Green manure in coffee systems in the region of Zona da Mata, Minas Gerais: characteristics and kinetics of carbon and nitrogen mineralization.

The use of green manure may contribute to reduce soil erosion and increase the soil organic matter content and N availability in coffee plantations in the Zona da Mata, State of Minas Gerais, in Southeastern Brazil. The potential of four legumes (A. pintoi, C. mucunoides, S. aterrimum and S. guianensis)to produce above-ground biomass, accumulate nutrients and mineralize N was studied in two coffee plantations of subsistence farmers under different climate conditions. The biomass production of C. mucunoides was influenced by the shade of the coffee plantation.C. mucunoides tended to mineralize more N than the other legumes due to the low polyphenol content and polyphenol/N ratio. In the first year, the crop establishment of A. pintoi in the area took longer than of the other legumes, resulting in lower biomass production and N2 fixation. In the long term, cellulose was the main factor controlling N mineralization. The biochemical characteristics, nutrient accumulation and biomass production of the legumes were greatly influenced by the altitude and position of the area relative to the sun

Antimicrobial evaluation of quinones and heterocyclic compounds against mycobacterium marinum, M. kansasii and M. abscessus

The resistance to antimicrobials and biocides observed in mycobacteria which do not cause tuberculosis (MNT) determines the necessity to develop drugs. The present study evaluated the activity of naphthoquinones and heterocyclic derivatives obtained from lapachol against Mycobacterium kansasii, M. marinum, and M. abscessus, through the REMA method. It was observed that lapachol was inactive against the three mycobateria species, while β-lapachone and nor-β-lapachone showed activity only against M. marinum. The most active substances for M. kansasii were the derivates 2, 3, 7, and 11, in which compound 2 (CMI = 0.96 μM) was the most active. For M. marinum, 2, 11, and 14 were the most active, while against M. abcessus the compound 3 was the only active. The results showed a wide and diversified resistance spectrum among the species studied, which could be related to the molecular structure and position of the substituting groups, indicating the potentiality of these molecules as antimicrobial prototypes.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Effect of partial soil wetting on transpiration, vegetative growth and root system of young orange trees

The wetted area fraction is a factor critical to the success of drip irrigation. This study aimed to evaluate the effect of partial soil wetting on transpiration, vegetative growth and root system of young orange trees. The experiment was carried out in a greenhouse where plants were grown in 0.5 m3boxes internally divided into compartments. The wetting of 12 % of soil area was tested on two types of soil cultivated with ‘Valencia’ orange trees grafted onto Rangpur lime and ‘Swingle’ citrumelo rootstocks. Transpiration was determined in 40 plants. Water extraction and root density were evaluated in the compartments. Transpiration is reduced by restriction in wetted soil area, and such reduction is influenced by the number of days after the beginning of partial irrigation, atmospheric evaporative demand and plant phenological stage. Mean transpiration of plants with partial irrigation was equivalent to 84 % of the mean transpiration of plants with 100 % of wetted soil area in the period studied. However, after 156 days of imposing partial irrigation there was no difference in transpiration between treatments. Plant acclimation was caused by an increase in root concentration in the irrigated area. After a period of acclimation, if the entire root system is wetted, soil water extraction becomes proportional to the percentage of wetted area after a short period of time. Despite the reduction in transpiration, there was no difference between treatments with 12 % and 100 % of wetted soil area in terms of vegetative growth

Análise da atividade e gasto fisiológico dos catadores de resíduos sólidos: a percepção da terapia ocupacional

The world’s transformation in the market has been causing changes in the working class. As those changes have come, the market calls for a high capacity from the workers. Due to that, the unemployment rate has increased and induced a new type of class worker: the Recyclable Material Collectors. In this job, the role of the collector is to return the materials to their commodity chain, and to accomplish this, two methods of collecting are used: one with a truck and the other with a manual collector car. This is one type of occupation which has an extenuating work time, where the worker is exposed to a high ergonomic risk. This study, which was labored from a quantitative and qualitative approach to exploratory method and field research, is intended to compare which collecting technique can be less weariness to the worker. To the purpose of comparison of the physiological work weight, the participants used the Polar FT7 frequency counter, which generated, in graphic form, the performance of the collector in both methods. According to the values presented, was concluded that three of the four participants had a higher physiological weariness by using the manual car collecting approach, concluding that this method is the one that brings most effort to the worker. Considering the results obtained in this research, it was possible to observe that the use of the manual car causes a higher damage to the health of the recyclable material collector.A transformação no mundo do trabalho tem causado mudanças no perfil da classe trabalhadora. Cada vez mais, o mercado de trabalho requer exigências e, como decorrência disso, a taxa de desemprego aumentou e fez surgir uma nova profissão, a de Catadores de Materiais Recicláveis. A função do catador é a de devolver os materiais à sua cadeia produtiva e, para isso, existem dois métodos de coleta: com o caminhão e com o carro manual de coleta. Essa é uma profissão que possui jornadas de trabalho extenuantes, nas quais o trabalhador está exposto a riscos ergonômicos. Esse estudo foi elaborado a partir de uma abordagem quantitativa e qualitativa de método explorátorio e pesquisa de campo; pretende comparar qual método de coleta causa menos desgaste ao trabalhador. Para fins de comparação da carga fisiológica do trabalho, os participantes utilizaram o frequencímetro Polar FT7 que gerou, em forma de gráfico, o desempenho do catador em ambos os métodos de coleta. De acordo com os valores expostos, avaliou-se que, dos 4 participantes, 3 apresentaram um maior desgaste fisiológico no método de coleta com o carro manual, sendo esta a forma pela qual o trabalhador realiza mais esforços. Considerando os resultados obtidos nessa pesquisa, foi possível observar que o uso do carro manual de coleta causa um maior prejuízo à saúde do catador de materiais recicláveis