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  1. Radiation and temperature effects on conductivity properties of PVA-KOH-PC composite
    Mohd Asri MT, Elias S, Iskandar SM, Abd Halim S, Jumiah H, Zaki AR, et al.
    Med J Malaysia, 2004 May;59 Suppl B:139-40.
    PMID: 15468857
    The aim of this work was to study radiation and the effects of temperature on conductivity properties of polyvinyl alcohol (PVA)-based potassium hydroxide (KOH) and propylene carbonate (PC), where the ionic conduction preferentially occurs in the amorphous phase by free radicals ions through gamma-irradiation. Alkaline composite polymer electrolyte (ACPE) consisting of PVA, KOH and PC of different concentration ratios were prepared by solvent-casting technique. The ACPE were irradiated with different doses from 5 kGy up to 200 kGy. The conductivity properties of the electrolyte films were measured at different frequencies in the range 20 Hz to 1 MHz using LCR meter. The results showed that the conductivity properties were dependent on the radiation dose, temperature and the concentration of the polymer blends.
    Matched MeSH terms: Dose-Response Relationship, Radiation; Electrolytes/radiation effects*; Hydroxides/radiation effects*; Polymers/radiation effects*; Polyvinyl Alcohol/radiation effects*; Propane/radiation effects*; Potassium Compounds/radiation effects*
  2. Fulltext Structural and optical properties of lead-boro-tellurrite glasses induced by gamma-ray
    Mustafa IS, Kamari HM, Yusoff WM, Aziz SA, Rahman AA
    Int J Mol Sci, 2013;14(2):3201-14.
    PMID: 23380963 DOI: 10.3390/ijms14023201
    Spectrophotometric studies of lead borotellurite glasses were carried out before and after gamma irradiation exposure. The increasing peak on the TeO(4) bi-pyramidal arrangement and TeO(3+1) (or distorted TeO(4)) is due to augmentation of irradiation dose which is attributed to an increase in degree of disorder of the amorphous phase. The structures of lead tellurate contain Pb(3)TeO(6) consisting of TeO(3) trigonal pyramid connected by PbO(4) tetragonal forming a three-dimensional network. The decrease of glass rigidity is due to irradiation process which is supported by the XRD diffractograms results. The decreasing values of absorption edge indicate that red shift effect occur after irradiation processes. A shift in the optical absorption edge attributed to an increase of the conjugation length. The values of optical band gap, E(opt) were calculated and found to be dependent on the glass composition and radiation exposure. Generally, an increase and decrease in Urbach's energy can be considered as being due to an increase in defects within glass network.
    Matched MeSH terms: Radiation Exposure; Radiation Dosage
  3. Fulltext Low-cost commercial borosilicate glass slides for passive radiation dosimetry
    Abdul Sani SF, Othman MHU, Alqahtani A, Almugren KS, Alkallas FH, Bradley DA
    PLoS One, 2020;15(12):e0241550.
    PMID: 33378398 DOI: 10.1371/journal.pone.0241550
    For x- and gamma- irradiations delivering entrance doses from 2- up to 1000 Gy to commercial 1.0 mm thick borosilicate glass microscope slides, study has been made of their thermoluminescence yield. With an effective atomic number of 10.6 (approximating bone equivalence), photon energy dependency is apparent in the low x-ray energy range, with interplay between the photoelectric effect and attenuation. As an example, over the examined dose range, at 120 kVp the photon sensitivity has been found to be some 5× that of 60Co gamma irradiations, also with repeatability to within ~1%. The glow-curves, taking the form of a single prominent broad peak, have been deconvolved yielding at best fit a total of five peaks, the associated activation energies and frequency factors also being obtained. The results indicate borosilicate glass slides to offer promising performance as a low-cost passive radiation dosimeter, with utility for both radiotherapy and industrial applications.
    Matched MeSH terms: Radiation Oncology; Radiation Dosimeters
  4. Fulltext Investigation of different exposure settings for image quality and entrance skin dose
    Nurshuhada Ali, Zafri Azran Abdul Majid, Mohd Syahriman Mohd Azmi
    International Journal of Allied Health Sciences, 2018;2(2):329-338.
