Improving maximum walking distance in early peripheral arterial disease: Randomised controlled trial

The purpose of this study was to determine the impact of increased physical activity and cessation of smoking on the natural history of early peripheral arterial disease, We conducted a randomised controlled trial in Perth, Western Australia, involving 882 men with early peripheral arterial disease identified via population-based screening using the Edinburgh Claudication Questionnaire and the ankle:brachial index. Members of the control group (n = 441) received usual care from their general practitioner while members of the intervention group (n = 441) were allocated to a stop smoking and keep walking regime - a combined community-based intervention of cessation of smoking (where applicable) and increased physical activity. Postal follow-up occurred at two and 12 months post-entry into the trial. The main outcome of interest was maximum walking distance. There were no statistically significant differences in the characteristics of the intervention and usual care groups at recruitment. Follow-up information at two and 12 months was available for 85% and 84% of participants, respectively. At 12 months, more men allocated to the intervention group had improved their maximum walking distance (23% vs 15%; chi(2) = 9.74, df = 2, p = 0.008). In addition, more men in the intervention group reported walking more than three times per week for recreation (34% vs 25%, p = 0.01). Although not statistically significant, more men in the intervention group who were smokers when enrolled in the trial had stopped smoking (12% vs 8%, p = 0.43). It is concluded that referral of older patients with intermittent claudication to established physiotherapy programs in the community can increase levels of physical activity and reduce disability related to peripheral arterial disease. A combination of simple and safe interventions that are readily available in the community through physiotherapists and general practitioners has the potential to improve early peripheral arterial disease.

Heuristics for minimizing the maximum within-clusters distance

The clustering problem consists in finding patterns in a data set in order to divide it into clusters with high within-cluster similarity. This paper presents the study of a problem, here called MMD problem, which aims at finding a clustering with a predefined number of clusters that minimizes the largest within-cluster distance (diameter) among all clusters. There are two main objectives in this paper: to propose heuristics for the MMD and to evaluate the suitability of the best proposed heuristic results according to the real classification of some data sets. Regarding the first objective, the results obtained in the experiments indicate a good performance of the best proposed heuristic that outperformed the Complete Linkage algorithm (the most used method from the literature for this problem). Nevertheless, regarding the suitability of the results according to the real classification of the data sets, the proposed heuristic achieved better quality results than C-Means algorithm, but worse than Complete Linkage.

Palynology on sediment profile Tso Kar in Ladakh

Palynological investigation of a 410 cm long core section from Tso Kar (33°10'N, 78°E, 4527 m a.s.l.), an alpine lake situated in the arid Ladakh area of NW India at the limit of the present-day Indian summer monsoon, was performed in order to reconstruct post-glacial regional vegetation and climate dynamics. The area was covered with alpine desert vegetation from ca. 15.2 to 14 kyr BP (1 kyr=1000 cal. years), reflecting dry and cold conditions. High influx values of long-distance transported Pinus sylvestris type pollen suggest prevailing air flow from the west and northwest. The spread of alpine meadow communities and local aquatic vegetation is a weak sign of climate amelioration after ca. 14 kyr BP. Pollen data (e.g. influx values of Pinus roxburghii type and Quercus) suggest that this was due to a strengthening of the summer monsoon and the reduced activity of westerly winds. The further spread of Artemisia and species-rich meadows occurred in response to improved moisture conditions between ca. 12.9 and 12.5 kyr BP. The subsequent change towards drier desert-steppe vegetation likely indicates more frequent westerly disturbances and associated snowfalls, which favoured the persistence of alpine meadows on edaphically moist sites. The spread of Chenopodiaceae-dominated vegetation associated with an extremely weak monsoon occurred at ca. 12.2-11.8 kyr BP during the Younger Dryas interstadial. A major increase in humidity is inferred from the development of Artemisia-dominated steppe and wet alpine meadows with Gentianaceae after the late glacial/early Holocene transition in response to the strengthening of the summer monsoon. Monsoonal influence reached maximum activity in the Tso Kar region between ca. 10.9 and 9.2 kyr BP. The subsequent development of the alpine meadow, steppe and desert-steppe vegetation points to a moderate reduction in the moisture supply, which can be linked to the weaker summer monsoon and the accompanying enhancement of the winter westerly flow from ca. 9.2 to 4.8 kyr BP. The highest water levels of Tso Kar around 8 kyr BP probably reflect combined effect of both monsoonal and westerly influence in the region. An abrupt shift towards aridity in the Tso Kar region occurred after ca. 4.8 kyr BP, as evidenced by an expansion of Chenopodiaceae-dominated desert-steppe. Low pollen influx values registered ca. 2.8-1.3 kyr BP suggest scarce vegetation cover and unfavourable growing conditions likely associated with a further weakening of the Indian Monsoon.

Abb. 3 Change of altitude in the EGIG-West-East-profile

The members of the two International Glaciological Greenland Expeditions (EGIG) in 1959 and 1968 determined the altitudes in the West-East-profile by levelling. The comparison of these two measurements gives evidence of the change of altitudes and of the surface-waves. The ways of measurement and of analysis are described here. The graphic representation of the result is discussed here in connexion with the possible causes.