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1.
Examples of early astogeny in the species Carinatocella harmeri (Stach), Costaticella hastata (Busk) and Claviporella aurita (Busk) are discussed. The primary zoid differs in each species and if found fossil, only in C. hastata could this zoid be recognised as a bryozoan fragment. Analogous development in other Bryozoa is discussed.  相似文献   

2.
This article explores aspects of teacher education and outdoor education and their relationship with sustainability education (SE) in Scotland. It considers recent national and international developments in the field and in particular the UNESCO (United Nations Educational, Scientific and Cultural Organization) initiative to ‘re-orient teacher education towards sustainable futures’. The implications of such initiatives in schools and teacher education institutes are discussed in the context of formal provision (e.g. geography) and informal opportunities (e.g. citizenship education, outdoor education). The emphasis is on the Scottish experience with the policy and practice of the School of Education of the University of Edinburgh being discussed as an example in relation to this national and international framework.  相似文献   

3.
This paper sets out to describe the fundamentals of thermoluminescent (TL) dating and to explain the principles of operation of the different methods at present in use. The various complicating factors associated with TL dating are discussed, together with the measures which can be taken to recognize and as far as possible to correct them. Those materials from archaeological contexts which are suitable for dating by the TL technique are described and the criteria for the selection of suitable samples, and the methods of obtaining the desired ancilliary information relating to the environment of the site, are discussed.  相似文献   

4.
The Agnostida are the most important part of the fauna of the Abbey Shales, which is the best-known middle St David's (Middle Cambrian) sequence in Britain. Revision of Illing's (1916) collections allows a correlation of the Paradoxides hicksii fauna with Westergaard's (1946) Ptychagnostus atavus-Tomagnostus fissus Zone, and the Paradoxides davidis fauna with Westergaard's Hypagnostus parvifrons Zone and Ptychagnostus punctuosus Zone (based on the Swedish sequence). A Metadiscus sp. is described. Six species of Condylopygidae are discussed, of which three show a pygidial ‘fringe’. Eleven species of Quadragnostinae, three of Ptychagnostinae (one showing a hypostome), and four of Tomagnostinae (including young growth-stages) are illustrated or discussed. Two species of Diplagnostidae, one species of Phalacroma and two of Phalagnostus are illustrated.  相似文献   

5.
The effects of differential recovery have been documented and discussed for almost a century. Screening experiments using comparative collections are one avenue for understanding recovery bias because they develop expectations about what is likely to be recovered. In this study, modern reference specimens of Pacific Island fish were screened through 1/4 inch (6.4 mm) and 1/8 inch (3.2 mm) mesh. Recovery rates are examined across taxa, body size, and element type. The experimental recovery rates are then compared to those from an archaeological fish assemblage from the Moturakau rockshelter, Aitutaki, Cook Islands, to examine how well the data derived from screening experiments are able to predict archaeological recovery patterns. The experimental data is able to accurately predict the taxa recovered in the Moturakau sample. The impact of differential recovery on a variety of interpretations utilizing archaeological fish remains is then discussed.  相似文献   

6.
As well as providing data on meat yield, avian remains can be expected to give information on seasonality, an important parameter for understanding prehistoric hunting economies. An archaeological survey conducted in the Skyring Sea (Province of Magellan, Chile) between 1992 and 1994 provided bird bone assemblages that have been analysed with this aim in mind, of which 12 are discussed here. Cormorants and steamer ducks constitute 97 per cent of the specimens identified. The proportions of avian remains are compared with the mammals remains, and mostly show a predominance of the former. The status and seasonal distribution of animal resources are discussed in order to understand the motivation for such a specialization on bird hunting, when mammals (Artiodactyls and Pinnipeds) can bring a much higher yield of meat. This nomadic marine economy can best be understood when comparisons are made with other sites from the same cultural area. © 1997 John Wiley & Sons, Ltd.  相似文献   

7.
The ‘improvement’ of sheep (Ovis aries) in southern Britain during the post-medieval period is examined using measurements taken on the metacarpals and metatarsals from the late 18th to 19th centuries AD site of Tumbling Fields, Tiverton, Devon. This data set is a rare and important metric archive from which is derived information on the conformation (size and shape) of sheep. Comparisons are presented from other medieval and post-medieval sites, which demonstrate that Tumbling Fields is comparable to other sites of a similar period. The comparisons presented also reveal temporal variation with bones from later sites being taller and more robust on average than those from earlier sites. In addition, the abnormalities of sheep (O. aries) metapodia are examined. In particular, two different conditions are discussed: small, oval cavities in the proximal articulation of the metacarpals, and a ridge of bone on the proximal anterior shaft of the metatarsals. Comparisons are presented from other medieval and post-medieval sites, and potential aetiologies are discussed.  相似文献   