    MyJurnal
    The ideal imaging system that is providing a good quality image of minimal radiation dose. There are many parameters that influenced image quality and radiation dose on clinical radiography. This study has identified some of the problems whereby there are practitioners do not select the proper size of image receptor (IR) and collimation during the examination. The re-usable of the IR and imaging plate also need to be concerned whether multiple exposures may affect the image
    quality or not. The purpose of this study is to investigate the effect of different exposure settings; kVp, mAs, collimation field sizes and different IR’ sizes for image quality and radiation dose. Methods: The wall-mounted x-ray machine act as a sources of radiation which exposed the acrylic cylinder that placed over the IR. The examination is repeated with different kVp, mAs, collimation field sizes and IR’s sizes. The source to image distance (SID) is fixed to 100 cm distance and put Nano dot dosimeter similar level with the top of acrylic to measure the dose. The result analysed by using software ImageJ to measure the Contrast to Noise Ratio (CNR). Results: The percentage of CNR1 and CNR2 reduced as the kVp is increased from (CNR1=77.25, CNR2=64.45), (CNR1=73.47, CNR2=61.22) and (CNR1=62.80, CNR2=57.32) for 50 kVp, 75 kVp and 100 kVp respectively and fluctuate when mAs increased. The CNR and entrance skin dose (ESD) shows higher when x-ray beam collimate according to IR’s size. Conclusions: Overall, the manipulative effect of exposure settings on image quality and ESD shows some positive results. The result also shows inconsistent readings in the CNR and ESD. The percentage of CNR decreased when kVp increases and slightly fluctuate when mAs increased. The ESD reading depicts higher when the kVp and mAs increase as well as when x-ray beam collimated according to IR’s sizes.
    Matched MeSH terms: Radiation Dosage; Radiation Dosimeters
  5. Fulltext Radiotracer injector: an industrial application (RIIA)
    Noraishah, O., Mohd Arif, H., Fadil Ismail, Nurliyana Abdullah, Mior Ahmad Khusaini, Mohamad Rabaie, S., et al.
    Journal of Nuclear and Related Technologies, 2011;2011(2):100-104.
    MyJurnal
    The radiotracer injector is meant for transferring liquid radiotracer in the system for industrial radiotracer application with minimal radiation exposure to the operator. The motivation of its invention is coming from the experience of the workers who are very concern about the radiation safety while handling with the radioactive source. The idea ensuring the operation while handling the radioactive source is fast and safe without interrupting the efficiency and efficacy of the process. Thus, semi automated device assisting with pneumatic technology is applied for its invention.
    Matched MeSH terms: Radiation Exposure; Radiation
  6. Fulltext A Miniaturized Antenna with Negative Index Metamaterial Based on Modified SRR and CLS Unit Cell for UWB Microwave Imaging Applications
    Islam MM, Islam MT, Samsuzzaman M, Faruque MRI, Misran N, Mansor MF
    Materials (Basel), 2015 Jan 23;8(2):392-407.
    PMID: 28787945 DOI: 10.3390/ma8020392
    A miniaturized antenna employing a negative index metamaterial with modified split-ring resonator (SRR) and capacitance-loaded strip (CLS) unit cells is presented for Ultra wideband (UWB) microwave imaging applications. Four left-handed (LH) metamaterial (MTM) unit cells are located along one axis of the antenna as the radiating element. Each left-handed metamaterial unit cell combines a modified split-ring resonator (SRR) with a capacitance-loaded strip (CLS) to obtain a design architecture that simultaneously exhibits both negative permittivity and negative permeability, which ensures a stable negative refractive index to improve the antenna performance for microwave imaging. The antenna structure, with dimension of 16 × 21 × 1.6 mm³, is printed on a low dielectric FR4 material with a slotted ground plane and a microstrip feed. The measured reflection coefficient demonstrates that this antenna attains 114.5% bandwidth covering the frequency band of 3.4-12.5 GHz for a voltage standing wave ratio of less than 2 with a maximum gain of 5.16 dBi at 10.15 GHz. There is a stable harmony between the simulated and measured results that indicate improved nearly omni-directional radiation characteristics within the operational frequency band. The stable surface current distribution, negative refractive index characteristic, considerable gain and radiation properties make this proposed negative index metamaterial antenna optimal for UWB microwave imaging applications.
