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81.
The nature of long bone formation and the pathways of interaction between bone samples and the burial environment suggest that portions of the bones disconnected from the arterial system are resistant to diagenetic alteration. Preliminary work on femurs from Early Bronze Age hunter-gatherers in Cis-Baikal, Siberia shows that the nature and progression of chemical changes in the bone matrix due to microbial attack can be analyzed using laser ablation inductively coupled plasma mass spectrometry. Intra-osteon variability in elemental concentrations and strontium isotope ratios (87Sr/86Sr) indicate the presence of unaltered portions of bone within diagenetically modified bone and suggest that useful data remain accessible. These biogenic signals can potentially be useful for mobility research in broad terms and the smaller timescales within an individual's lifetime (months, years), accessible therein. Laser ablation micro-sampling of femur specimens showed that intra-osteon elemental composition of Ba, Re, and Cs varied within and was correlated between multiple osteons of a single bone. Portions of chemically unaffected bone were identified within, and effectively discriminated from diagenetically altered bone tissue. Areas showing visual alterations and erratic or uncorrelated Ca and Sr elemental results also had anomalous Sr isotope ratios, suggesting diagenetic alteration in those places. Compositional and isotopic analysis of intact portions of bone supports the hypothesis that hunter-gatherer groups in Cis-Baikal made numerous major movements during their lives. Microscopic analysis of long bones clarifies aspects of biodeterioration and correlations between trace elemental results and diagenetic alteration. Micro-sampling of intact portions of bone expands the scope of available materials for research on mobility and other aspects of human past behavior. 相似文献
82.
Taphonomy of Corumbella werneri from the Ediacaran of Brazil: sinotubulitid tube or conulariid test?
Detlef Hans-Gert Walde Bernd Weber Bernd- D. Erdtmann 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):335-350
Walde, D.H.-G., Weber, B., Erdtmann, B.-D. & Steiner, M. 20 June 2019. Taphonomy of Corumbella werneri from the Ediacaran of Brazil: sinotubulitid tube or conulariid test? Alcheringa 43, 335–350. ISSN 0311-5518The problematic late Ediacaran tubular fossil Corumbella werneri is revised based on two-dimensional compressions, and new three-dimensionally preserved specimens from the Tamengo Formation of the Corumbá Region in Mato Grosso do Sul, west-central Brazil. These fossils represent some of the oldest skeletonized metazoans and were originally described from diagenetically compacted tubes that prompted conflicting interpretations as either Ediacaran coronate scyphozoan exoskeletons, or conulariid tests. Our new material from Corumbá permits a morphological and taphonomic revision of C. werneri, which we suggest was probably a calcareous sinotubulitid. Corumbella werneri closely resembles the late Ediacaran Sinotubulites from South China, as well as the Silurian worm tube Eoalvinellodes, which has similar exterior ornamentation. Ultrastructurally, the tubes of C. werneri exhibit a coarse sparitic microtexture, which we attribute to diagenetic alteration. Partial flexibility also supports interpretation as an originally weakly calcified, or entirely organic exoskeleton. We therefore reject placement of C. werneri as a conulariid scyphozoan, and instead, advocate possible relationships with marine annelids.Detlef Hans-Gert Walde [walde. detlef@gmail. com], University of Brasília, Institute of Geosciences, Brasília-DF, Brazil; Bernd Weber [bweber@zedat. fu-berlin. de], Freie Universität Berlin, Institut für Geologische Wissenschaften, Malteserstr. 74–100, D-12249 Berlin, Germany; Bernd-D. Erdtmann [berni1739@gmail. com], 1165 N Mountain View Road, Apache Junction, AZ 85119, USA; *Michael Steiner [Michael. Steiner@FU-Berlin. de], Freie Universität Berlin, Institut für Geologische Wissenschaften (Haus D), Malteserstr. 74–100, D-12249 Berlin, Germany. 相似文献
83.
84.
This paper is an attempt at defining the social functions of the unchambered megalithic long barrows found in the ?upowa group of the Funnel Beaker Culture (TRB). The authors assume that their aim can be achieved by employing a cultural ecological approach, which leads to a determination of the following variables: exploitation efficiency of the local population, local territory, and size of that population. The values determined for these variables imply that only a small, limited number of the deceased members of the group were buried in the long barrows discussed. Thus, it is possible that burial functions were not the only and most important ones. The authors try to define the remaining functions of the long barrows. 相似文献
85.
Bernd Mielke 《Standort - Zeitschrift für angewandte Geographie》2006,30(1):32-35
Abstrakt Warum ein Blick in die Niederlande? Die Raumplanung in den Niederlanden mit ihrem konzeptionell anspruchsvollen, umsetzungsorientierten
und partizipativem Herangehen galt in Deutschland über viele Jahre als Vorbild. So wurde im 2001 erschienenen „Landesplanungsbericht“
der Staatskanzlei NRW die Innovationsfreudigkeit und Entwicklungsorientierung der niederl?ndischen Raumplanung hervorgehoben
und vorgeschlagen, das niederl?ndische Planungssystem nordrhein-westf?lisch zu „spiegeln“. 相似文献
86.
