The detecting module based on gallium arsenide detectors in digital mammography
Success in early breast cancer diagnostic depends on technical characteristics of detecting module. The most important is detector resolution. In this paper we represent quantum-sensitive detectors of X-rays based on GaAs for digital mammography systems. Electron/hole pairs created by radiation, which interact with the GaAs detectors, result current pulse at the detector output and specialist can see image immediately. Progress in development and investigation of a semiconductor material capable to provide reliable registration of single quanta of roentgen radiation. It is supposed to reduce patient radiation doze. At the same time, the system delivers high-quality images with resolution, contrast and clarity equal to film X-rays, or even better. Main advantages which can be achieved by using these detectors are analyzed.
THE DOSE AND IMAGE QUALITY IN MAMMOGRAPHY PRACTICE IN FINLAND
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Rational Design, Synthesis and Evaluation of γ-CD-Containing Cross-Linked Polyvinyl Alcohol Hydrogel as a Prednisone Delivery Platform
This study describes the in-silico rational design, synthesis and evaluation of cross-linked polyvinyl alcohol hydrogels containing γ-cyclodextrin (γ-CDHSAs) as platforms for the sustained release of prednisone (PDN). Through in-silico studies using semi-empirical quantum mechanical calculations, the effectiveness of 20 dicarboxylic acids to generate a specific cross-linked hydrogel capable of supporting different amounts of γ-cyclodextrin (γ-CD) was evaluated. According to the interaction energies calculated with the in-silico studies, the hydrogel made from PVA cross-linked with succinic acids (SA) was shown to be the best candidate for containing γ-CD. Later, molecular dynamics simulation studies were performed in order to evaluate the intermolecular interactions between PDN and three cross-linked hydrogel formulations with different proportions of γ-CD (2.44%, 4.76% and 9.1%). These three cross-linked hydrogels were synthesized and characterized. The loading and the subsequent release of PDN from the hydrogels were investigated. The in-silico and experimental results showed that the interaction between PDN and γ-CDHSA was mainly produced with the γ-CDs linked to the hydrogels. Thus, the unique structures and properties of γ-CDHSA demonstrated an interesting multiphasic profile that could be utilized as a promising drug carrier for controlled, sustained and localized release of PDN.