Johan Andoyo Effendi Noor
Unknown Affiliation

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

Effects of Quadrifide Sterculia R. Br Extract on Potential of Membrane of Oreochromis Niloticus Egg Cell Resulting from Pb Contamination Fetronela Rambu Bobu; Chomsin Sulistya Widodo; Johan Andoyo Effendi Noor
Natural B, Journal of Health and Environmental Sciences Vol 3, No 4 (2016)
Publisher : Natural B, Journal of Health and Environmental Sciences

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (397.152 KB) | DOI: 10.21776/ub.natural-b.2016.003.04.4

Abstract

The effect of faloak (Sterculia quadrifida R.Br.) extract to the cell membrane potentials of tilapia (Oreochromis nilaticus) egg in contaminated water lead was studied. The cell membrane potential of tilapia egg was measured by a microelectrode connected to a Picoscope. The result showed that increasing of the Pb consentration caused decreasly of the membrane potential. Faloak extraction in contaminated water raised the membrane potential value. The concentration of faloak extract with the impact of raising the cell membrane potential of tilapia egg that have been contaminated by Pb is 0,8 mg. It seems that the antioxidant of faloak extract can reduce pollution rate.
RADIOLOGICAL CHARACTERISTICS OF 3D-PRINTED PETG AND TPU AT DIFFERENT INFILL PERCENTAGES FOR BREAST CANCER RADIOTHERAPY BOLUS Abrar, Luthfia Aqila; Sri Herwiningsih; Johan Andoyo Effendi Noor; Faisal Ahlan Rizaldi; Fatimah Kunti Hentihu
Indonesian Physical Review Vol. 9 No. 1 (2026)
Publisher : Universitas Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/ipr.v9i1.531

Abstract

Skin-sparing effect causes the radiation dose at a certain depth to be higher than at the skin surface. A tissue-equivalent material namely bolus is required to increase the radiation dose to the skin surface. Conventional bolus is widely used, it poorly conforms to irregular surface, leading to air gaps and compromising dose distribution accuracy. The three-dimensional (3D) printing technology enables the fabrication of 3D-printed boluses to minimize the air gap in conventional bolus applications. In addition, 3D printing is allowed to modify its infill percentage and infill patterns, minimizing both printing time and material usage but resulting in different radiological and dosimetric characteristics. Therefore, it is crucial to evaluate the radiological characteristics of 3D-printed bolus before its application in breast cancer radiotherapy. In this study, the radiological characteristics of 3D-printed Polyethylene Terephthalate Glycol (PETG) and Thermoplastic Polyurethane (TPU) boluses at different infill percentages have been evaluated. This research utilized eight plate-shaped 3D-printed bolus samples with dimensions of 12 cm × 12 cm × 1 cm, at the infill percentages of 20%, 40%, 60%, and 80%. Each bolus sample was scanned using a CT-Simulator to determine its Hounsfield Unit (HU) values and linear attenuation coefficients. The obtained HU values were compared with the HU values of human tissues. The results indicate that both 3D-printed PETG and TPU boluses demonstrate similar equivalency to adipose tissue. Consequently, based on radiological evaluation, PETG and TPU materials are suitable for use in fabricating 3D-printed bolus for breast cancer radiotherapy application.