8.
Particle induced X-ray emission (PIXE) has been used in analysis of ink and paper of the 42-line Bible and other early printed works. Results are reported and their significance discussed.  相似文献   

9.
al-Tikha is a mid to large Umm an-Nar (c. 2700–2000 BC) settlement situated near Rustaq at the back of the Southern Batinah coastal plain in the Sultanate of Oman that was discovered (or rediscovered) in 2014. The site is unique because its layout and spatial organisation are very largely (possibly completely) visible on the surface. This includes two separate areas of stone-built housing, a large pottery scatter of varying density, three or four typical Umm an-Nar round towers and a small cemetery consisting of at least four tombs, along with a few other features. The layout of the site is described and discussed in detail, in particular, in relation to what it might tell us about the nature of Umm an-Nar settlement and social organisation more generally. The location of the site within a pattern of repeating Umm an-Nar settlement along Wadi Far (Wādī al-Farʿī) is also described and discussed.  相似文献   

10.
A review of past industrialization of Siberia and future plans, discussed in terms of three basic zones: (1) the developed belt along the Trans-Siberian Railroad; (2) the southern margins of the tayga immediately to the north of the railroad, and (3) valuable mineral sites selectively developed in the rest of Siberia. Individual industrial nodes are listed and developmental problems outlined.  相似文献   

11.
Morphological distinctions between the mandibular teeth of young sheep (Ovis) and goats (Capra) are described, and their value in the study of bone samples from archaeological sites is briefly discussed.  相似文献   

12.
The total electron content (TEC) of the ionosphere at 31°S (geographic) has been calculated on the basis of Faraday rotation measurements made between September 1967 and January 1975 using geostationary satellites. The day-to-day, diurnal, seasonal and solar cycle variations of TEC are illustrated and discussed in relation to the maximum electron density of the F-layer, NMAX. A regression analysis is used to derive curves corresponding to fixed high and low levels of activity. The variations of slab thickness S = TEC/NMAX are also illustrated and discussed. The results overlap the observation periods of other published results and general agreement is found with these other results.  相似文献   

13.
The palaeontological data on mammal remains from two Middle Palaeolithic (ca. 125 000 years ago – 27 200 BP) and 34 (ca. 34 000–12 000 BP) Upper Palaeolithic cultural complexes in the upper part of the Yenisei River basin (southern Siberia) are considered. General features of the faunal assemblages are established. Several issues are discussed, including (a) changes in species composition through time and palaeoenvironmental implications of the zooarchaeological records; (b) patterns of human exploitation (hunting) of mammals; (c) issue of mammoth hunting and (d) possibility of domestication of dog in the late Upper Palaeolithic in the Yenisei River basin. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

14.
ABSTRACT

Busycon discs, barrels, rings, and columellas, Leptoxis and Prunum shell beads, and stone and coal beads from Webb and Moore excavations at Indian Knoll (15OH2) are discussed in this paper as the author seeks to determine how beads were deployed to convey social information during the Archaic period. After wrestling with the count of beads (ca. 27,337) and the number of burials (ca. 260) with beads, the types of beads are tallied and measurements given based on the author’s examination of beads. The presence and distribution of beads in the shell-bearing stratum and the hardpan, and their distribution among women, men, and subadults, are explored. The beads appear to have been assembled rather than manufactured as sets. An argument is made that shell beads were used at Indian Knoll as regalia for members of and victims of a hunt god/spirit cult. Leptoxis sashes are identified in 36 burials and discussed as regalia. Bead co-occurrence with atlatls, faunal species, and violent death is examined as part of the hypothesized cult rituals.  相似文献   

15.
In a recent paper (Meek, 1980) a fast and efficient method for analysing ionospheric drift records was described. The technique is well suited to real-time analysis.Examples of winds data (60–110 km) obtained from the medium frequency (2.2 MHz) radar at Saskatoon (52°N, 107°W) during 1980 are described here. The quantity and quality of data obtained during typical summer and winter months are discussed. Height time cross-sections of mean winds and tides are also shown.  相似文献   