Wolfhard Weber 《Berichte zur Wissenschaftsgeschichte》2005,28(1):5-94
This compilation of German research in history of science, technology, and medicine for the years 1997 to 2004 will continue the previous ones. Researchers of the institutions have given us these information, however, only up to ten indications were requested by the national committee of the IUHPS/DHS. More research results may be found on the homepages of the larger institutes and of most of the individual researchers. The list adheres to the alphabet of the authors names, no longer to that of the institutions. After this note you will find the survey of them. A new national data base is proceeding very slowly and completion might still last some time in a country where this kind of research is considered to be of regional importance only …! This compilation was again supported by the national German science foundation (DFG), which we appreciated very much. The compilation work was mainly done thanks to the efforts of Verena Witte MA, Bochum. 相似文献
87.
Edward P. Weber 《政策研究杂志》1998,26(1):185-195
Jeanne W. Clarke and Daniel McCool, Staking Out the Terrain : Power and Performance Among Natural Resource Agencies (2nd 4.).
Larry S. Luton, The Politics of Garbage : A Community Perspective on Solid Waste Policy Making.
Peter J. May, Raymond J. Burby, Neil J. Ericksen, John W. Handmer, Jennifer E. Dixon, Sarah Michaels, and D. Ingle Smith, Environmental Management and Governance: Intergovernmental Approaches to Hazards and Sustainability . 相似文献
Larry S. Luton, The Politics of Garbage : A Community Perspective on Solid Waste Policy Making.
Peter J. May, Raymond J. Burby, Neil J. Ericksen, John W. Handmer, Jennifer E. Dixon, Sarah Michaels, and D. Ingle Smith, Environmental Management and Governance: Intergovernmental Approaches to Hazards and Sustainability . 相似文献
88.
In this paper we present a procedure for estimating small changes in gravity model forecasts in response to small changes in input values (trip end totals and/or parameter values). The procedure can be used to derive covariance matrices from which confidence intervals may be obtained and which may be used for tests of hypotheses. While this type of problem has been addressed by others, our approach is the only one that is conveniently applicable to the doubly constrained model and can accommodate the large numbers of origin and destination zones one typically encounters. 相似文献
89.
János Jakucs Eszter Bánffy Krisztián Oross Vanda Voicsek Christopher Bronk Ramsey Elaine Dunbar Bernd Kromer Alex Bayliss Daniela Hofmann Peter Marshall Alasdair Whittle 《Journal of World Prehistory》2016,29(3):267-336
Perhaps nowhere in European prehistory does the idea of clearly-defined cultural boundaries remain more current than in the initial Neolithic, where the southeast–northwest trend of the spread of farming crosses what is perceived as a sharp divide between the Balkans and central Europe. This corresponds to a distinction between the Vin?a culture package, named for a classic site in Serbia, with its characteristic pottery assemblage and absence of longhouses, and the Linearbandkeramik (LBK), with equally diagnostic but different pottery, and its apparently culturally-diagnostic longhouses, extending in a more northerly belt through central Europe westward to the Dutch coast. In this paper we question the concept of such a clear division through a presentation of new data from the site of Szederkény-Kukorica-d?l?. A large settlement in southeast Transdanubia, Hungary, excavated in advance of road construction, Szederkény is notable for its combination of pottery styles, variously including Vin?a A, Ra?i?te and LBK, and longhouses of a kind otherwise familiar from the LBK world. Formal modelling of its date establishes that the site probably began in the later 54th century cal BC, lasting until the first decades of the 52nd century cal BC. Occupation, featuring longhouses, pits and graves, probably began at the same time in the eastern and western parts of the settlement, starting a decade or two later in the central part; the western part was probably the last to be abandoned. Vin?a pottery is predominantly associated with the eastern and central parts of the site, and Ra?i?te pottery with the west. Formal modelling of the early history of longhouses in the LBK world suggests their emergence in the Formative LBK of Transdanubia c. 5500 cal BC followed by rapid dispersal in the middle of the 54th century cal BC, associated with the ‘earliest’ (älteste) LBK. The adoption of longhouses at Szederkény thus appears to come a few generations after the start of this ‘diaspora’. Rather than explaining the mixture of things, practices and perhaps people at Szederkény with reference to problematic notions such as hybridity, we propose instead a more fluid and varied vocabulary, encompassing combination and amalgamation, relationships and performance in the flow of social life, and networks; this makes greater allowance for diversity and interleaving in a context of rapid change. 相似文献
90.
Bernd Holdorff 《Journal of the history of the neurosciences》2016,25(1):63-71
Tonic neck reflexes were investigated by Rudolf Magnus and Adriaan de Kleijn in animals and men in 1912 and eventually by Arthur Simons, a neurologist in Berlin and coworker of Hermann Oppenheim. Simons studied these reflexes in hemiplegic patients, who were mainly victims of World War I. This work became his most important contribution and remained unsurpassed for many years. The film (Filmarchiv, Bundesarchiv [Film Archive, National Archive] Berlin) with Simons as an examiner shows 11 war casualties with brain lesions that occurred between 1916 and 1919. The injuries reveal asymmetric neck reflexes with “Mitbewegungen,” that is, flexion or extension on the hemiplegic side. Mitbewegungen is identical with Francis Walshe’s “associated reactions” caused by neck rotation and/or by cocontraction of the nonaffected extremities, for example, by closing of the fist (Walshe). The knowledge of the neck reflexes is important in acute neurology and in rehabilitation therapy of hemiplegics for antispastic positions. Simons’ investigations were conducted in the early era of increasing use of cinematography in medical studies. The film had been nearly forgotten until its rediscovery in 2010. 相似文献