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91.
Erwan Messager Aïcha Badou François Fröhlich Brigitte Deniaux David Lordkipanidze Pierre Voinchet 《Archaeological and Anthropological Sciences》2010,2(1):25-34
Mineralised fruits and seeds are frequently found in archaeological sediments but their chemical nature has not been often
examined. The nature and the origin of these archaeobotanical remains have to be investigated to understand their taphonomic
history. Fruits or seeds can be mineralised not only by replacement mineralisation but also by biomineralisation during the
plant life. The mineral components of three fossil fruits sampled on the Pleistocene site of Dmanisi were analysed and compared
with their modern analogues. Analyses were carried out by means of an environmental scanning electron microscope, equipped
with an energy dispersive X-ray device and by means of a Fourier transform infrared spectrometer. Biogenic carbonates and/or
biogenic silica were identified in the fossil and modern fruits of some taxa. Comparison between fossil and modern specimens
has shown that molecular reorganisation occurred in carbonate and in biogenic silica during fossilisation, through diagenetic
processes. The resulting stable mineral structures confer an exceptional preservation to fruits in sediments. Taking into
account these taphonomic specificities (transformation and differential preservation), the chronological and palaeoenvironmental
aspects of the mineralised fruits are discussed. 相似文献
92.
93.
Paul Benneworth Lars Coenen Jerker Moodysson Björn Asheim 《European Planning Studies》2009,17(11):1645-1664
Universities are increasingly seen as potential contributors to regional innovative capacity by serving as local knowledge conduits, bringing global state-of-the-art science and technology into the region. In practice, however, more active university engagement with their regional innovation systems is not as straightforward as it may seem. The article uses examples from a successful case by which less successful regions could be inspired. Our analysis considers how various forms of technological learning intersecting within Lund University around three distinct sectoral engagement efforts have been built up and how this created new structural regional innovation capacity. 相似文献
94.
This article analyses two instances of abortion law reform in Latin America. In 2006, after a decades-long impasse, the highly controversial issue of abortion came to dominate the political agenda when Colombia liberalized its abortion law and Nicaragua adopted a total ban on abortion. The article analyses the central actors in the reform processes, their strategies and the opportunity contexts. Drawing on Htun's (2003) framework, it examines why these processes concluded with opposing legislative outcomes. The authors argue for the need to understand the state as a non-unitary site of politics and policy, and for judicial processes to be seen as a key variable in facilitating gender policy reforms in Latin America. In addition, they argue that ‘windows of opportunity’ such as the timing of elections can be critically important in legislative change processes. 相似文献
95.
Abstract: The state is often described in transition: public spaces are rearranged by private companies, national social welfare is being privatized to some extent, and supranational institutions have more influence on national policies. “A view from the kitchen” (Diane Elson) is helpful for understanding the changing dynamics of states and societies because different women are affected by these policies in different and often ambiguous ways: women of the globalized South migrate to the North, creating global care chains, while women in Western industrialized countries are confronted with changing welfare regimes, leaving mainly highly educated women to profit from this situation. This article contributes to feminist debates on economic globalization and state internationalization. Our feminist materialist perspective allows a critical view on dominance and power in “governance”. Thus, the article adds to feminist debates on globalization from the perspective of state transformation and to debates on governance from the perspective of state transformation grounded in gendered social relations. 相似文献
96.
Detailed cathodoluminescence (CL) imaging of zircon crystals, coupled with Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) U-Pb zircon dating was used to develop new insights into the evolution of granitoids from the High Tatra Mountains. The zircon U-Pb results show two distinct age groups (350±5 Ma and 337±6 Ma) recorded from cores and rims domains, respectively. Obtained results point that the last magmatic activity in the Tatra granitoid intrusion occurred at ca. 330 Ma. The previously suggested age of 314 Ma reflects rather the hydrothermal activity and Pb-loss, coupled with post-magmatic shearing. 相似文献
97.
98.
During the European Bronze Age, flat discs with a variety of decorative elements were produced to be used most likely as either decoration attached to clothing or as parts of horse harnesses. The size and decoration differ according to region and period. The discs discussed here were all found in hoards deposited in a rather short period around 1200–1100?BC in Croatia, Bosnia and Austria. They were analysed to obtain information about their composition and manufacture, both of which may have changed in relation to increasing distance from the centre of distribution or supposed production as a result of copying, or might not have changed significantly if the discs were imported. 相似文献
99.
Helene Brembeck Barbro Johansson Kerstin Bergström Pontus Engelbrektsson Sandra Hillén Lena Jonsson 《Children's Geographies》2013,11(1):74-88
In this article, we discuss children's becoming as food consumers in the intersection of various foodscapes. We draw from a project, Children as co-researchers of foodscapes, where we have been working with children as co-researchers, using basically ethnographic methods, and as co-designers in a collaborative design effort. This article focuses on the findings from a theoretically inspired perspective, using the concept of foodscapes. These are food-related structures of different kinds, which evolve as the child explores them and where children as food consumers are generated. In this article, we highlight the scapes of taste, routines, people, things, commerce, child (as opposed to adult) and health and give brief accounts of the way the children related to them. Finally, we turn to the benefits of working with foodscapes for a better understanding of children's becoming as food consumers in the intersection of various foodscapes. This article is based on data gathered by the children, but also on our fieldwork notes and observations following the children in their foodscapes. 相似文献
100.
Ilana Löwy 《Berichte zur Wissenschaftsgeschichte》2022,45(3):487-498
In 2013, Hans Jörg Rheinberger proposed that Mendelian genetics and molecular biology were “scientific ideologies,” that is, for him they are systems of thought whose objects are hyperbolic; they are not, or not yet, in the realm of and not, or not yet, under the control of that system. This article proposes that precision medicine today is a scientific ideology and analyses the implications of this statement for historians of biology, genetics, and medicine. 相似文献