Biological-effective versus conventional dose volume histograms correlated with late genitourinary and gastrointestinal toxicity after external beam radiotherapy for prostate cancer: a matched pair analysis

BACKGROUND: To determine whether the dose-volume histograms (DVH's) for the rectum and bladder constructed using biological-effective dose (BED-DVH's) better correlate with late gastrointestinal (GI) and genitourinary (GU) toxicity after treatment with external beam radiotherapy for prostate cancer than conventional DVH's (C-DVH's). METHODS: The charts of 190 patients treated with external beam radiotherapy with a minimum follow-up of 2 years were reviewed. Six patients (3.2%) were found to have RTOG grade 3 GI toxicity, and similarly 6 patients (3.2%) were found to have RTOG grade 3 GU toxicity. Average late C-DVH's and BED-DVH's of the bladder and rectum were computed for these patients as well as for matched-pair control patients. For each matched pair the following measures of normalized difference in the DVH's were computed: (a) δ(AUC )= (Area Under Curve [AUC] in grade 3 patient – AUC in grade 0 patient)/(AUC in grade 0 patient) and (b) δ(V60 )= (Percent volume receiving = 60 Gy [V60] in grade 3 patient – V60 in grade 0 patient)/(V60 in grade 0 patient). RESULTS: As expected, the grade 3 curve is to the right of and above the grade 0 curve for all four sets of average DVH's – suggesting that both the C-DVH and the BED-DVH can be used for predicting late toxicity. δ(AUC )was higher for the BED-DVH's than for the C-DVH's – 0.27 vs 0.23 (p = 0.036) for the rectum and 0.24 vs 0.20 (p = 0.065) for the bladder. δ(V60 )was also higher for the BED-DVH's than for the C-DVH's – 2.73 vs 1.49 for the rectum (p = 0.021) and 1.64 vs 0.71 (p = 0.021) for the bladder. CONCLUSIONS: When considering well-established dosimetric endpoints used in evaluating treatment plans, BED-DVH's for the rectum and bladder correlate better with late toxicity than C-DVH's and should be considered when attempting to minimize late GI and GU toxicity after external beam radiotherapy for prostate cancer

Principles and requirements for the soil texture analysis according to methods recommended by International Standard Organization [ISO]

For several years now the Polish Normalisation Committee (PKN) has been angaged in the process of introduction (and implementation) of international standards complying with the Internationsl Standard Organsation (ISO) into the set of of Polish Standards.At present, in the PKN Commission of Soil Physics, a number of such standards are being prepared (translated) -including a very comprehensive standard dealing with partiele size distribution determination in soil material-ISO 11277 [6], Some principles and requirements included in this standard differ significantly from those commonly accepted and widely in use now in numerous pedologie laboratories in Poland [7,8]. Below there are some of the most important differences: (1 ) the requirement to remove organic matter from test samples (using 30% v/v solution of H2O2), (2) the requirement to remove water soluble salts and gypsum (to electrical conductivity 0,4 dS/m), (3) sample dispersion process must be longer than 18 hours. Many other requirements, of relatively lesser importance, in many cases also do not correlate with those commonly accepted in our laboratories

Comparison of soil texture classification according to the new Polish Standard, PTG and international classifications [FAO and USDA]

The classification into soil fractions found in the new Polish Standard PN-R-04033 is fully comparable- with the international classifications (FAO/USDA) in question. The following diameters were adopted as the main groups of soil fractions: stones >75 mm, gravel 75-2 mm, sand 2.0-0.05 mm, silt 0.05-0.002 mm and clay <0.002 mm. On the other hand, soil fractions classification according to the Polish Soil Science Society (PTG), including so-called fine particles (<0.02 mm), is not compatible with both the new Polish Standard and the discussed international classifications. This also refers lo the classification into textural groups according to PTG. However, the classification into textural groups according lo Polish Standard is quite similar to international classifications

