Displaying publications 41 - 60 of 133 in total

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  1. Taheri S, Abdullah TL, Karimi E, Oskoueian E, Ebrahimi M
    Int J Mol Sci, 2014;15(7):13077-90.
    PMID: 25056545 DOI: 10.3390/ijms150713077
    The present study was conducted in order to assess the effect of various doses of acute gamma irradiation (0, 10, 15, and 20 Gy) on the improvement of bioactive compounds and their antioxidant properties of Curcuma alismatifolia var. Sweet pink. The high performance liquid chromatography (HPLC) and gas chromatography (GC) analysis uncovered that various types of phenolic, flavonoid compounds, and fatty acids gradually altered in response to radiation doses. On the other hand, antioxidant activities determined by 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), ferric reduction, antioxidant power (FRAP), and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay showed a higher irradiation level significantly increased the antioxidant properties. This study revealed an efficient effect of varying levels of gamma radiation, based on the pharmaceutical demand to enhance the accumulation and distribution of bioactive compounds such as phenolic and flavonoid compounds, fatty acids, as well as their antioxidant activities in the leaves of C. alismatifolia var. Sweet pink.
    Matched MeSH terms: Gamma Rays*
  2. Hafez EN, Awadallah FM, Ibrahim SA, Amin MM, El-Nawasera NZ
    Trop Biomed, 2020 Mar 01;37(1):89-102.
    PMID: 33612721
    Toxocara canis is a major parasite that infects many animals with high risk of human infections. This study aims at assessing the immunization with gamma radiationattenuated infective stage on rats challenged with non-irradiated dose. Level of vaccine protection was evaluated in liver and lung regarding parasitological, histopathological, biochemical and molecular parameters. Fifty rats were enrolled in three groups: group A (10 rats) as normal control; group B (20 rats) subdivided into subgroup B1 (infected control) and subgroup B2 infected then challenged after 14 days with the same dose of infection (challenged infected control); and group C (20 rats) subdivided into subgroup C1 vaccinated with a dose of 800 gray (Gy) gamma-radiated infective eggs (vaccine control) and subgroup C2 vaccinated then challenged on 14th day with same number of infective eggs (vaccinated-challenged). Tissues were stained with Haematoxylin and Eosin (H and E) for histopathological studies. Biochemical studies through detection of nitric oxide (NO) and Caspase-3 were conducted. Extent of DNA damage by Comet assay was assessed. Vaccinated-challenged subgroup revealed a marked reduction in larvae in tissues with mild associated histological changes. In addition there was accompanied reduction of NO, Casepase-3 level and DNA damage compared to the control infected group. It could be concluded that vaccination of rats with a dose of 800Gy gamma radiation-attenuated infective stage improves immune response to challenge infection and drastically reduces the morbidity currently seen.
    Matched MeSH terms: Gamma Rays
  3. Chowdhury MA, Jahan I, Karim N, Alam MK, Abdur Rahman M, Moniruzzaman M, et al.
    Biomed Res Int, 2014;2014:145159.
    PMID: 24711991 DOI: 10.1155/2014/145159
    In the present study, the residual pesticide levels were determined in eggplants (Solanum melongena) (n = 16), purchased from four different markets in Dhaka, Bangladesh. The carbamate and organophosphorus pesticide residual levels were determined by high performance liquid chromatography (HPLC), and the efficiency of gamma radiation on pesticide removal in three different types of vegetables was also studied. Many (50%) of the samples contained pesticides, and three samples had residual levels above the maximum residue levels determined by the World Health Organisation. Three carbamates (carbaryl, carbofuran, and pirimicarb) and six organophosphates (phenthoate, diazinon, parathion, dimethoate, phosphamidon, and pirimiphos-methyl) were detected in eggplant samples; the highest carbofuran level detected was 1.86 mg/kg, while phenthoate was detected at 0.311 mg/kg. Gamma radiation decreased pesticide levels proportionately with increasing radiation doses. Diazinon, chlorpyrifos, and phosphamidon were reduced by 40-48%, 35-43%, and 30-45%, respectively, when a radiation strength of 0.5 kGy was utilized. However, when the radiation dose was increased to 1.0 kGy, the levels of the pesticides were reduced to 85-90%, 80-91%, and 90-95%, respectively. In summary, our study revealed that pesticide residues are present at high amounts in vegetable samples and that gamma radiation at 1.0 kGy can remove 80-95% of some pesticides.
