenetic alteration may limit the potential use of the biogenic composition of fossil bone as a reliable source of information for dietary, environmental and climatic reconstructions. One of the key parameters used to determine the state of preservation of fossil remains is their crystallinity. This can be evaluated by means of infrared spectroscopy, measuring the “splitting factor” (IRSF). However, the crystallinity may fail to describe the extent of chemical and mineralogical changes occurring during fossilization, and cannot be used alone as a reliable indicator of biogenic signal preservation. 相似文献
77.
The fat‐ and nutrient‐rich marrow of animal bones can be extracted using different techniques. Passive hammerstone percussion has been the primary focus of experimental bone breaking and the main analogy to understand archaeological bone breakage. Here, the term ‘passive’ is applied because the bone to be broken passively receives the impact from a hammerstone. In addition to this technique, there is another bone‐breaking method that also requires direct percussion, but in an active way. This method is percussion by ‘batting’, in which the bone is actively hit against an anvil until the bone breaks. This technique has rarely been considered at an experimental level and, therefore, has been omitted in the majority of the archaeological interpretations of faunal assemblages with pre‐use of fire technologies. In this study, we attempt to analytically characterize this type of bone‐breaking technique through a systematic comparison with hammerstone percussion. The applied statistical tests will allow us to distinguish some diagnostic modifications, such as the outlines of the fracture planes and the type of notches or their location with respect to the longitudinal axis of the bone. These features and their proportions allow the consideration of the use of this technique in Pleistocene anthropogenic faunal assemblages. 相似文献
78.
79.
Kristine K. Richter Julie Wilson Andrew K.G. Jones Mike Buckley Nienke van Doorn Matthew J. Collins 《Journal of archaeological science》2011
Fish are a large, highly diverse, and anthropologically important group of vertebrates. However, fish bones are underrepresented in the archaeological literature because they are less stable than those of other taxa and identification of bone to species is often difficult or impossible. We explore a new identification system, ZooMS (Zooarchaeology by Mass Spectrometry), which is based upon protein barcoding. As proteins can be cleaved enzymatically and analyzed by mass spectrometry in a repeatable way, protein barcoding is used widely in microbiological contexts for quick and inexpensive protein identification; mass spectra reflect the differences in protein sequence and can therefore be reproducibly linked to a particular protein or protein fragment. ZooMS uses peptide fingerprinting of bone collagen as a method for rapid identification of archaeological bone. This has involved the identification of masses related to peptides of known sequence. For mammals, sufficient sequence information is available for this approach but for groups, such the teleost fish, species are highly diverse and there are few available collagen sequences. Here we report a preliminary investigation into the identification of fish species by peptide mass fingerprinting that does not require sequence information. Collagen mass spectra are used to identify eight species of bony fishes (Osteichthyes) from four orders: Clupeiformes, Salmoniformes, Gadiformes, and Perciformes. The method is applied to both modern and archaeological fish remains and offers the capacity to identify traditionally unidentifiable fish fragments, thus increasing the Number of Identified Specimens (NISP) and providing invaluable information in specialized contexts. 相似文献
80.
The crystallinity of bone mineral represents an established method of measuring heat-induced change and is of importance to fields including material science, clinical science, anthropology and archaeology. A commonly used technique involves the calculation of the Crystallinity Index (CI) using selected peaks from Fourier Transform Infrared (FTIR) absorbance spectra. However, the choice of peaks has to date not been statistically justified. In this study a novel application of statistical techniques to the FTIR spectra of bone samples burned in the range 100 °C–1100 °C has been used to identify 5 new spectral indices of heat-induced crystallinity change. The validity of the new indices was tested by using a statistical classification model (LDA) to predict the burning temperature of a set of 108 bone samples burned between 100 °C and 1100 °C. A correct classification rate (CCR) of 97.2% was obtained when a combination of 4 indices including the CI was used. This was significantly better than the CCR of 66.7% which was obtained when the CI was used on its own. 相似文献