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The prokaryotic abundance and diversity in three cold, oligotrophic Patagonian lakes (Témpanos, Las Torres and Mercedes) in the northern region Aysén (Chile) were compared in winter and summer using 16S rRNA fluorescence in situ hybridization and PCR-denaturing gradient gel electrophoresis technique. Prokaryotic abundances, numerically dominated by Bacteria, were quite similar in the three lakes, but higher in sediments than in waters, and they were also higher in summer than in winter. The relative contribution of Archaea was greater in waters than in sediments, and in winter rather than in summer. Despite the phylogenetic analysis indicated that most sequences were affiliated to a few taxonomic groups, mainly referred to Proteobacteria (consisting of Beta-, Alpha- and Gammaproteobacteria) and Euryarchaeota (mainly related to uncultured methanogens), their relative abundances differed in each sample, resulting in different bacterial and archaeal assemblages. In winter, the abundance of the dominant bacterial phylotypes were mainly regulated by the increasing levels of total organic carbon in waters. Archaeal abundance and richness appeared mostly influenced by pH in winter and total nitrogen content in summer. The prokaryotic community composition at Témpanos lake, located most northerly and closer to a glacier, greatly differed in respect to the other two lakes. In this lake was detected the highest bacterial diversity, being Betaproteobacteria the most abundant group, whereas Alphaproteobacteria were distinctive of Mercedes. Archaeal community associated with sediments was mainly represent by members related to the order of Methanosarcinales at Mercedes and Las Torres lakes, and by Crenarchaeota at Témpanos lake. Our results indicate that the proximity to the glacier and the seasonality shape the composition of the prokaryotic communities in these remote lakes. These results may be used as baseline information to follow the microbial community responses to potential global changes and to anthropogenic impacts.

Reports of epidemiological surveys do not always provide adequate careful descriptions of the methodology used and the sociocultural context involved. Galicia, a natural region in south-west Europe, possesses certain characteristics that differ from those in other communities within the Spanish state. Galician is a Romance language, which is, in fact, closer to Portuguese than it is to Spanish. The population (2.7 million inhabitants) is widely dispersed, with two-thirds of them living in the countryside. More than 18% are older than 65, and the educational level of this elderly population is low. A total of 681 persons over 60 years of age were interviewed in their homes using the DIS-III as the main diagnostic instrument during the second phase of the Galicia Study of Mental Health of the Elderly. This paper analyses some methodological implications of this epidemiological study, focusing on the translation of the DIS into Galician and its performance and acceptability in thiscommunity. The possible cultural bias that can affect the rates of prevalence in some specific disorders, the limitations of lifetime prevalence and the advantages of using six-month prevalence rates is discussed. Besides some interesting anecdotes, which are described in the article, the main result is the very high acceptance of DIS-III in this elderly population.

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In Chile, the Eucalyptus nitens (H. Deane & Maiden) Maiden × E. globulus Labill. hybrid presents the highest production potential due to its desirable characteristics for the production of cellulose. Nevertheless, its low ability to rooting complicates the clonal propagation in nurseries, with the need for new alternatives to increase rooting. The objective of this research was to evaluate the effect of rhizobacteria in the adventitious rooting of mini-cuttings of two hybrid E. nitens × E. globulus clones, wherein 106 rhizospheric bacterial isolates from five species and hybrids of Eucalyptus spp. were used. The mini-cuttings were treated at the base with a 20 mL liquid suspension of rhizobacterial strains. In addition, cultured bacteria were applied by manual sprinklers in the rooting substrate. In the first trial, 38% of rhizobacteria increased significantly rooting of X-64 clone mini-cuttings. Of these, in a second trial, 50% of rhizobacteria maintained their effect in promoting the rooting in two clones, and in the third trial among the 20 strains evaluated, 10 strains increased rooting in both clones. The rhizobacteria that had the most consistent effect in the rooting increase of the mini-cuttings were species of Bacillus and Pseudomonas sp., as well as the genera Chryseobacterium, Mucilaginibacter and Rhodococcus sp., with these results, it is concluded that 10 rhizobacterial isolates have increased the adventitious rooting of minicuttings of two hybrid clones of E. nitens × E. globulus, and these inoculants could be used in periods of underperformance of minicuttings, in order to optimize their performance.