Clear cutting exotic plantations favours natural regeneration processes in which seed banks may play an important role. In Andean high montane areas, after Pinus patula clear cutting, changes in soil pH and litter lead to increased fauna and flora biodiversity. However, the impactof these changes on seed banks remains unknown. The aims of the present study were to understand how seed bank richness, abundance, and composition changes after p. patula clear cutting, and to identify the role of above ground cover, pH and litter cover on these seed bank variations. The study was conducted in three areas with different post-clear cutting ages (0,2.5,4.5 years), a p. patula plantation and in a high Andean forest patch. All these sites were located between 3033 and 3100 m.a.s.l. Seed bank abundance, richness and the number of seeds of the ten most abundant species increased in areas with 2.5 and 4.5 years after clear cutting. Moreover, seed bank composition was different among study areas. These changes were related to increasing above ground vegetation cover and soil pH, and to decreasing litter cover. Seed banks contributed almost exclusively to the recovery of some herbaceous species; were corded only one tree species recruit from the seed banks (Baccharislatifolia) in the forest soils; therefore, the natural regeneration processes may be constrained. Our results high light the need to implement active restoration to accelerate high montane forest recovery in areas previously covered with pine tree plantations.

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SUMMARYThis literature review cross-contaminationevidence of periodontal pathogens, specificallyAggregatibacter actinomycetemcomitansbetween members of the same family,which includes spouses and children, aswell as to identify the more importanttransmission routes. Describing the possibleroutes of transmission of periodontalbacteria could lead to methods to preventor reduce microbial cross-contaminationbetween family members and possiblyreduce disease transmission.Key words: Periodontitis, microbiology,transmission, Aggregatibacter actinomycetemcomitans.

Electricity is one of the main inputs used in poultry production. An aviary needs electricity to feed the various motors and electrical devices that compose the lighting systems, exhaustion, heating, food, among others. Aiming to give incentives to producers of broiler chickens, specifically in the state of Paraná, Brazil, in 2007, the Night Poultry Program was implemented, in which the government grants discounts in electricity tariff for poultry farmers at night. In this work it was proposed two energy storage systems through the use of lead-acid batteries and batteries of nickel chloride and sodium to feed the of charge of four brazillian aviaries over one year of poultry housing. For this purpose, it was evalueted the use of a bank of batteries in higher tariff, period comprising the time of 9:30 pm to 6 am of the next day, and charging the battery bank in reduced tariff period. The experiment was conducted using the electricity meters installed in the aviaries, weekly data of each aviary were collected and the active energy values, obtaining the data for six lots corresponding to a year of poultry accommodation. From the total consumption of active energy, it was calculated the average daily electricity consumption (kWh) for the set of aviaries. This value was used as input for the sizing of the battery banks. The two proposed storage systems demonstrate an alternative to energy supply for the rural areas, however the economical analysys indicates inviability, since the initial investment of the banks of batteries is high compared with the costs avoided with electricity by using these systems.