RESUMO A deriva da pulverização de inseticidas pode proporcionar a redução da eficiência de controle e perda para o ambiente. Desta forma, foi conduzido um estudo com o objetivo de estudar o efeito de diferentes pontas de pulverização e adição de adjuvantes na calda inseticida, em relação ao espectro de gotas e deriva em túnel de vento. Os experimentos foram conduzidos no delineamento inteiramente casualizado, com quatro repetições, no esquema fatorial 5 × 3, constituído por cinco caldas, uma apenas com água e outras quatro com inseticida tiametoxam + lambda-cialotrina (sem adjuvante, Oro-solve, Wetcit Gold e Orobor N1), combinadas com três pontas de pulverização (AXI, JFC e J3D). Foi avaliado o espectro das gotas, através do diâmetro mediano volumétrico, amplitude relativa e porcentagem do volume de gotas com diâmetro ≤ 100 µm. A deriva foi avaliada em túnel de vento, a diferentes distâncias: 5, 10 e 15 m. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey. Além disso, foram realizadas análises de componentes principais. A aplicação do inseticida com os adjuvantes combinados com as diferentes pontas de pulverização alterou o espectro de gotas e o risco da deriva. A ponta AXI e a J3D associada aos adjuvantes Oro-solve e Wetcit Gold apresentaram maiores diâmetros medianos volumétricos das gotas e deriva a 5 m.

ABSTRACT Insecticide spray drift can lead to reduced control efficiency and loss of product to the environment. Thus, we conducted a study to evaluate the effect of different spray nozzles and the addition of adjuvants in insecticide spray on the resulting droplet spectrum and wind tunnel drift. All experiments were conducted in a completely randomized design with four repetitions using a 5 × 3 factorial scheme. Five spraying solutions were studied; one contained only water and the other four comprised thiamethoxam + lambda-cyhalothrin (no adjuvant, Oro-solve, Wetcit Gold, and Orobor N1), in combination with three spray nozzles (AXI, JFC, and J3D). The droplet spectrum was evaluated through the volumetric median diameter, relative amplitude, and percentage of the droplet volume with diameter ≤ 100 µm. The drifts were evaluated in a wind tunnel at 5, 10, and 15 m. Data were subjected to analysis of variance and means were compared using the Tukey’s test. In addition, a principal component analysis was performed. Application of the insecticide with the adjuvants combined with the different nozzles changed the droplet spectrum and the risk of drift. The AXI nozzle and the J3D associated with the Oro-solve and Wetcit Gold adjuvants resulted in a greater volumetric median diameter of the droplets and drifts were observed at 5 m.

Biodiesel made from oils is rich in polyunsaturated fatty acids methyl esters, and, consequently, presents high tendency to oxidize. Biodiesel made from fats, on the other hand, is mainly comprised by saturated chains. Although it is highly stable, they easily crystalize at low temperatures. Blends from both can exhibit optimized properties. In this work, oxidative stability, expressed by induction period (IP), and cold filter plugging point (CFPP) of blends from palm, palm kernel, babassu, tallow or lard biodiesels with soy one were measured. Biodiesel samples were prepared by two steps transesterification methodology with KOH catalysis followed by H2SO4. IP increases, as the fat biodiesel content in the blend is higher, as expected. Blends comprised by 60% of fat biodiesel by volume had their IP increased from 1.5 (lard) to 2 times (palm kernel), compared to soy one. At this level, IP was found 8 h or higher, except for palm, which 80% was required. CFPP was observed at 8 °C or lower for the blends containing up to 60% of all the fat biodiesel, except for the palm one, which a 20% content must not be surpassed. Palm kernel 80% biodiesel blend reached the Brazilian specification, that is, IP higher than 12 h and CFPP lower than 5 °C.

Cento e vinte e cinco ratos Wistar foram infectados pelo T. cruzi, cepa Colômbia, 2000 parasitas/kg peso corporal, via intraperitoneal, logo após o desmame. Cinqüenta e oito animais sobreviveram à fase aguda da infecção e foram utilizados no presente experimento. Vinte e oito animais semelhantes mas não infectados serviram como controles. O eletrocardiograma basal de cada animal foi registrado quando o rato estava com 6 meses de idade. Para tanto, utilizamos 3 derivações precordials bem como as derivações clássicas a fim de obtermos o mais completo ECG basal possível. Alterações eletrocardiográficas semelhantes às encontradas na Cardiopatia Chagásica Crônica humana, que não tinham sido descritas previamente neste modelo, foram observadas em 44% dos ratos infectados pelo T. cruzi: Desvio do SÂQRS à esquerda (22%). desvio do SÂQRS à direita (7%), complexo QRS bizarro e/ou alargado (14%), supradesni-velamento do ponto J (3%). Com base nestes resultados, acreditamos que o ECG basal constitui importante metodologia para o estudo da, Cardiopatia Chagásica Crônica experimental do rato.

A total of 125 rats were infected with the Colômbia strain of T. cruzi (2000 parasites/g) shortly after weaning. Of these, 58 survived the acute phase and were used in the present experiment. Twenty eight similar but not infected rats served as controls. All rats were submitted to the resting ECG When they were 6 months old. Classic and 3 precordial leads were employed in order to record the ECG as completely as possible. Electrocardiographic changes similar to those found in human chronic Chagas' heart disease and not previously described in this model were found in 44% of the T. cruzi-infected rats: left axis deviation (22%), right axis deviation (7%), lengthened and bizarre QRS complex (14%) and abnormal J point elevation (3%). On the basis of these results, we believe that the resting ECG constitutes a valuable tool for studying experimental chronic Chagas' heart disease in rats.