Whole breast and regional nodal irradiation in prone versus supine position in left sided breast cancer

Background: Prone whole breast irradiation (WBI) leads to reduced heart and lung doses in breast cancer patients receiving adjuvant radiotherapy. In this feasibility trial, we investigated the prone position for whole breast + lymph node irradiation (WB + LNI). Methods: A new support device was developed for optimal target coverage, on which patients are positioned in a position resembling a phase from the crawl swimming technique (prone crawl position). Five left sided breast cancer patients were included and simulated in supine and prone position. For each patient, a treatment plan was made in prone and supine position for WB + LNI to the whole axilla and the unoperated part of the axilla. Patients served as their own controls for comparing dosimetry of target volumes and organs at risk (OAR) in prone versus in supine position. Results: Target volume coverage differed only slightly between prone and supine position. Doses were significantly reduced (P < 0.05) in prone position for ipsilateral lung (Dmean, D2, V5, V10, V20, V30), contralateral lung (Dmean, D2), contralateral breast (Dmean, D2 and for total axillary WB + LNI also V5), thyroid (Dmean, D2, V5, V10, V20, V30), oesophagus (Dmean and for partial axillary WB + LNI also D2 and V5), skin (D2 and for partial axillary WB + LNI V105 and V107). There were no significant differences for heart and humeral head doses. Conclusions: Prone crawl position in WB + LNI allows for good breast and nodal target coverage with better sparing of ipsilateral lung, thyroid, contralateral breast, contralateral lung and oesophagus when compared to supine position. There is no difference in heart and humeral head doses

The Eemian - local sequences, global perspectives: introduction

Wetensch. publicatieFaculty of Archeolog

The establishment of red oak and pedunculate oak seedlings in the experimental forest of Aelmoeseneie at Gontrode (Belgium)

The  natural regeneration of American oak and pedunculate oak under cover occurs  regularly in the Aelmoeseneie forest. Nevertheless, these seedlings tend to  establish very difficultly. They often die off after one year. In order to  survive, the crown cover has to be strongly opened after the first year.      One year old seedlings of American oak, however, grow slightly better under  cover than under partial freestand. The seedlings of pedunculate oak, on the  other hand, hardly react on the different light conditions.     The American oak seeds are of good quality. A considerable amount is eaten  by the birds. The seeds of pedunculate oak are of a minor quality; an  important number is eaten by the worms. The growth of the seedlings in the  Aelmoeseneie forest does not always correspond to the growth on other sites.</jats:p

Nonnegativity Preserving Macro-Element Interpolation of Scattered Data

Abstract. Nonnegative bivariate interpolants to scattered data are constructed using some C 1 macro-element spline spaces. The methods are local, and rely on adjusting gradients at the data points to insure nonnegativity of the spline when the original data is nonnegative. More general range-restricted interpolation is also considered