16.
The economic importance of bone fat to past peoples is discussed and the ethnography of bone marrow and grease extraction is briefly outlined. Models for expected patterns of bone fracture and fragmentation, relating to the exploitation of bone marrow and grease, are described. Current methods for assessing bone fracture and fragmentation, in archaeological assemblages, are discussed and a new methodology is suggested. The importance of retaining and studying the “indeterminate” class of fragments is stressed. The new methodology employs a fracture freshness index (FFI) to study fracture type, and fragmentation is assessed through the separation of fragments into size classes and different bone types. An example application is given.  相似文献   

17.
The analysis of fossil wood fragments is often undertaken in relation to the archaeological excavation of a site. However, such analysis does not yet appear to have the strong methodological foundation that the investigation of many other classes of palaeoenvironmental evidence (e.g. seeds and pollen) have. Consequently, it is difficult to evaluate the value of fossil wood analysis at an archaeological site. Using data regarding non-artifactual wood assemblages at one site in southern Scotland, the relative merits of possible analysis are described and discussed. The results from such analyses tend to fall into two broad groups: (I) those of relatively high reliability, and (2) those of relatively low reliability. The results in the former group are often based on moderately secure methodology and tend to provide relatively non-interpretative information (e.g. species lists). On the other hand, those in the latter group are more often based on insecure interpretive methodology and provide relatively more stimulating information, such as evidence for prehistoric woodland management. There are many reasons for this situation, and these are discussed. In conclusion, it is argued that to increase the reliability of results in the second group (in particular), a full understanding of the taphonomy of non-artifactual fossil wood assemblages is needed, and that once this is available attention can then be paid, as elsewhere in environmental archaeology, to the problems of providing statistically valid samples for analysis.  相似文献   

18.
Increasing pressure on innovativeness and collaboration is supposed to strengthen the importance of geographical proximity in innovation systems. But simultaneously there are 'globalization forces' and information and communication technology (ICT) developments that stress wider contexts and different dependencies to place and distance. With case studies of innovative firms at IDEON Science Park in Lund, the article presents analyses of the importance of proximity, related to the kind of knowledge and collaborative arrangements involved in innovation processes. Scope for 'untraded interdependencies' is discussed as well as the possible ICT impact of these collaborative relations. Argument for a three tier innovation system is put forward and its implications for regional innovation strategies are, concludingly, discussed.  相似文献   

19.
Formulae are derived for the Hough components and the mean rate of solar radiational heating by ozone absorption in the presence of a lower reflecting layer. A model of ozone densities based on observational data is presented for each of the four mid-season months January, April, July and October at heights 0(5)80 km and latitudes 0(15)90°. Diurnal and semi-diurnal components of heating are evaluated for migrating modes and discussed in relation to features of the adopted ozone model. Comparisons are made with earlier evaluations.  相似文献   

20.
It is well recognized that magnetospheric and ionospheric convection play a key role in substorm development. Some characteristic implications of the relationship are reviewed and discussed. Southward turning of the IMF or a sudden magnetospheric compression and the associated effects in the magnetotail lead to enhanced earthward plasma flow and to a gradual growth of the ionospheric DP 2 current system. Ionospheric conductivities are enhanced due to increased (mainly Fermi accelerated) electron precipitation. Finally, after an extensive period of convection growth, plasmas in a confined region of the magnetotail become unstable leading to a substorm onset. Occasionally, the entire magnetosphere may experience continuous stable enhanced convection for several hours (up to 10) without clear signatures of magnetospheric substorm-type processes. Impulsive heated plasma beams are observed in the far magnetotail indicating that powerful acceleration processes are in operation. The DP 2 current system in the ionosphere shows a high constantly disturbed level lasting for several hours. The role of ionospheric Hall and Pedersen conductivities is discussed in detail. Three different time constants (ranging from 1 to 1000 min) are identified in the magnetospheric response to convection changes. It is concluded that changes in the tail configuration are needed to start a substorm. Also different types of precipitation mechanisms are active in connection with the various types of magnetospheric response mechanisms. Similarities are found in the wedge-type field-aligned current generation mechanisms during normal substorms and the prolonged stationary magnetospheric convection cases.  相似文献   

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