In recent years, a method for designing radiotherapy boluses using 3D printing technology has been established in the West Pomeranian Oncology Centre in Szczecin, Poland. The aim of the present study was to investigate whether the ionising radiation used in radiotherapy affects the physical properties of the printing material. Particularly, the purpose of this study was to determine the effect of a 60 Gy X-ray radiation dose on the hardness and dimensions of 3D-printed boluses. Four cuboids were printed on a Zortrax M200 printer with acrylonitrile–butadiene–styrene (ABS) polymer. All printed samples were exposed to 60 Gy of X-ray radiation delivered by a medical accelerator. After irradiation, changes in the hardness (using Vickers test) and dimensions of the prints were measured. The therapeutic X-ray dose had a minimal effect on the dimensions of the printed samples, resulting in a maximum contraction of only 0.4%. Changes of the hardness were not statistically significant. In conclusion, regarding the radiotherapy planning process, the application of this therapeutic X-ray dose does not significantly influence the hardness and dimensions of ABS-printed boluses.

phantoms of biological tissues are materials that mimic the properties of real tissues. this study shows the development of phantoms with nanodiamond particles for calibration of T1 relaxation time in magnetic resonance imaging. Magnetic resonance imaging (MRi) is a commonly used and non-invasive method of detecting pathological changes inside the human body. nevertheless, before a new MRi device is approved for use, it is necessary to calibrate it properly and to check its technical parameters. in this article, we present phantoms of tissue with diamond nanoparticles dedicated to magnetic resonance calibration. the method of producing phantoms has been described. As a result of our research, we obtained phantoms that were characterized by the relaxation time T1 the same as the relaxation time of the human tissue T1 = 810.5 ms. Furthermore, the use of diamond nanoparticles in phantoms allowed us to tune the T1 value of the phantoms which open the way to elaborated phantoms of other tissues in the future.Magnetic resonance imaging (MRI), is a non-invasive technique for creating detailed images of the human body. This method allows for obtaining high-resolution cross-sectional images of tissue in any surfaces. Therefore now is a widely available, powerful instrument for non-invasive imaging of soft tissues better then X-rays, computerized tomography scans or ultrasound 1-3 . Chronic liver diseases represent an important global health problem.MRI is a technique which plays a significant role in diagnosis of different liver disorders. The MRI investigation can show and confirm diffuse liver damage due to metabolic diseases or cirrhosis. Furthermore, MRI plays an important role in differentiation in primary hepatic malignancies or metastatic diseases 4 . The parameters characteristic for a sample investigated by the means of MRI are longitudinal relaxation time T1 and transverse relaxation time T2, which directly depend on the biophysical structure of the test substance and the biochemical environment 5 . The study of relaxation times and their dependence on the magnetic field, temperature, pH, etc. provides valuable information on the structure and molecular dynamics of the substance. A significant amount of biological tissue phantoms used for an MRI scanner calibration is created to examine the scanner's technical parameters [6][7][8][9][10][11][12][13] . Phantoms used to calibrate relaxation times are scarce. The few phantoms dedicated to the calibration of relaxation times are mainly oil based or water based (e.g. aqueous solutions of inorganic acid salts 12,14-17 ). Due to their liquid state, the calibration process is more time-consuming because the liquid must stabilize before the measurement can start. Relaxation agents such as gadolinium trichloride, which were found to enable adjustment of T 1 relaxation time, are toxic, therefore their use for biomedical applications is excluded 18 .

Introduction: This study aimed to determine whether the degradation of ascorbic acid in aqueous solutions could be used to compare the filtration efficiency of various household water filter jugs.Materials and methods: Based on absorbance measurements of ascorbic acid, a new water quality coefficient (WQC) parameter was defined. Differences between the WQC were determined for 4 different water filters commonly used in household water filter jugs in Poland. In addition, correlations between the WQC, the amount of filtered water (AFW), and a number of other parameters were examined for all 4 filters.Conclusions: Significant differences were found in WQC among the 4 filters. A decreasing efficiency of calcium ion removal from the water was observed with the ongoing use of all 4 filter cartridges. Overall, this method could be a sensitive, simple, fast, eco-friendly, and relatively inexpensive tool for determining the effectiveness of water purification in household water filter jugs, which of course requires further research.

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The primary purpose of this study was to develop a laboratory photonic set-up for characterisation of homogeneity of gel phantoms for calibration of a magnetic resonance. In this system optical coherence tomography allows the detection of micro- and macroscopic heterogeneities of a structure. The set-up was used to perform measurements of agar and agar-carrageenan gels, which are the basis for more complex phantoms for magnetic resonance calibration. Obtained results were compared with magnetic resonance tomography methods used to detect macroscopic spatial differences in composition and heterogeneities in phantoms. Full Text: PDF ReferencesPrice R. R. et al., Quality assurance methods and phantoms for magnetic resonance imaging: report of AAPM nuclear magnetic resonance Task Group No. 1., Med Phys. 1990 Mar-Apr;17(2):287-95. CrossRef Tofts P.S., QA: quality assurance, accuracy, precision and phantoms. Chapter 3 in Tofts P.S. (ed.) Quantitative MRI of the brain: measuring changes caused by disease. Chichester: John Wiley, 55-81. ISBN: 0-470-84721-2 CrossRef Wróbel M., Popov A., Bykov A., Tuchin V.V., Jędrzejewska-Szczerska M., Nanoparticle-free tissue-mimicking phantoms with intrinsic scattering, Biomedical Optic Express, vol. 7(6), 2088-2094 (2016). CrossRef Feder I., Wróbel M., Duadi H., Jędrzejewska-Szczerska M., Fixler D., Experimental results of full scattering profile from finger tissue-like phantom, Biomedical Optic Express, vol. 7 (11), 4695-4701 (2016). CrossRef Wróbel M. S. et al., Use of optical skin phantoms for pre-clinical evaluation of laser efficiency for skin lesion therapy, Journal of Biomedical Optics, 20(8), 20(8):085003 (2015). CrossRef Wróbel M .S. et al., Multi-layered tissue head phantoms for noninvasive optical diagnostics, Journal of Innovative Optical Health Sciences, 8(3), 1541005-1÷1541005-10 (2015). CrossRef Hellerbach A, Schuster V, Jansen A, Sommer J., MRI Phantoms - Are There Alternatives to Agar?, Plos One, 2013;8(8), ARTN e70343. CrossRef Almazrouei N. K., Newton M. I., Dye E. R., Morris R. H., Novel food-safe spin-lattice relaxation time calibration samples for use in magnetic resonance sensor development, Proceedings 2018, 2, 122. CrossRef Ohno S. et al., Production of a Human-Tissue-Equivalent MRI Phantom: Optimization of Material Heating, Magn Reson Med Sci. 2008;7(3):131-40. CrossRef Choma M. A., SarunicM. V., Yang C., Izatt J. A., Sensitivity advantage of swept source and Fourier domain optical coherence tomography, Opt. Express 11, 2183-2189 (2003). CrossRef Strąkowski M. R., Głowacki M., Kamińska A., Sawczak M., Gold nanoparticles evaluation using functional optical coherence tomography, Proc. SPIE 10053, Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXI, 1005336 (17 February 2017). CrossRef