Four electrode measurement (4EM) systems have been used to measure conductivity in tissue where electrode polarization would cause unacceptable inaccuracy in measurement results and where directional measurement of conductivity is required Less polarization than a two-electrode measurement system where the current is applied by the same electrodes that measures the potential and directional measurement as opposed to a coaxial measurement system that measures bulk conductivity but gives no information about direction. ( 1 , 2 , 3) . The system
the tissue engineered constructs. However, these methods such as histology staining, are destructive and time-consuming and require fixing and cutting the tissue cultures ( 6 ).
Therefore, there is a need for real-time and noninvasive monitoring techniques to evaluate the quality of the tissue engineered constructs before implanting them in the body, without the need to use fluorescents or radioactive labels or destructive methods. This in addition, would reduce the number of animals required for this purpose ( 5 , 6 ).
Martina Sammer, Bob Laarhoven, Ernest Mejias, Doekle Yntema, Elmar C. Fuchs, Gert Holler, Georg Brasseur and Ernst Lankmayr
as a static capacitor. The dielectric properties of biological cells and their different components (cell wall, membranes and cytoplasm) were summarized by Markx and Davey [ 4 ]. Over the last couple of decades a lot of research was done on the impedance of cell suspensions, in which a relationship between capacitance and viable cell number was reported [ 5 , 6 , 7 , 8 ]. Fehrenbach et al. [ 5 ] used online capacitive measurements for biomass estimation of Saccaromyces cerevisiae , Pitchia pastoris and Streptomyces virginiae in suspension culture. In their
Piotr Ulkowski, Wojciech Bulski and Barbara Gwiazdowska
Reports Series, Vienna, 2000; No TRS 398.
IAEA. Calibration of reference dosimeters for external beam radiotherapy. Technical Reports Series, Vienna, 2009; No TRS 469.
IAEA. Dosimetry in diagnostic radiology. An international code of practice. Technical Reports Series, Vienna, 2007; No TRS 457.
ISO/IEC/OIML/BIPM, Guide to the expression of uncertainty in measurements. 1995.
 Verdun FR, Racine D, Ott JG, et al. Image quality in CT: From physical measurements to model observers. Phys Med. 2015;31(8):823-843.
 International Atomic Energy Agency. Status of computed tomography: Dosimetry for wide cone beam scanners. IAEA-Human Health Reports No 5. 2011.
 Kalender WA, Seissler W, Klotz E, Vock P. Spiral volumetric CT with single-breath-hold technique, continuous transport, and continuous scanner rotation. Radiology. 1990;176(1):181-183.
 McCollough CH, Zink FE. Performance evaluation of a
Osko J. Spectrometric Measurements of the Radioactive Isotopes Uptake in Thyroid [Phd thesis]. [Warsaw]: Warsaw University of Technology, Faculty of Mechatronics; 2008. 111 p.
Osko J, Golnik N, Pliszczynski T. Spectrometric measurements of iodine and technetium activity in thyroid. Nucl Instrum Methods Phys Res A. 2007; 580 : 578-581.
Osko J, Golnik N, Pliszczynski T. Uncertainties in determination of 131 I activity in thyroid gland. Radiat Prot Dosim. 2007 Jul
Today, to establish a diagnosis, the patient must undergo a biopsy followed by histopathological diagnosis, which causes unnecessary cost, patient trauma, and time delay to obtain a diagnosis. However, the metastases can be discovered by diffuse reflectance spectroscopy, which is a simple method that investigates the light distribution within tissue. The theme of this paper is the use of diffuse reflectance spectroscopy (DRS) to determine the optical spectrum of hamster specimen’s tissue and to differentiate biological changes due to laser irradiation (scattering, and cell changes) under the skin. DRS measurements were made on healthy and malignant tissue to diagnose the stages of cancer formation using a fiber-optic probe. The results show that malignant tissue is characterized by a significant decrease in diffuse reflectance spectrum compared to normal tissue.
Suffian Mohamad Tajudin and Adila Hanim Aminordin Sabri
-Contacting System to Online Measure the Radiotracer Concentration in Blood. Prog Nucl Sci Technol. 2014;4:290-293.
 Hubbell JH, Seltzer SM. X-Ray Mass Attenuation Coefficients. NISTIR 5632. https://www.nist.gov/pml/x-ray-mass-attenuation-coefficients .
 Berger MJ, Hubbell JH, Seltzer SM, et al. XCOM: Photon Cross Sections Database. NBSIR 87-3597. http://www.nist.gov/pml/data/xcom/index.cfm .
 Pawar PP. Measurement of Mass and Linear Attenuation Coefficients of Gamma-Rays of AL for 514, 662 and 1280 keV Photons. J Chem Pharm Res. 2011;3(4): 899
Karthick Raj Mani, Muhtasim Aziz Muneem, Nazneen Sultana, Tanjina Hossain, Tabinda Basharat, Saumen Basu and Ramaa Lingaiah
of the uterine cervix. Int J Radiat Oncol Biol Phys. 1995;32(5):1289-1300,
 Hasselle MD, Rose BS, Kochanski JD, et al. Clinical Outcomes of Intensity-Modulated Pelvic Radiation Therapy for Carcinoma of the Cervix. Int J Radiat Oncol Biol Phys. 2011;80(5):1436-1445.
 Ng J, Shuryak I. Minimizing second cancer risk following radiotherapy: current perspectives. Cancer Manag Res 2014; 7 :1-11.
 International Commission on Radiation Units and Measurements. Prescribing, recording, and reporting photon beam intensity-modulated radiation therapy
, Barros S, Cardoso S, et al. A dosimetric study of prostate brachytherapy using Monte Carlo simulations with a voxel phantom, measurements and a comparison with a treatment planning procedure. Radiat Protect Dosim. 2015;165(1-4):482-487.
 Davis BJ, Horwitz EM, Lee WR, et al. American Brachytherapy Society consensus guidelines for transrectal ultrasound-guided permanent prostate brachytherapy. Brachytherapy. 2012;11:6-19.
 Wang C, Chen Z, Sun W, et al. Palliative treatment of pelvic bone tumors using radioiodine ( 125 I) brachytherapy. World J Surg