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Performance of patients with Korsakoff's syndrome and herpes encephalitis was compared on a retrograde amnesia (RA) test, asking subjects to recall and recognize the definitions of words that had come into the language at different time periods. Performance was also compared on a related test in which participants were asked to produce the words to definitions they were given in free recall and cued recall versions. It was hypothesized that, if the temporal gradient in remote memory results from a shift of information from episodic to semantic memory, then there should be a temporal gradient on these tasks, possibly steeper (i.e., greater relative sparing of early memories) in the patients in the Korsakoff group than in the herpes encephalitis group, who have widespread temporal lobe damage. Furthermore, in comparing semantic and episodic remote memory tests, consolidation theory would predict uniform temporal gradients across such tasks, whereas multiple trace theory would predict a differential pattern. The results showed that patients with Korsakoff's syndrome and patients with herpes encephalitis were significantly impaired across all time periods on the vocabulary tests, with only minimal evidence of temporal gradients, relative to healthy participants, and there was no evidence of a differential pattern of impairment between the two patient groups. Comparison with performance on measures of episodic retrograde amnesia, in which there was a differential pattern of temporal gradient, suggests that the relative preservation of early episodic remote memories in patients with Korsakoff's syndrome does not result from an episodic-to-semantic shift in the quality with which memories are stored. These findings are discussed in relation to existing theories of RA and to the patients' underlying patterns of neuropathology.

This study summarizes a large diverse dataset of methane (CH 4 ) fluxes measured from agricultural sites across the British Isles. A total of 53,976 manual static chamber measurements from 27 different sites were investigated to determine the magnitude of CH 4 fluxes from a variety of agricultural fields across the UK and Ireland. Our study shows that contrary to some studies, agricultural soils (both arable and grassland) are small net emitters of CH 4 rather than sinks.Mean fluxes measured from arable and grassland sites (excluding fertiliser and tillage events) were 0.11 ± 0.06 and 0.19 ± 0.09 nmol m −2 s −1 , respectively, and were not found to be significantly different (Welch t-test, p = 0.17). Using the values reported in this study, we estimate that an annual emission of 0.16 and 0.09 Mt of CO 2 -eq is expected from arable and grassland agricultural soils in the UK and Ireland (comparable to 0.3 and 0.7% of the current annual CH 4 emission inventories, respectively). Where CH 4 uptake occurs in soils, it is negligible compared to expected emissions of the application of animal manures and tillage events, which were both found to significantly increase CH 4 emissions in the immediate few days to months after events. Our study highlights that there are significant differences in CH 4 uptake and emissions between sites, and that these differences are partially the result of the moisture content of the soil (i.e., the aerobic status of the soil). We expect uptake of CH 4 to be more prevalent in drier soils where volumetric water content does not exceed 35% and emissions to be exponentially greater where agricultural fields become waterlogged.