Possibilidades e limitações no uso da temperatura em cromatografia líquida de fase reversa

High-temperature liquid chromatography (HTLC) is a technique that presents a series of advantages in liquid phase separations, such as: reduced analysis time, reduced pressure drop, reduced asymmetry factors, modified retentions, controlled selectivities, better efficiencies and improved detectivities, as well as permitting green chromatography. The practical limitations that relate to instrumentation and to stationary phase instability are being resolved and this technique is now ready to be applied for routine determinations.

Avaliação de índices de firmeza para abacaxi minimamente processado em fatias tratadas com soluções de sais de cálcio

Fresh-cut sliced fruits and vegetables are ready to eat immediately and their sensorial characteristics should be similar to fresh product. Although most of the studies in this area are focused on vegetables, there is a great market potential for fresh-cut sliced fruits, mainly for those which exhibit some commercialization or preparation difficulties such as pineapple. The objective of this work was to evaluate the effect of 1% and 3% concentrations of calcium salts (chloride, sulphate and lactate) on pH, total soluble solids and firmness values of minimally processed pineapple slices. Two types of indenters and three firmness indexes were investigated aiming to identify the best index. Results showed that calcium sulphate 3% kept average firmness index up to 44.45% higher than the index value of the control. Even though both indenters exhibited similar variability the cylindrical one was able to point out more differences between control and treatments than the cylindrical borer indenter.

Success attitudes of young ophthalmologists in the first decade of their career

PURPOSE: To describe the main success attitudes of young ophthalmologists in the first decade of their career. METHODS: This descriptive study comprised subjects selected from a sample of ophthalmologists who were participating in a congress, using a semi-structured questionnaire. The inclusion criteria were as follows: ophthalmologists under the age of 40 years, within 5-10 years from ophthalmology residency conclusion. The subjects were asked about the three main success attitudes in their personal experience during the first years of ophthalmology practice. After the initial results, the 10 most frequently mentioned attitudes were listed and volunteers were again interviewed to choose, within the latter list, the three main attitudes. RESULTS: Forty-eight ophthalmologists were interviewed, 24 (50%) were male; the mean age was 37 years (SD: 2 years, range: 33-40 years) and the mean time from ophthalmology residency conclusion was 8 years (SD: 1 year, range: 5-10 years). The frequency of such mentioned success attitudes were as follows: to invest in professional updating (22.9%), to have a good relationship with patients and professional partners (18.8%), to prioritize individual and family happiness (12.5%), initially to work in an established group (11.1%), to work in public service (9.7%), to have their own business with a homogeneous group (7.6%), to save money (7.6%), to be ready to resume work (4.2%), to get business administration skills (4.2%), and to have professional insurance (0.7%). CONCLUSIONS: The three main success attitudes consisted in investing in professional updating (22.9%), maintaining a good relationship with patients and professional partners (18.8%), and prioritizing individual and family happiness (12.5%). Although these results should not be generalized, they are helpful not only for those ophthalmologists at the beginning of a career but also those who want to reflect on what to prioritize in their professional practice.