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The collection of modern spatially extensive pollen data are important for the interpretation of fossil pollen diagrams. Such datasets are readily available for percentage data but lacking for pollen accumulation rates (PAR). Filling this gap has been the motivation of the pollen monitoring network, whose contributors monitored pollen deposition in modified Tauber-traps for several years or decades across European latitudes. Here we present this monitoring dataset consisting of 351 trap locations with a total of 2742 annual samples covering the period from 1981 to 2017. This dataset shows that climate parameters correlating with latitude determine pollen productivity. A signal of regional forest cover can be detected in the data, while local tree cover seems more important. Pollen traps situated beyond 200 km of the distribution of the parent tree are still collecting occasional pollen grains of the tree in question. PAR's of up to 30 grains cm-2yr-1 in fossil diagram should therefore be interpreted as long distance transport. Comparisons to fossil data from the same areas show comparable values. Comparisons often demonstrate that similar high values for temperate taxa in fossils sites are found further south or downhill. While modern situations comparable to high PAR values of some taxa (e.g. Corylus) may be hard to find, CO2 fertilization and land use may case high modern PAR's that are not documented in the fossil record. The modern data is now publically available in the Neotoma Paleoecology Database and hopefully serves improving interpretations of fossil PAR data. [ABSTRACT FROM AUTHOR]

The oral and dental health of patients with Parkinson's disease (PD) has not been well documented and the findings are conflicting. Patients with PD were invited to take part in a clinical and radiographic examination together with a comparison control group of persons who were a spouse or family member. Subjects (n = 67) and controls (n = 55) were examined and compared. Subjects with PD had more missing teeth, caries, dental plaque, and poorer periodontal health. Counts of cariogenic bacteria in saliva were significantly higher for subjects with PD. They did not consume more sweets or sugar, did not brush less frequently, used dental floss more than controls, and visited the dentist at least as often. Salivary flow levels were comparable between subjects with PD and controls. The lack of muscular control may explain the poorer oral health of patients with PD. Dentists and patients with PD may be reluctant to embark on complex dental procedures, and this may explain the increased number of missing teeth in persons with PD in this study. [ABSTRACT FROM AUTHOR]

Subfossil pollen from two co-existing Betula species in Iceland, B. nana and B. pubescens, is frequently found in sediments and peat. Interpretation of the findings often depends on the ability to differentiate between the two species according to pollen size and structure. Fresh pollen samples were prepared from 70 individual trees/shrubs which had been identified to species by chromosome number. Grain diameters and pore depths were measured and ratios of grain diameter to pore depth (D/P ratios) were calculated. The mean grain diameters of pollen from diploid B. nana and tetraploid B. pubescens were 20.42 and 24.20 µm, whereas mean pore depths were 2.20 and 2.81 µm respectively. Mean D/P ratios were therefore 9.55 for B. nana and 8.85 for B. pubescens. The difference between species was statistically significant for all three pollen parameters. Grain diameter appeared to be the most useful parameter, as only about 20% of the samples were in the overlapping region of the species distributions. Pollen size (grain diameter) was also positively correlated to tree morphology, which was evaluated using species-specific botanical characters. Pollen samples from different locations/populations in Iceland varied slightly in mean size and ratio. The size difference between pollen of B. nana and B. pubescens in this study is less than other papers have reported, which may be due to the effect of introgressive hybridisation between the two birch species in Iceland. [ABSTRACT FROM AUTHOR]