    Matched MeSH terms: Gamma Rays
  4. Wagiran, Husin, Supramaniam, Thiagu, Azali Mohamad, Abdul Aziz Mohamed, Faridah M. Idris
    MyJurnal
    Neutron aperture is one of the collimator components in a neutron radiography facility. The optimum design of neutron aperture is very importance in order to obtain largest L/D ratio with highest thermal neutron flux and low gamma-rays at the image plane. In this study, the optimization of neutron aperture parameters were done using Monte Carlo N-Particle Transport Code, version five (MCNP5). This code has a capability to simulate the neutron, photon, and electron or coupled of neutron/photon/electron transport, including the capability to calculate eigen values for critical system. The aperture parameters concerned in this study are the selection of best aperture material, aperture thickness, aperture position and aperture center hole diameter. In these simulations, vacuum beam port medium was applied.
    Matched MeSH terms: Gamma Rays
  5. Mohamad Awais, A. Syafiq Ramli, Abdul Aziz Mohamed, Megat Harun M.A., Azraf Azman, M. Rawi Md Zin, et al.
    MyJurnal
    This work main aim is to study the analysis of slow neutrons which include thermal and
    epithermal neutrons and also analysis on fast neutrons. The outcome from this work showed that
    the comparison result between fast and slow neutrons. The safety assessment at reactor TRIGA
    FUSFATI (RTF) is one of the main objectives of the work and there is a detailed discussion on it
    which helped in accomplishing the task. Gamma Rays produced in this experiment was high and in
    the experiment and it is realized that the shielding plays a vital role in the success of this
    experiment which prevents all the radiations. From the results of the experiment it is realized that
    these gamma rays are not suitable for the application of Boron Neutron Capture Therapy
    (BNCT). However, these radiations are suitable for the application of Neutron Radiography (NR).
    The study on this work will help in study of nuclear applications such as BNCT, NR, SANS etc.
    These applications are using in medical and nuclear fields. The electronic device used in the
    experiment to detect neutron is Neutron Spectrometer. The results from Neutron Spectrometer
    and TLDs are very similar which showed that the experiment is a success. Numerical results were
    compared with those available in literature for validation.
    Matched MeSH terms: Gamma Rays
  6. Garba NN, Ramli AT, Saleh MA, Sanusi SM, Gabdo HT
    Isotopes Environ Health Stud, 2016 Jun;52(3):214-8.
    PMID: 26540360 DOI: 10.1080/10256016.2016.1095189
    Measurements of the environmental terrestrial gamma radiation dose rate (TGRD) in each district of Kelantan state, Malaysia, were carried out using a portable hand-held radiation survey meter and global positioning system. The measurements were done based on geology and soil types of the area. The mean TGRD was found to be 209 nGy h(-1). Few areas of relatively enhanced activity were observed in Pasir Mas, Tanah Merah and Jeli districts, which have a mean TGRD between 300 and 500 nGy h(-1). An isodose map of the area was produced using ArcGIS software version 9.3.
    Matched MeSH terms: Gamma Rays*
  7. Khalil MI, Sulaiman SA, Alam N, Moniruzzaman M, Bai'e S, Man CN, et al.
    Molecules, 2012 Jan 11;17(1):674-87.
    PMID: 22237682 DOI: 10.3390/molecules17010674
    This study was conducted to evaluate the effects of evaporation, gamma irradiation and temperature on the total polyphenols, flavonoids and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities of Tualang honey samples (n = 14) following storage over three, six or twelve months. The mean polyphenol concentrations of the six gamma irradiated honey samples at three, six and twelve months, respectively, were 96.13%, 98.01% and 102.03% higher than the corresponding values of the eight non-gamma irradiated samples. Similarly, the mean values for flavonoids at three, six and twelve months were 111.52%, 114.81% and 110.04% higher, respectively, for the gamma irradiated samples. The mean values for DPPH radical-scavenging activities at three, six and twelve months were also 67.09%, 65.26% and 44.65% higher, respectively, for the gamma irradiated samples. These data indicate that all gamma irradiated honey samples had higher antioxidant potential following gamma irradiation, while evaporation and temperature had minor effects on antioxidant potential.
