[en] Based on the conducted experiment for lignite from 'Maritsa Iztok' fluidized bed combustion, an analysis is done of the impact of different fuel parameters (diameter of coal particles; bed temperature; ash content of the coal particles, oxygen content of the fluidized agent ) on NOx emissions

[en] Background. The aim of the retrospective study was to determine whether 6 classical prognostic factors might predict a disease-free survival (DSF) in stage I breast carcinoma. Patients and methods. We analysed 181 patients who were operated on from 1991 through 1995. Measurements were made to find the association between the incidence of recurrence and prognostic features (size; histological subtype; lymphatic/vascular invasion (LVI); histological grade; hormone receptor status; age). Results. There were 4 cases with locoregional recurrences (2.2%), 6 with locoregional and distant metastases (3.3 %) and 13 women with distant metastases (7.2 %). In univariate analysis, the following prognostic factors were significantly related to DSF: tumour size, age and LVI. In the multivariate analysis age (p = 0.007) and LVI (p 0.00001) remained firmly associated with DSF, although the tumour size (p 0.067) lost its significance. Conclusions. Our experience indicates that the combined use of the tumour size, LVI and age may be a better predictor of recurrence in T1N0M0 breast cancer. (author)