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Background: High grade glioma (HGG) is the most common primary malignant brain tumor. Radiotherapy (RT) plays an important role in the treatment of this tumor. Aim: To compare the survival rates of HGG patients treated by conventional RT and those treated by hypofractionated or hyperfractionated RT combined with chemotherapy in two centers in Upper Egypt. Methods: Data of HGG patients from two cancer care facilities in Upper Egypt who were treated by surgery followed by RT and temozolomide (TMZ) in the period between 2007 and 2012 were reviewed. Radiotherapy schedules were either conventional RT (60 Gy in 30 fractions over 6 weeks, group A) or hypofractionated RT (45 Gy in 15 fractions over 3 weeks, group B) or hyperfractionated RT (64.8 Gy in, 1.2 Gy/fraction, 2 fractions/day, group C) with ± concurrent TMZ and adjuvant TMZ. Progression-free survival (PFS) and overall survival (OS) of patients after receiving the different types of RT treatment were evaluated. Results: Forty-eight patients with grade III or IV HGG were identified. They were classified into 3 groups (A, B and C) that included 17, 16 and 15 patients, respectively. The median PFS were 6, 9 and 8 months (p= 0.354) and the median OS were 11, 12 and 14 (p= 0.760) for group A, B and C, respectively. Late RT toxicity was not different between the 3 groups. Conclusion: The three radiation schedules had a similar efficacy in adult HGG patients.

It Is shown in this paper that, once the problem of designing dynamically optimal mechanisms is formulated as a constrained minimisation problem, genetic algorithms provide a procedure for solving this design problem which is very powerful but also very simple. These general results are illustrated by the genetic optimisation of a particular four-bar linkage that was previously optimised non-genetlcally. However, It is pointed out that the genetic design methodology described in this paper can in principle be used to minimise any desired combination of forces and couples in any mechanism.