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In 1932 Sherrington and Adrian were awarded the Nobel Prize in Physiology or Medicine "for their discoveries regarding the functions of neurons" and in 1944 Erlanger and Gasser were awarded the same prize "for their discoveries relating to the highly differentiated functions of single nerve fibres." Sherrington made important discoveries on the reflex functions of the spinal cord, formulated the concept of the "synapse," defined the principle of the "final common path," studied "reciprocal innervation" and showed that central inhibition was an active phenomenon. He distinguished three types of receptors: extero-, intero-, and proprioceptive, studied the proprioceptive reflexes in the decerebrate animal and mapped their pathways in the spinal cord. Adrian made fundamental discoveries on the function of single nerve fibers, developed new techniques for the amplification of the weak signals and discovered that increased stimulation resulted in increased frequency of the impulses, the amplitude being unaffected. Erlanger and Gasser introduced the cathode-ray oscillograph and demonstrated the existence of three main groups of nerve fibers, A, B, and C, the conduction velocities of which were in approximately linear relationship with the fiber diameter, the A-fibers being the fastest and thickest and the C-fibers the slowest and having the finest diameter. Together the contributions by the four Laureates paved the way to modern neurophysiology.  相似文献   
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This paper examines the outcome of interregional migration in various aspects from the migrants' perspective. It is based on a survey, including 6 000 interregional migrants in the five Nordic countries. The results indicate that interregional migration leads to a positive outcome for most migrants and few people seem to be forced to make decisions including painful tradeoffs. Motives have an effect on what aspects of outcome migrants are satisfied with. The influence of individual migrants' characteristics on migration outcome revealed few significant effects. Migrants claimed to be most satisfied with living conditions and less satisfied with the livelihood after moving. To be satisfied with social conditions turned out to be crucially important for the general outcome of migration.  相似文献   
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ABSTRACT

School lunch is in general regulated through policies and agendas constituted by the perspectives of adults. In this article, we focus on children’s lived experiences of school lunch with a special emphasis on emotions and how they relate to social and physical dimensions. This study draws on empathy-based stories written by 10–11 year olds (n?=?171) from schools in Sweden. We identified three themes: Interaction and exposure, Routines and restrictions and Food and eating. The children’s lived experiences of school lunch and the emotions attached to them are closely associated and intertwined with the socio-spatial dimension of school lunch. A pleasant meal experience seems to require harmonization between the physical and social space whilst negative experiences contain tensions between them, something that actors working with school lunch and school lunch environments should take in consideration when resourcing, planning and scheduling school lunch, and also when designing new school restaurants.  相似文献   
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Written sources from the period of tetrarchy contain information on the political use and abuse of imperial images and other media. This information makes it possible to point out methods and techniques for the use of these media, and thereby to demonstrate some of their functions in political and religious disputes in the Tetrarchic period.  相似文献   
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The historical Norberg mining district in central Sweden with its shallow, easily accessible iron ores figures prominently in the earliest documents from the 14th century concerning mining or metallurgy. This 1000-km2 district is considered to be one of the first areas in Sweden exploited for iron ores and, in fact, Europe’s oldest known blast furnace, Lapphyttan, is located in the Norberg district about 10 km from the mines in the village of Norberg (Norbergsby). Earlier archaeological excavations suggest the furnace was in operation as early as the 11th or 12th century (870 and 930 14C yr BP), and a number of other sites in the district have been dated to the 13th–15th centuries. Here, we have analyzed two lake sediment records (Kalven and Noren) from the village of Norberg and a peat record from Lapphyttan. The Lapphyttan peat record was radiocarbon dated, whereas the sediment from Kalven is annually laminated, which provides a fairly precise chronology. Our pollen data indicate that land use in the area began gradually as forest grazing by at least c. AD 1050, with indications of more widespread forest disturbance and cultivation from c. 1180 at Lapphyttan and 1250 at Kalven. Based on 206Pb/207Pb isotope ratios in Kalven’s varved sediment record, there is an indication of mining or metallurgy in the area c. 960, but likely not in immediate connection to our sites. Evidence of mining and metallurgy increases gradually from c. 1180 when there is a decline in 206Pb/207Pb ratios and an increase in charcoal particles at Lapphyttan, followed by increasing inputs of lithogenic elements in Noren’s sediment record indicating soil disturbance, which we attribute to the onset of mining the iron ore bodies surrounding Noren. From AD 1295 onwards evidence of mining and metallurgy are ubiquitous, and activities accelerate especially during the late 15th century; the maximum influence of Bergslagen ore lead (i.e., the minimum in 206Pb/207Pb isotope ratios) in both Kalven and Noren occurs c. 1490–1500, when also varve properties change in Kalven and in Noren sharp increases occur in the concentrations of a range of other ore-related metals (e.g., arsenic, cadmium, copper, iron, lead, mercury and zinc). From the 15th century onwards mining and metallurgy are the dominant feature of the sediment records.  相似文献   
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