    Matched MeSH terms: Radiation; Electromagnetic Radiation
  7. Fulltext Design of High Impedance Electromagnetic Surfaces for Mutual Coupling Reduction in Patch Antenna Array
    Islam MT, Alam MS
    Materials (Basel), 2013 Jan 07;6(1):143-155.
    PMID: 28809299 DOI: 10.3390/ma6010143
    A compact planar meander-bridge high impedance electromagnetic structure (MBHIES) was designed and its bandgap characteristics, mutual coupling reduction abilities were studied and compared in detail. Several parametric analyses were performed to obtain optimized design values and the transmission responses were calculated through the suspended microstrip line and waveguide simulation methods. The achieved bandgap is 2.3 GHz (2.55-4.85 GHz) with -61 dB minimum transmission coefficient level at the center frequency of 3.6 GHz. To see the effectiveness, the proposed design was inserted between a microstrip patch antenna array which operates at 3.8 GHz and whose operating bandwidth falls within the MBHIES bandgap. The surface wave suppression phenomenon was analyzed and simulated results are verified by measuring the fabricated prototypes, both are in good agreement. The configuration reduced the mutual coupling by 20.69 dB in simulation and 19.18 dB in measurement, without affecting the radiation characteristics of the array but increasing the gain slightly.
    Matched MeSH terms: Radiation; Electromagnetic Radiation
  8. Fulltext Ionizing Radiation Monitoring Technology at the Verge of Internet of Things
    Ahmad MI, Ab Rahim MH, Nordin R, Mohamed F, Abu-Samah A, Abdullah NF
    Sensors (Basel), 2021 Nov 17;21(22).
    PMID: 34833705 DOI: 10.3390/s21227629
    As nuclear technology evolves, and continues to be used in various fields since its discovery less than a century ago, radiation safety has become a major concern to humans and the environment. Radiation monitoring plays a significant role in preventive radiological nuclear detection in nuclear facilities, hospitals, or in any activities associated with radioactive materials by acting as a tool to measure the risk of being exposed to radiation while reaping its benefit. Apart from in occupational settings, radiation monitoring is required in emergency responses to radiation incidents as well as outdoor radiation zones. Several radiation sensors have been developed, ranging from as simple as a Geiger-Muller counter to bulkier radiation systems such as the High Purity Germanium detector, with different functionality for use in different settings, but the inability to provide real-time data makes radiation monitoring activities less effective. The deployment of manned vehicles equipped with these radiation sensors reduces the scope of radiation monitoring operations significantly, but the safety of radiation monitoring operators is still compromised. Recently, the Internet of Things (IoT) technology has been introduced to the world and offered solutions to these limitations. This review elucidates a systematic understanding of the fundamental usage of the Internet of Drones for radiation monitoring purposes. The extension of essential functional blocks in IoT can be expanded across radiation monitoring industries, presenting several emerging research opportunities and challenges. This article offers a comprehensive review of the evolutionary application of IoT technology in nuclear and radiation monitoring. Finally, the security of the nuclear industry is discussed.
    Matched MeSH terms: Radiation Monitoring*
  9. Fulltext High-efficiency electromagnetic energy harvesting using double-elliptical metasurface resonators
    Amer AAG, Othman N, Sapuan SZ, Alphones A, Salem AA
    PLoS One, 2023;18(12):e0291354.