    Matched MeSH terms: Gamma Rays*
  8. Mohd Adzahan, N., Mat Hashim, D., Muhammad, K., Abdul Rahman, R., Ghazali, Z., Hashim, K.
    MyJurnal
    Changes to the physicochemical properties of wheat, sago and tapioca starches subjected to gamma ray, electron beam and microwave irradiations and the conditions that lead to wheat starch having leaching behaviour similar to sago or tapioca starch were studied. The properties were characterised through swelling and leaching behaviours of the starch granules and retrogradation following pasting. The leaching of wheat starch increased tremendously and resulted in amylose to amylopectin ratios in the leachate similar to that of native sago and tapioca starches. This observation is significant as wheat starch is known to have a leachate composition of mostly amylose. This opens up the possibility of utilising wheat starch in snacks where tapioca and sago starch are commonly used. It was observed that the required conditions for such changes were exposure to microwave for 8 and 10 minutes, electron beam at 5 and 10 kGy and gamma ray at 5 kGy.
    Matched MeSH terms: Gamma Rays
  9. Ab Hamid SS, Zahari NK, Yusof N, Hassan A
    Cell Tissue Bank, 2014 Mar;15(1):15-24.
    PMID: 23187886 DOI: 10.1007/s10561-012-9353-x
    Human amniotic membrane that has been processed and sterilised by gamma irradiation is widely used as a biological dressing in surgical applications. The morphological structure of human amniotic membrane was studied under scanning electron microscopy (SEM) to assess effects of gamma radiation on human amniotic membrane following different preservation methods. The amniotic membrane was preserved by either air drying or submerged in glycerol before gamma irradiated at 15, 25 and 35 kGy. Fresh human amniotic membrane, neither preserved nor irradiated was used as the control. The surface morphology of glycerol preserved amnion was found comparable to the fresh amniotic membrane. The cells of the glycerol preserved was beautifully arranged, homogonous in size and tended to round up. The cell structure in the air dried preserved amnion seemed to be flattened and dehydrated. The effects of dehydration on intercellular channels and the microvilli on the cell surface were clearly seen at higher magnifications (10,000×). SEM revealed that the changes of the cell morphology of the glycerol preserved amnion were visible at 35 kGy while the air dried already changed at 25 kGy. Glycerol preservation method is recommended for human amniotic membrane as the cell morphological structure is maintained and radiation doses lower than 25 kGy for sterilization did not affect the appearance of the preserved amnion.
    Matched MeSH terms: Gamma Rays
  10. Hasan N, Sham NFR, Karim MKA, Fuad SBSA, Hasani NAH, Omar E, et al.
    Sci Rep, 2021 Jul 15;11(1):14559.
    PMID: 34267293 DOI: 10.1038/s41598-021-93964-5
    We presented a development of a custom lead shield and mouse strainer for targeted irradiation from the gamma-cell chamber. This study was divided into two parts i.e., to (i) fabricate the shield and strainer from a lead (Pb) and (ii) optimize the irradiation to the mice-bearing tumour model with 2 and 8 Gy absorbed doses. The lead shielding was fabricated into a cuboid shape with a canal on the top and a hole on the vertical side for the beam path. Respective deliveries doses of 28 and 75 Gy from gamma-cell were used to achieve 2 and 8 Gy absorbed doses at the tumour sites.
    Matched MeSH terms: Gamma Rays
  11. Yusof MFM, Hamid PNKA, Tajuddin AA, Hashim R, Bauk S, Isa NM, et al.
    Radiol Phys Technol, 2017 Sep;10(3):331-339.
    PMID: 28718054 DOI: 10.1007/s12194-017-0408-3
    The aim of this study was to determine the suitability of tannin-added Rhizophora spp. particleboards as phantom materials in the application of low- and high-energy photons. The tannin-added Rhizophora spp. particleboards and density plug phantoms were created with a target density of 1.0 g/cm3. The elemental composition and effective atomic number of the particleboards were measured using energy dispersive X-ray analysis. The mass attenuation coefficient of the particleboards for low-energy photons were measured using the attenuation of X-ray fluorescence. The mass attenuation coefficients of high-energy photons were measured using the attenuation of 137Cs and 60Co gamma energies. The results were compared to the calculated value of water using XCOM calculations. The results showed that the effective atomic number and mass attenuation coefficients of tannin-added Rhizophora spp. particleboards were similar to those of water, indicating the suitability of tannin-added Rhizophora spp. particleboards as phantom materials for low- and high-energy photons.
