The geomorphology of the Ochil Hills

The Ochil Hills, running northeastwards from the Forth at Stirling, to Tentsmuir on the North Sea coast, are the most Impressive and most extensive of the several uplands which diversify the Central Lowlands of Scotland (Fig. 1). Separating Strathmore from the coalfields and agricultural lowlands of Clackmannan, Kinross and Fife, for much of their length they offer a formidable barrier to north-south communications, only two really good roads crossing them in a distance of some twenty-five miles. In the west, the hills rise from the flat, near sea-level carselands of the Devon in one of the most magnificent escarpments in Britain, reaching heights of 1,600- 1700 ft. above sea-level in one unbroken slope (Photographs 1 and 2). In the east, beyond Glen Parg, they deteriorate into a "tail" of low, isolated hills: this area has not been included in the present study. The width of the range varies, from ten miles in the west, to less than five in the east. In the west are the highest summits, culminating in Bencleuch at 2,363 ft. O.D., and enclosing the deep valley of Glen Devon. Further east, although the Water of May occupies a deep, longitudinal valley, there is no development of an independent drainage system comparable to that of the Devon and its tributaries, and the hills became a relatively simple divide between drainage to the Earn and to the Firth of Forth

Criticism of the Use of Coomassie Brilliant Blue G-250 for the Quantitative Determination of Proteins

Peer Reviewe

Darwin’s wind hypothesis: does it work for plant dispersal in fragmented habitats?

Using the wind-dispersed plant Mycelis muralis, we examined how landscape fragmentation affects variation in seed traits contributing to dispersal. Inverse terminal velocity (Vt−1) of field-collected achenes was used as a proxy for individual seed dispersal ability. We related this measure to different metrics of landscape connectivity, at two spatial scales: in a detailed analysis of eight landscapes in Spain and along a latitudinal gradient using 29 landscapes across three European regions. In the highly patchy Spanish landscapes, seed Vt−1 increased significantly with increasing connectivity. A common garden experiment suggested that differences in Vt−1 may be in part genetically based. The Vt−1 was also found to increase with landscape occupancy, a coarser measure of connectivity, on a much broader (European) scale. Finally, Vt−1 was found to increase along a south–north latitudinal gradient. Our results for M. muralis are consistent with ‘Darwin’s wind dispersal hypothesis’ that high cost of dispersal may select for lower dispersal ability in fragmented landscapes, as well as with the ‘leading edge hypothesis’ that most recently colonized populations harbour more dispersive phenotypes.

Weak negative associations between avian influenza virus infection and movement behaviour in a key host species, the mallard Anas platyrhynchos

Animal movements may contribute to the spread of pathogens. In the case of avian influenza virus, [migratory] birds have been suggested to play a role in the spread of some highly pathogenic strains (e.g. H5N1, H5N8), as well as their low pathogenic precursors which circulate naturally in wild birds. For a better understanding of the emergence and spread of both highly pathogenic (HPAIV) and low pathogenic avian influenza virus (LPAIV), the potential effects of LPAIVs on bird movement need to be evaluated. In a key host species, the mallard Anas platyrhynchos, we tested whether LPAIV infection status affected daily local ( 100 m) movements by comparing movement behaviour 1) within individuals (captured and sampled at two time points) and 2) between individuals (captured and sampled at one time point). We fitted free-living adult males with GPS loggers throughout the autumn LPAIV infection peak, and sampled them for LPAIV infection at logger deployment and at logger removal on recapture. Within individuals, we found no association between LPAIV infection and daily local and regional movements. Among individuals, daily regional movements of LPAIV infected mallards in the last days of tracking were lower than those of non-infected birds. Moreover, these regional movements of LPAIV infected birds were additionally reduced by poor weather conditions (i.e. increased wind and/or precipitation and lower temperatures). Local movements of LPAIV infected birds in t

Umbrella review and Delphi study on modifiable factors for dementia risk reduction

A 2013 systematic review and Delphi consensus study identified 12 modifiable risk and protective factors for dementia, which were subsequently merged into the “LIfestyle for BRAin health” (LIBRA) score. We systematically evaluated whether LIBRA requires revision based on new evidence. To identify modifiable risk and protective factors suitable for dementia risk reduction, we combined an umbrella review of systematic reviews and meta-analyses with a two-round Delphi consensus study. The review of 608 unique primary studies and opinions of 18 experts prioritized six modifiable factors: hearing impairment, social contact, sleep, life course inequalities, atrial fibrillation, and psychological stress. Based on expert ranking, hearing impairment, social contact, and sleep were considered the most suitable candidates for inclusion in updated dementia risk scores. As such, the current study shows that dementia risk scores need systematic updates based on emerging evidence. Future studies will validate the updated LIBRA score in different cohorts. Highlights: An umbrella review was combined with opinions of 18 dementia experts. Various candidate targets for dementia risk reduction were identified. Experts prioritized hearing impairment, social contact, and sleep. Re-assessment of dementia risk scores is encouraged. Future work should evaluate the predictive validity of updated risk scores

Environmental morphing enables informed dispersal of the dandelion diaspore

Animal migration is highly sensitised to environmental cues, but plant dispersal is considered largely passive. The common dandelion, Taraxacum officinale, bears an intricate haired pappus facilitating flight. The pappus enables the formation of a separated vortex ring during flight; however, the pappus structure is not static but reversibly changes shape by closing in response to moisture. We hypothesised that this leads to changed dispersal properties in response to environmental conditions. Using wind tunnel experiments for flow visualisation, particle image velocimetry, and flight tests we characterised the fluid mechanics effects of the pappus morphing. We also modelled dispersal to understand the impact of pappus morphing on diaspore distribution. Pappus morphing dramatically alters the fluid mechanics of diaspore flight. We found that when the pappus closes in moist conditions, the drag coefficient decreases and thus the falling velocity is greatly increased. Detachment of diaspores from the parent plant also substantially decreases. The change in detachment when the pappus closes increases dispersal distances by reducing diaspore release when wind speeds are low. We propose that moisture-dependent pappus-morphing is a form of informed dispersal allowing rapid responses to changing conditions

Modelos propulsivos: novas teorias velhas polémicas

A propulsão no meio aquático é baseada na interacção entre o movimento do nadador e o meio envolvente. Neste âmbito, o objectivo principal dos movimentos propulsivos é o de transmitir momento linear ao meio. Esta transferência de momento entre o corpo do nadador e o meio aquático é mediada pela 3ª Lei de Newton (Lei da acção reacção). A forma mais fácil e económica de gerar propulsão seria pela utilização de pontos de apoio rígidos, nos quais a mão se pudesse fixar, permitindo o deslocamento do corpo do nadador para a frente, tal como sucede no MAD System (Measuring Active Drag System; Hollander et al., 1986)