    PMID: 38127949 DOI: 10.1371/journal.pone.0291354
    This study introduces a metasurface (MS) based electrically small resonator for ambient electromagnetic (EM) energy harvesting. It is an array of novel resonators comprising double-elliptical cylinders. The harvester's input impedance is designed to match free space, allowing incident EM power to be efficiently absorbed and then maximally channelled to a single load through optimally positioned vias. Unlike the previous research works where each array resonator was connected to a single load, in this work, the received power by all array resonators is channelled to a single load maximizing the power efficiency. The performance of the MS unit cell, when treated as an infinite structure, is examined concerning its absorption and harvesting efficiency. The numerical results demonstrate that the MS unit cell can absorb EM power, with near-perfect absorption of 90% in the frequency range of 5.14 GHz to 5.5 GHz under normal incidence and with a fractional bandwidth of 21%. The MS unit cell also achieves higher harvesting efficiency at various incident angles up to 60o. The design and analysis of an array of 4x4 double elliptical cylinder MS resonators integrated with a corporate feed network are also presented. The corporate feed network connects all the array elements to a single load, maximizing harvesting efficiency. The simulation and measurement results reveal an overall radiation to AC efficiency of about 90%, making it a prime candidate for energy harvesting applications.
    Matched MeSH terms: Electromagnetic Radiation*
  10. Terrestrial gamma radiation and its statistical relation with geological formation in the Mersing district, Johor, Malaysia
    Saleh MA, Ramli AT, Alajeramie Y, Suhairul H, Aliyu AS, Basri NA
    Radiat Prot Dosimetry, 2013 Sep;156(2):246-52.
    PMID: 23538891 DOI: 10.1093/rpd/nct061
    An extensive survey was carried out for gamma dose rates (GDRs) in the Mersing district, Johor, Malaysia. The average value of GDR measured in the district was found to be 140 nGy h(-1), in the range of 40-355 nGy h(-1). The mean weighted dose rate to the population, annual effective dose equivalent, collective effective dose equivalent, lifetime cancer risk were 0.836 mSv y(-1), 0.171 mSv, 1.18 × 10(1) man Sv y(-1) and 6.98 × 10(-4) Sv y, respectively. An isodose map was produced for the district. One way analysis of variance was used to test for differences due to different geological formations present in the Mersing District.
    Matched MeSH terms: Background Radiation*; Radiation Dosage; Radiation Monitoring*
  11. Terrestrial gamma radiation dose study to determine the baseline for environmental radiological health practices in Melaka state, Malaysia
    Ramli AT, Sahrone S, Wagiran H
    J Radiol Prot, 2005 Dec;25(4):435-50.
    PMID: 16340071
    Environmental terrestrial gamma radiation dose rates were measured throughout Melaka, Malaysia, over a period of two years, with the objective of establishing baseline data on the background radiation level. Results obtained are shown in tabular, graphic and cartographic form. The values of terrestrial gamma radiation dose rate vary significantly over different soil types and for different underlying geological characteristics present in the study area. The values ranged from 54 +/- 5 to 378 +/- 38 nGy h(-1). The highest terrestrial gamma dose rates were measured over soil types of granitic origin and in areas with underlying geological characteristics of an acid intrusive (undifferentiated) type. An isodose map of terrestrial gamma dose rate in Melaka was drawn by using the GIS application 'Arc View'. This was based on data collected using a NaI(Tl) scintillation detector survey meter. The measurements were taken at 542 locations. Three small 'hot spots' were found where the dose rates were more than 350 nGy h(-1). The mean dose rates in the main population areas in the mukims (parishes) of Bukit Katil, Sungai Udang, Batu Berendam, Bukit Baru and Bandar Melaka were 154 +/- 15, 161 +/- 16, 160 +/- 16, 175 +/- 18 and 176 +/- 18 nGy h(-1), respectively. The population-weighted mean dose rate throughout Melaka state is 172 +/- 17 nGy h(-1). This is lower than the geographical mean dose rate of 183 +/- 54 nGy h(-1). The lower value arises from the fact that most of the population lives in the central area of the state where the lithology is dominated by sedimentary rocks consisting of shale, mudstone, phyllite, slate, hornfels, sandstone and schist of Devonian origin which have lower associated dose rates. The mean annual effective dose to the population from outdoor terrestrial gamma radiation was estimated to be 0.21 mSv. This value is higher than the world average of 0.07 mSv.
