An investigation of the dose distribution effect related with collimator angle in volumetric arc therapy of prostate cancer

To investigate the dose-volume variations of planning target volume (PTV) and organ at risks (OARs) in eleven prostate cancer patients planned with single and double arc volumetric modulated arc therapy (VMAT) when varying collimator angle. Single and double arc VMAT treatment plans were created using Monaco5.0 (R) with collimator angle set to 0 degrees. All plans were normalized 7600 cGy dose to the 95% of clinical target volume (CTV) volume. The single arc VMAT plans were reoptimized with different collimator angles (0 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, and 90 degrees), and for double arc VMAT plans (0-0 degrees, 15 degrees-345, 30-330 degrees, 45-315 degrees, 60-300 degrees, 75-285 degrees, 90-270 degrees) using the same optimization parameters. For the comparison the parameters of heterogeneity index (HI), dose-volume histogram and minimum dose to the 95% of PTV volume (D95 PTV) calculated and analyzed. The best plans were verified using 2 dimensional ion chamber array IBA Matrixx (R) and three-dimensional IBA Compass (R) program. The comparison between calculation and measurement were made by the gamma-index (3%/3 mm) analysis. A higher D95 (PTV) were found for single arc VMAT with 15 degrees collimator angle. For double arc, VMAT with 60-300 degrees and 75-285 degrees collimator angles. However, lower rectum doses obtained for 75-285 degrees collimator angles. There was no significant dose difference, based on other OARs which are bladder and femur head. When we compared single and double arc VMAT's D95 (PTV), we determined 2.44% high coverage and lower HI with double arc VMAT. All plans passed the gamma-index (3%/3 mm) analysis with more than 97% of the points and we had an average gamma-index for CTV 0.36, for PTV 0.32 with double arc VMAT. These results were significant by Wilcoxon signed rank test statistically. The results show that dose coverage of target and OAR's doses also depend significantly on the collimator angles due to the geometry of target and OARs. Based on the results we have decided to plan prostate cancer patients in our clinic with double arc VMAT and 75 degrees-285 degrees collimator angles

Preparation, spectral characterization, ESR measurements and DFT calculations of Schiff base copper(II) complex

BULDURUN, Kenan/0000-0002-2462-7006The title compound ([CuClL(H2O)]center dot 2H(2)O) were synthesized. The copper(II) complex in square planar geometry were identified by using elemental analysis, magnetic susceptibility, mass spectra, FT-IR, UV-Vis. and ESR techniques. DFT calculations at the UB3LYP/LANL2DZ level of theory were conducted to obtain vibrational and electronic properties of the copper(II) complex. Vibrational assignments of the observed infrared spectra of title compound were carried out based on the calculated potential energy distributions (PEDs). The sensitive measurement results indicated that the observed values were reasonable. The energy values were determined to describe electronic properties of the title molecules. Furthermore, NBO analysis was performed to analyze the hyper-conjugative stability of the molecule, molecular orbital interaction and charge delocalization

Preparation, spectral characterization, ESR measurements and DFT calculations of Schiff base copper(II) complex

BULDURUN, Kenan/0000-0002-2462-7006The title compound ([CuClL(H2O)]center dot 2H(2)O) were synthesized. The copper(II) complex in square planar geometry were identified by using elemental analysis, magnetic susceptibility, mass spectra, FT-IR, UV-Vis. and ESR techniques. DFT calculations at the UB3LYP/LANL2DZ level of theory were conducted to obtain vibrational and electronic properties of the copper(II) complex. Vibrational assignments of the observed infrared spectra of title compound were carried out based on the calculated potential energy distributions (PEDs). The sensitive measurement results indicated that the observed values were reasonable. The energy values were determined to describe electronic properties of the title molecules. Furthermore, NBO analysis was performed to analyze the hyper-conjugative stability of the molecule, molecular orbital interaction and charge delocalization