Zasoby prochnicy w glebach Lednickiego Parku Krajobrazowego

W pracy określono zasoby próchnicy w glebach Lednickiego Parku Krajobrazowego, obejmującego obszar o zróżnicowanej geomorfologii i długotrwałej, wyraźnej antropopresji. Badaniami objęto 60 profili mineralnych gleb uprawnych. Generalnie najwyższymi zasobami próchnicy odznaczają się czarne ziemie, a następnie gleby płowe. Najmniej materii organicznej stwierdzono z reguły w arenosolach. W pracy wykazano też, iż intensywna i długotrwała działalność człowieka może doprowadzić do stanu, że wyższe zasoby próchnicy posiadają gleby usytuowane na piaszczystych pagórkach (np. niektóre arenosole), aniżeli gleby wytworzone na gliniastej morenie dennej.The paper deals with resources of organic matter in soils of Lednicki Landscape Park, compraising area of differentiated geomorphology and intensive anthropogenic activities. More than 45 mineral arable soil profiles have been investigated. Generally, highest amounts [Mg/ha] of humus contain Black Earths, medium - Lessives Soils and the lowest amount were found in the Arenosols (sandy soils). The investigations have shown also, that long-term intensive man-activities can cause that organic matter in sandy hilly area is greater than in soils formed from loamy ground moraine

Mobilization of aluminium under acid precipitation (a laboratory experiment) in the typical soils of the Wielkopolski National Park

A laboratory simulation of acid rain was performed in which soil monoliths from the Wielkopolski National Park area were sprinkled with water solutions of sulphuric acid of pH 3.0 or 2.0, and for reference with distilled water of pH 5.6. The form and amount of the washed out aluminium as well as changes in the chemical properties of the soil studied were determined. The process of aluminium release proved particularly dangerous for acidic or slightly acidic soils which cover a large part of the National Park area

Effect of soil inundation on its properties in the Region of Swiecko during summer flooding

The present experiments were earned out pn the soilrf of the Rybocice polder near Swiecko, which was purposefully flooded with waters of the Odra river during the summer flood of' 1977 that causet complete destruction of crops and meadow sward. The flooded areas remained under water for more than 30 days. The dominant soils found in this area are river alluvial soils (Fluvi- sols) of varying texture. Rceause of their location and poorly operating drainage system, the discussed soils are periodically too wet by nature or water-logged. In the spring (March/April) of 1998 the ground water table occurred at the depth of 30 cm on damaged grasslands and at 90 cm on some arable Holds. The content of organic carbon ranged from 0.7 to 3.2% in horizon A with depth of approximately 30 cm. Soil reaction was found to vary considerably - from pH (KCI) 4.2 to pH 7.6. Long purposeful inundation with flood waters was not found to have caused significant negative effects on chemical properties of the examined soils. No noticeable contamination with heavy metals (Pb„ Cu, Zn, Cd, Cr and Mn) or polieyclic aromatic hydrocarbons (PAH) was observed. Bulk density in this region, without any treatment from the period of flooding to the spring of 1998 was approximately 1.60 Mg/m3 as compared with 1.40 Mg/m3 on the field cultivated (ploughed) in spring and sown with spring cereal. The mean crop yield in 1998, when appropriate agro-techniques were applied, did not vary significantly from the long-term averages

Flotation after a direct contact of flotation reagents with carbonate particles. Part 1, Model investigations

Carbonate fluorapatite (francolite), calcite and dolomite separately, as well as their model mixtures, were subjected to flotation after conditioning the particles with microemulsion consisting of 20% of Custafloat AR27 (collector, blend of fatty acid soaps and sulfates), 55% fuel oil #5 and 25% water at 70% solids density and subsequent pulp dilution with water to 25% solids. The best separation of carbonate fluorapatite from calcite and dolomite occurred at pH 8.5 and microemulsion dose between 0.9 and 1.5 kg/Mg, 1.5 min conditioning time and 2 minutes of flotation time. The obtained flotation concentrates using 1.5 kg/Mg of collector contained 84% carbonate fluorapatite (34% P2O5) with 84% recovery. The 84/84 separation efficiency in terms of grade-recovery indices points to promising results which can be obtained for real phosphate ores