    Matched MeSH terms: Background Radiation*; Radiation Dosage; Radiation Monitoring/methods*
  12. Ultrasound assisted lipase catalyzed synthesis of poly-6-hydroxyhexanoate
    Gumel AM, Annuar MS, Chisti Y, Heidelberg T
    Ultrason Sonochem, 2012 May;19(3):659-67.
    PMID: 22105013 DOI: 10.1016/j.ultsonch.2011.10.016
    Ultrasonic irradiation greatly improved the Candida antarctica lipase B mediated ring opening polymerization of ε-caprolactone to poly-6-hydroxyhexanoate in the ionic liquid 1-ethyl-3-methylimidazolium tetraflouroborate. Compared to the conventional nonsonicated reaction, sonication improved the monomer conversion by 63% and afforded a polymer product of a narrower molecular weight distribution and a higher degree of crystallinity. Under sonication, the polydispersity index of the product was ~1.44 compared to a value of ~2.55 for the product of the conventional reaction. With sonication, nearly 75% of the monomer was converted to product, but the conversion was only ~16% for the reaction carried out conventionally. Compared to conventional operation, sonication enhanced the rate of polymer propagation by >2-fold and the turnover number of the lipase by >3-fold.
    Matched MeSH terms: Catalysis/radiation effects; Enzyme Activation/radiation effects; Lipase/radiation effects*; Polyesters/radiation effects*; Polymers/radiation effects*; Radiation Dosage
  13. Reliability in individual monitoring service
    Mod Ali N
    Radiat Prot Dosimetry, 2011 Mar;144(1-4):90-4.
    PMID: 21147789 DOI: 10.1093/rpd/ncq454
    As a laboratory certified to ISO 9001:2008 and accredited to ISO/IEC 17025, the Secondary Standard Dosimetry Laboratory (SSDL)-Nuclear Malaysia has incorporated an overall comprehensive system for technical and quality management in promoting a reliable individual monitoring service (IMS). Faster identification and resolution of issues regarding dosemeter preparation and issuing of reports, personnel enhancement, improved customer satisfaction and overall efficiency of laboratory activities are all results of the implementation of an effective quality system. Review of these measures and responses to observed trends provide continuous improvement of the system. By having these mechanisms, reliability of the IMS can be assured in the promotion of safe behaviour at all levels of the workforce utilising ionising radiation facilities. Upgradation of in the reporting program through a web-based e-SSDL marks a major improvement in Nuclear Malaysia's IMS reliability on the whole. The system is a vital step in providing a user friendly and effective occupational exposure evaluation program in the country. It provides a higher level of confidence in the results generated for occupational dose monitoring of the IMS, thus, enhances the status of the radiation protection framework of the country.
    Matched MeSH terms: Radiation Dosage*; Radiation Monitoring/standards*; Radiation Protection/methods; Radiation Protection/standards*
  14. RESULTS OF THE JOINT IAEA/ARPANSA INTERCOMPARISON EXERCISE ON WHOLE BODY DOSEMETERS FOR PHOTONS IN ASIA AND THE PACIFIC REGION
    Rizk C, Long S, Okyar HB, Baradaran S, Al Fares E, Sangau JK, et al.
    Radiat Prot Dosimetry, 2019 Dec 31;187(4):418-425.
    PMID: 31605130 DOI: 10.1093/rpd/ncz182
    An intercomparison exercise (IC) on whole body dosemeters to determine the quantity personal dose equivalent Hp (10) in photon radiation fields was jointly organised and conducted by the International Atomic Energy Agency (IAEA) and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) for individual monitoring services (IMS) in Asia and the Pacific region. This was arranged to help the IMS in the region to achieve a more accurate dosimetry service and to improve their performance. Twenty-four IMS participated in this IC. Four sets of dosemeters were irradiated using X-ray and gamma radiation qualities at 0° and 20° angle of incidence, respectively. All the IMS provided results that were within the acceptable limits defined by the IAEA. However, only a minority of participants reported confidence intervals that included the reference dose, for each exposure scenario. For few systems, the overall performance could be significantly improved by reviewing calibration procedures.
