Métodos de extração de fósforo e micronutrientes em latossolos com uso de energia ultrassônica

Assessing the soil nutrient availability to plants under lab conditions is one of the main challenges to Soil Fertility and Chemistry, due to the complex behavior and the interaction of the soil properties. Many extractant solutions associated with mechanical forms of agitation have been proposed, showing different correlations with plant growth and nutrients absorption. Using ultrasonic energy is a agitation procedure of the soil:extractant solution suspension (based on the cavitation phenomenon). It allows the establishment of relations between the amount of extracted nutrient and the ultrasonic energy level. Thus, this work aims: to evaluate the effect of cavitation intensity on the extraction of P, Zn, Cu, Mn and Fe in soil samples from five Latosols under different uses around Uberlândia and Uberaba, Minas Gerais State; to obtain extracting curves as function of ultrasonic energy levels; and to obtain an index from extracting curves to expresses the nutrient retention by the soil solid phase. A soil-solution suspension (ratio 1:10) was sonicated using a probe ultrasound equipment under different combinations of power and time: i) 30 W for 35, 70, 140 and 280 s; ii) 50 W for 21, 42, 84 and 168 s; and iii) 70 W for 15, 30, 60 and 120 s. The extractant solutions used were Mehlich-1 (for all elements), Olsen and distilled water for P. After each sonication, P concentration was quantified by molybdenum blue colorimetric method and Zn, Cu, Mn and Fe by flame atomic absorption spectrophotometry. The cavitation intensity did not affect the P extraction, only the total energy applied. The P extraction was influenced by extractant solution, decreasing as follows: Mehlich-1>Olsen>water. In cultivated Latosols, the P extraction increased linearly with ultrasonic energy, and the slope of the 1:1 linear regression reflects the P retention in the soil. The Zn and Fe extractions were influenced only by total energy applied. Mn and Cu extractions were influenced by both cavitation intensity and total ultrasonic energy. Soils containing similar amounts of P, Cu, Zn, Mn, and Fe may have a different extraction rate. Likewise, soils containing different amounts of those elements may have the same extraction rate.

Avaliação da eficácia da implementação de um pacote de medidas na prevenção de pneumonia associada à ventilação mecânica em unidade de terapia intensiva adulta

Background: Ventilator-associated pneumonia (VAP) is a health care related infection and the second leading cause of nosocomial infections linked to morbidity and mortality rates. Therefore, the implementation of care guideline protocols has become necessary for critically ill patients in ICUs in order to provide adequate treatment. Objective: To assess the impact of a package called FAST HUG in PAV ; analyze the risk factors for occurrence of VAP in adult patients at an ICU of a private hospital ; analyze the clinical characteristics of patients who were or were not submitted to the FAST HUG ; analyze the etiology of microorganisms related to EPI ; determine the cost of hospitalization in patients with pneumonia and in patients who received the FAST HUG.Methods: The study was performed in a private hospital that has an 8-bed ICU. It was divided into two phases: before implementing FAST HUG, from August 2011 to August 2012 and after the implementation of FAST HUG, from September 2012 to December 2013. An individual form for each patient in the study was filled out by using information taken electronically from the hospital medical records. The following data for each patient was obtained: age, gender, reason for hospitalization, the use of three or more types of antibiotics, length of stay, intubation time and progress. Findings: After the implementation of FAST HUG, there was an observable decrease in the occurrence of VAP (p <0.01), as well as a reduction in mortality rates (p <0.01). It also shows that the intervention performed in the study resulted in a significant reduction in ICU hospital costs (p <0.05).Conclusion: The implementation of FAST HUG reduced the cases of VAP. Thus, decreasing costs, reducing mortality rates and length of stay, which therefore resulted in an improvement to the overall quality of care.