    Matched MeSH terms: Gamma Rays*
  12. Md Fakarudin Ab Rahman, M. Iqbal Saripan, Nor Pa’iza Mohamad Hasan, Ismail Mustapha
    MyJurnal
    The total mass attenuation coefficients (μ/ρ) of stainless steel (SS316L) and carbon steel (A516) that are widely used as petrochemical plant components, such as distillation column, heat exchanger, boiler and storage tank were measured at 662, 1073 and 1332 keV of photon energies. Measurements of radiation intensity for various thicknesses of steel were made by using transmission method. The γ-ray intensity were counted by using a Gamma spectrometer that contains a Hyper-pure Germanium (HPGe) detector connected with Multi Channel Analyzer (MCA). The effective numbers of atomic (Zeff) and electron (Neff) obtained experimentally were compared by those obtained through theoretical calculation. Both experimental and calculated values of Zeff and Neff were in good agreement.
    Matched MeSH terms: Gamma Rays
  13. Husnain AU, Mokhtar N, Mohamed Shah NB, Dahari MB, Azmi AA, Iwahashi M
    PLoS One, 2024;19(2):e0296969.
    PMID: 38394180 DOI: 10.1371/journal.pone.0296969
    There are three primary objectives of this work; first: to establish a gas concentration map; second: to estimate the point of emission of the gas; and third: to generate a path from any location to the point of emission for UAVs or UGVs. A mountable array of MOX sensors was developed so that the angles and distances among the sensors, alongside sensors data, were utilized to identify the influx of gas plumes. Gas dispersion experiments under indoor conditions were conducted to train machine learning algorithms to collect data at numerous locations and angles. Taguchi's orthogonal arrays for experiment design were used to identify the gas dispersion locations. For the second objective, the data collected after pre-processing was used to train an off-policy, model-free reinforcement learning agent with a Q-learning policy. After finishing the training from the training data set, Q-learning produces a table called the Q-table. The Q-table contains state-action pairs that generate an autonomous path from any point to the source from the testing dataset. The entire process is carried out in an obstacle-free environment, and the whole scheme is designed to be conducted in three modes: search, track, and localize. The hyperparameter combinations of the RL agent were evaluated through trial-and-error technique and it was found that ε = 0.9, γ = 0.9 and α = 0.9 was the fastest path generating combination that took 1258.88 seconds for training and 6.2 milliseconds for path generation. Out of 31 unseen scenarios, the trained RL agent generated successful paths for all the 31 scenarios, however, the UAV was able to reach successfully on the gas source in 23 scenarios, producing a success rate of 74.19%. The results paved the way for using reinforcement learning techniques to be used as autonomous path generation of unmanned systems alongside the need to explore and improve the accuracy of the reported results as future works.
    Matched MeSH terms: Gamma Rays
  14. Nurul Fadzlin Hasbullah, Nuurul Iffah Che Omar, Nahrul Khair Alang Md Rashid, Jaafar Abdullah
    MyJurnal
    Nuclear technology has found a great need for use in medicine, industry, and research. Smoke
    detectors in our homes, medical treatments and new varieties of plants by irradiating its seeds are just a few examples of the benefits of nuclear technology. Portable neutron source such as Californium-252, available at Industrial Technology Division (BTI/PAT), Malaysian Nuclear Agency, has a 2.645 year half-life. However, 252 Cf is known to emit gamma radiation from the source. Thus, this chamber aims to provide a proper gamma shielding for samples to distinguish the use of mixed neutron with gamma-rays or pure neutron radiation. The chamber is compatible to be used with other portable neutron sources such as 241 Am-Be as well as the reactor TRIGA PUSPATI for higher neutron dose. This chamber was designed through a collaborative effort of Kulliyyah Engineering, IIUM with the Bahagian Teknologi Industri (BTI) team, Agency Nuklear Malaysia.
    Matched MeSH terms: Gamma Rays
  15. Selambakkannu, Sarala, Bakar, Khomsaton Abu, Ming, Ting Teo, Jamaliah Sharif
    MyJurnal
    In this studies gamma and electron beam irradiation was used to treat textile waste water. Comparisons between both types of irradiation in terms of effectiveness to degrade the pollutants present in textile waste water were done. Prior to irradiation, the raw wastewater was diluted using distilled water to a target concentration of COD 400 mg/l. The sample was irradiated at selected doses between the ranges of 10 kGy to 100 kGy. The results showed that irradiation has significantly contributed in the reduction of the highly colored refractory organic pollutants. The COD removal at the lowest dose, 10 kGy was reduced to 390 mg/l for gamma and 400 mg/l for electron beam. Meanwhile, at the highest dose, 100 kGy, the COD was reduced to 125 mg/l for gamma and 144 mg/l for electron beam. The degree of removal is influenced by the dose introduced during the treatment process. As the dose increased, the higher the removal of organic pollutant was recorded. However, gamma irradiation is more effective although the differences are not significant between gamma and electron beam irradiation. On the other hand, other properties of the wastewater such as pH, turbidity, suspended solid, BOD and color also shows a gradual decrease as the dose increases for both types of irradiation.