    Matched MeSH terms: Radiation Dosage; Radiation Monitoring/standards*; Radiation Protection/standards*; Radiation Dosimeters/standards*
  15. ASSESSMENT OF NATURAL RADIOACTIVITY IN MAIZE AND ESTIMATION OF CONCOMITANT DOSE TO NIGERIAN VIA INGESTION PATHWAY
    Yarima MH, Khandaker MU, Nadhiya A, Olatunji MA
    Radiat Prot Dosimetry, 2019 Oct 01;184(3-4):359-362.
    PMID: 31089715 DOI: 10.1093/rpd/ncz115
    Uranium, thorium and potassium are the most abundant naturally occurring radioactive materials (NORMs) found in soils and other environmental media including foodstuffs. Since the human exposures to NORMs is an unavoidable phenomenon, in such a way that they can easily find their way to human being via food chain, detailed knowledge on their presence in foodstuffs is necessary to assess the radiation dose to the population. Thus, the present study concerns the assessment of natural radioactivity in maize, a staple foodstuff for Nigerian, via HPGe gamma-ray spectrometry. Activity concentrations (Bq/kg) in the maize samples were found to be in the range of 6.1 ± 0.6-8.2 ± 1.3, 2.2 ± 0.4-5.1 ± 0.7 and 288 ± 16-401 ± 24 for 226Ra, 232Th and 40K, respectively. Measured data for 226Ra and 232Th show below the world average values of 67 Bq/kg and 82 Bq/kg, respectively, while the activity of 40K exceeds the global average of 310 Bq/kg. The annual effective dose via the maize consumption was found to be far below the UNSCEAR recommended ingestion dose limit of 290 μSv/y, and the estimated lifetime cancer risk show lower than the ICRP (1991) cancer risk factor of 2.5 × 10-3 based on the additional annual dose limit of 1 mSv for general public, thus pose no adverse health risk to the Nigerian populace.
    Matched MeSH terms: Background Radiation*; Zea mays/radiation effects; Radiation Dosage; Radiation Monitoring/methods*
  16. Laser-induced changes of in vitro erythrocyte sedimentation rate
    Al Musawi MS, Jaafar MS, Al-Gailani B, Ahmed NM, Suhaimi FM
    Lasers Med Sci, 2017 Dec;32(9):2089-2095.
    PMID: 28967036 DOI: 10.1007/s10103-017-2340-5
    The study of the effects of low-level laser (LLL) radiation on blood is important for elucidating the mechanisms behind the interaction of LLL radiation and biologic tissues. Different therapy methods that involve blood irradiation have been developed and used for clinical purposes with beneficial effects. The aim of this study was to compare the effects of different irradiation protocols using a diode-pumped solid-state LLL (λ = 405 nm) on samples of human blood by measuring the erythrocyte sedimentation rate (ESR). Human blood samples were obtained through venipuncture into tubes containing EDTA as an anticoagulant. Every sample was divided into two equal aliquots to be used as an irradiated sample and a non-irradiated control sample. The irradiated aliquot was subjected to a laser beam with a wavelength of 405 nm and an energy density of 72 J/cm2. The radiation source had a fixed irradiance of 30 mW/cm2. The ESR change was observed for three different experimental protocols: irradiated whole blood, irradiated red blood cells (RBCs) samples re-suspended in non-irradiated blood plasma, and non-irradiated RBCs re-suspended in irradiated blood plasma. The ESR values were measured after laser irradiation and compared with the non-irradiated control samples. Irradiated blood plasma in which non-radiated RBCs were re-suspended was found to result in the largest ESR decrease for healthy human RBCs, 51%, when compared with RBCs re-suspended in non-irradiated blood plasma. The decrease in ESR induced by LLL irradiation of the plasma alone was likely related to changes in the plasma composition and an increase in the erythrocyte zeta potential upon re-suspension of the RBCs in the irradiated blood plasma.
