No abstract

Microwave irradiation was used for the fixation of eggs, nymphs, and adult Boophilus spp. ticks. Although optimal temperatures for fixation of the different tick stages varied, heating to 58 degrees C of adult ticks submerged in either PBS or fixative was found to be sufficient. After microwave fixation, whole adult ticks, hand held, were sectioned with a sharp razor blade. The resulting sections revealed the in situ histoanatomy of the tick. Thin sections of ticks were obtained after either paraffin or polyester wax embedding. Microwave fixation combined with polyester wax embedding made serial thin sections of the different stages of Boophilus ticks possible. The technique preserved antigens as demonstrated by the immunostaining of lymphocytes and erythrocytes infected with Babesia microti in mouse tissues subjected to the same treatment as the ticks. With the microwave fixation-polyester wax technique, the specimen preparation time from fixation to the section on the glass slide was reduced to less than 8 h.

No abstract

Freshwater scarcity is a significant concern due to climate change in some regions of Brazil; likewise, evaporation rates have increased over the years. Floating photovoltaic systems can reduce water evaporation from reservoirs by suppressing the evaporating area on the water surface. This work evaluated the effects of floating photovoltaic systems on water evaporation rates in the Passaúna Reservoir, southeastern Brazil. Meteorological data such as temperature, humidity, wind speed, and solar radiation were used to estimate the rate of water evaporation using FAO Penman–Monteith, Linacre, Hargreaves–Samani, Rohwer, and Valiantzas methods. The methods were tested with the Kruskal–Wallis test, including measured evaporation from the nearest meteorological station to determine whether there were significant differences between the medians of the methods considering a 95% confidence level for hypothesis testing. All methods differed from the standard method recommended by the FAO Penman–Monteith. Simulations with more extensive coverage areas of the floating photovoltaic system were carried out to verify the relationship between the surface water coverage area and the evaporation reduction efficiency provided by the system and to obtain the avoided water evaporation volume. For the floating photovoltaic system with a coverage area of 1265.14 m2, an efficiency of 60.20% was obtained in reducing water evaporation; future expansions of the FPS were simulated with coverage areas corresponding to energy production capacities of 1 MWp, 2.5 MWp, and 5 MWp. The results indicated that for a floating photovoltaic system coverage area corresponding to 5 MWp of energy production capacity, the saved water volume would be enough to supply over 196 people for a year. More significant areas, such as covering up the entire available surface area of the Passaúna reservoir with a floating photovoltaic system, could save up to 2.69 hm3 of water volume annually, representing a more significant value for the public management of water resources.

RESUMO Com a escassez da disponibilidade de água doce e o aumento da demanda de água no mundo e no Brasil, uma das alternativas são os sistemas de dessalinização de água, que removem os sais das águas salobra ou salgada. Este estudo teve como objetivo avaliar a eficiência de um sistema piloto de dessalinização de água salobra a qual foi obtida a partir da mistura de águas do mar e de rio até atingir concentração de sólidos dissolvidos totais (SDT) de 1.500 mg.L-1. O sistema piloto de dessalinização, com capacidade de 1,0 m3.h-1, é composto de ultrafiltração (UF) e abrandamento como pré-tratamento à osmose reversa (OR). Foram realizadas análises de qualidade da água na entrada e saída das unidades de tratamento relativas a SDT, condutividade elétrica, turbidez, pH, cor aparente, alcalinidade, dureza total, cálcio, magnésio, cloreto, sulfato e temperatura. Foram avaliadas a pressão osmótica, o fluxo de filtração e a taxa de recuperação de água no sistema de OR. Com os resultados obtidos, conclui-se que a eficiência de remoção de SDT e condutividade foi de 99%. A UF foi eficiente na remoção de turbidez, enquanto a OR apresentou maiores eficiências de remoção de sais. O sistema piloto de tratamento foi capaz de remover todos os parâmetros estudados. A taxa de recuperação na OR foi de 74,64%.