    Matched MeSH terms: Blood Sedimentation/radiation effects; Dose-Response Relationship, Radiation; Erythrocyte Volume/radiation effects; Erythrocytes/radiation effects*; Plasma/radiation effects; Cell Shape/radiation effects
  17. Fulltext Watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice modulates oxidative damage induced by low dose X-ray in mice
    Mohammad MK, Mohamed MI, Zakaria AM, Abdul Razak HR, Saad WM
    Biomed Res Int, 2014;2014:512834.
    PMID: 24877107 DOI: 10.1155/2014/512834
    Watermelon is a natural product that contains high level of antioxidants and may prevent oxidative damage in tissues due to free radical generation following an exposure to ionizing radiation. The present study aimed to investigate the radioprotective effects of watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice against oxidative damage induced by low dose X-ray exposure in mice. Twelve adult male ICR mice were randomly divided into two groups consisting of radiation (Rx) and supplementation (Tx) groups. Rx received filtered tap water, while Tx was supplemented with 50% (v/v) watermelon juice for 28 days ad libitum prior to total body irradiation by 100 μGy X-ray on day 29. Brain, lung, and liver tissues were assessed for the levels of malondialdehyde (MDA), apurinic/apyrimidinic (AP) sites, glutathione (GSH), and superoxide dismutase (SOD) inhibition activities. Results showed significant reduction of MDA levels and AP sites formation of Tx compared to Rx (P < 0.05). Mice supplemented with 50% watermelon juice restore the intracellular antioxidant activities by significantly increased SOD inhibition activities and GSH levels compared to Rx. These findings may postulate that supplementation of 50% watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice could modulate oxidative damage induced by low dose X-ray exposure.
    Matched MeSH terms: Organ Specificity/radiation effects; Radiation Injuries, Experimental/drug therapy*; Radiation Injuries, Experimental/metabolism*; Radiation-Protective Agents/pharmacology*; Radiation-Protective Agents/chemistry; Oxidative Stress/radiation effects
  18. Fulltext Measurement of extremely low frequency (ELF) magnetic flux in the vicinity of the overhead high voltage transmission line in Universiti Kebangsaan Malaysia
    Faizal Mohamed, Irman Abdul Rahman, Ngu, Thieng Kui, Syazwani Mohd Fadzil, Firdaus Pozi, Amran Ab. Majid, et al.
    Journal of Nuclear and Related Technologies, 2017;14(2):1-10.
    MyJurnal
    Electricity has become one of the necessities for human daily activities. The presence of electric
    current produces electromagnetic fields (EMF) at extremely low frequency (ELF). The problem arises
    when scientists suggests a possible connection between ELF exposure to human health and safety.
    Concerned about the safety and health of students and staff, Universiti Kebangsaan Malaysia (UKM)
    took the initiative to identify possible ELF sources and measure their exposure in various locations
    around the UKM main campus in Bangi. This paper reports the results obtained from the monitoring
    of the magnetic flux density at three identified locations in the vicinity of the overhead high-voltage
    transmission line which transverses the university compound and compare the maximum value results
    with the exposure limit suggested by the International Committee on Non Ionising Radiation
    Protection (ICNIRP) for ELF. Measurements were done with an (Extech) Three Axis
    Electromagnetic Field (EMF) Meter (Model 430826) to determine the magnetic flux density. The
    lateral profile method was applied as the standard measurement methodology. Results showed that the
    maximum value of the magnetic flux density was 12.5 mG, which is below the suggested ICNIRP
    public exposure limit of 1000 mG, or in percentage ratio, 1.25% of ICNIRP public exposure limit.
    Results from the statistical Kruskal-Wallis test showed that there is a significant difference in the
    distributions of the magnetic flux densities at the different locations (P < 0.05). In conclusion, the
    measured locations are still safe for people in short-term exposure. However, long-term exposure
    measurements still need to be done to provide concrete data on the ELF-emission levels in UKM.
    Matched MeSH terms: Radiation Exposure; Radiation, Ionizing; Radiation, Nonionizing
  19. Fatigue following head and neck cancer radiotherapy: a systematic review of dose correlates
    Leong WC, Manan HA, Hsien CCM, Wong YF, Yahya N
    Support Care Cancer, 2024 Jun 26;32(7):460.
    PMID: 38918218 DOI: 10.1007/s00520-024-08655-4
    INTRODUCTIONS: Radical radiotherapy (RT) is the cornerstone of Head and Neck (H&N) cancer treatment, but it often leads to fatigue due to irradiation of brain structures, impacting patient quality of life.

    OBJECTIVE: This study aimed to systematically investigate the dose correlates of fatigue after H&N RT in brain structures.

    METHODS: The systematic review included studies that examined the correlation between fatigue outcomes in H&N cancer patients undergoing RT at different time intervals and brain structures. PubMed, Scopus, and WOS databases were used in the systematic review. A methodological quality assessment of the included studies was conducted following the PRISMA guidelines. After RT, the cohort of H&N cancer patients was analyzed for dose correlations with brain structures and substructures, such as the posterior fossa, brainstem, cerebellum, pituitary gland, medulla, and basal ganglia.

    RESULT: Thirteen studies meeting the inclusion criteria were identified in the search. These studies evaluated the correlation between fatigue and RT dose following H&N RT. The RT dose ranged from 40 Gy to 70 Gy. Most of the studies indicated a correlation between the trajectory of fatigue and the dose effect, with higher levels of fatigue associated with increasing doses. Furthermore, five studies found that acute and late fatigue was associated with dose volume in specific brain structures, such as the brain stem, posterior fossa, cerebellum, pituitary gland, hippocampus, and basal ganglia.

    CONCLUSION: Fatigue in H&N RT patients is related to the radiation dose received in specific brain areas, particularly in the posterior fossa, brain stem, cerebellum, pituitary gland, medulla, and basal ganglia. Dose reduction in these areas may help alleviate fatigue. Monitoring fatigue in high-risk patients after radiation therapy could be beneficial, especially for those experiencing late fatigue.

    Matched MeSH terms: Brain/radiation effects; Dose-Response Relationship, Radiation
  20. Fulltext Stimulatory effects of gamma irradiation on phytochemical properties, mitotic behaviour, and nutritional composition of sainfoin (Onobrychis viciifolia Scop.)
    Mohajer S, Taha RM, Lay MM, Esmaeili AK, Khalili M
    ScientificWorldJournal, 2014;2014:854093.
    PMID: 25147870 DOI: 10.1155/2014/854093
    Sainfoin (Onobrychis viciifolia Scop. Syn. Onobrychis sativa L.) is a bloat-safe forage crop with high levels of tannins, which is renowned for its medicinal qualities in grazing animals. Mutagenesis technique was applied to investigate the influence of gamma irradiation at 30, 60, 90, and 120 Gy on mitotic behavior, in vitro growth factors, phytochemical and nutritional constituents of sainfoin. Although a percentage of plant necrosis and non-growing seed were enhanced by irradiation increment, the germination speed was significantly decreased. It was observed that gamma irradiated seeds had higher value of crude protein and dry matter digestibility compared to control seeds. Toxicity of copper was reduced in sainfoin irradiated seeds at different doses of gamma rays. Anthocyanin content also decreased in inverse proportion to irradiation intensity. Accumulation of phenolic and flavonoid compounds was enhanced by gamma irradiation exposure in leaf cells. HPLC profiles differed in peak areas of the two important alkaloids, Berberine and Sanguinarine, in 120 Gy irradiated seeds compared to control seeds. There were positive correlations between irradiation dose and some abnormality divisions such as laggard chromosome, micronucleus, binucleated cells, chromosome bridge, and cytomixis. In reality, radiocytological evaluation was proven to be essential in deducing the effectiveness of gamma irradiation to induce somaclonal variation in sainfoin.
    Matched MeSH terms: Fabaceae/radiation effects*; Mitosis/radiation effects*; Seeds/radiation effects
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