    Matched MeSH terms: Gamma Rays
  16. Chiew, Miao Si, Lai, Kok Song, Sobri Hussein, Janna Ong Abdullah
    MyJurnal
    Stevia rebaudiana Bertoni in the Asteraceae family is commercially valuable and cultivated throughout the world due to the great demand for its steviol glycosides (SGs) contents particularly rebaudioside A. Previous studies confirmed that maximal content of SGs in stevia was achieved at or just before flowering, and delayed flowering with long days provide longer duration for steviol glycosides accumulation. However, there is no suitable stevia variety to be cultivated in Malaysia due to her short day length. Mutation induction, including gamma irradiation, had been shown to be useful for generating genetic variations as well as developing new plant varieties from which desired mutants were successfully selected. The use of mutagens, both physical and chemical, has helped in creating mutants that expressed the selected desirable traits. This paper presents some selected essential data available in extant scientific studies on stevia with the focus on application of gamma irradiation on stevia. Both established achievements and recent publications of gamma radiation on stevia were reviewed. Emphasis is on the exceptional potential of stevia through induced mutation approach especially by using gamma rays.
    Matched MeSH terms: Gamma Rays
  17. Saidu A, Wagiran H, Saeed MA, Alajerami YSM, Kadir ABA
    Appl Radiat Isot, 2016 Dec;118:375-381.
    PMID: 27894049 DOI: 10.1016/j.apradiso.2016.10.005
    The effect of sodium as a co-dopant on the thermoluminescence (TL) properties of copper-doped zinc lithium borate (ZLB: Cu) subjected to Co-60 gamma radiation is reported in this study. TL intensity is enhanced with the introduction of sodium in ZLB: Cu. The obtained glow curve is simple with a single peak. The annealing procedure and the best heating rate for the proposed thermoluminescent dosimeter (TLD) are established, and the phosphor is reusable. The TL response within the dose range of 0.5-1000Gy is investigated. The results show that the thermal fading behaviour is improved significantly.
    Matched MeSH terms: Gamma Rays
  18. Dolah MT, Samat SB, Kadni T
    Malays J Med Sci, 2000 Jan;7(1):47-53.
    PMID: 22844215
    Absorbed dose to water was measured with ionisation chambers NE 2561 (#267), NE 2581 (#334), NE 2571 (#1028), using the IAEA standard water phantom. The ionisation chamber was inserted in the water phantom at a reference depth dependent on the type of the radiation quality used. Three radiation qualities were used namely 1.25 MeV gamma ray, 6 MV x-rays and 10 MV x-rays. The values of the absorbed dose to water were determined by the N(K)- and N(X)- based methods, i.e with the use of IAEA, HPA, NACP, AAPM, NCRP and ICRU protocols. The aim of this study was to make an intercomparison of the results, by taking the IAEA protocol as a standard. The largest deviation contributed by any of these protocols was recorded for each quality. It was found that AAPM, NCRP and ICRU protocols contributed 0.94% for 1.25 MeV gamma ray, NACP contributed 2.12% for the 6 MV x-rays, and NACP contributed 2.35% for 10 MV x-rays. Since the acceptable limit of deviation set by the IAEA for this absorbed dose work is ± 3%, it is clear that the overall deviations obtained were all satisfactory.
    Matched MeSH terms: Gamma Rays
  19. Abedini A, Daud AR, Abdul Hamid MA, Kamil Othman N
    PLoS One, 2014;9(3):e90055.
    PMID: 24608715 DOI: 10.1371/journal.pone.0090055
    Colloidal Fe3O4 nanoparticles were synthesized using a gamma-radiolysis method in an aqueous solution containing iron chloride in presence of polyvinyl alcohol and isopropanol as colloidal stabilizer and hydroxyl radical scavenger, respectively. Gamma irradiation was carried out in a 60Co gamma source chamber at different absorbed doses. Increasing the radiation dose above a certain critical dose (100 kGy) leads to particle agglomeration enhancement, and this can influence the structure and crystallinity, and consequently the magnetic properties of the resultant particles. The optimal condition for formation of Fe3O4 nanoparticles with a uniform and narrow size distribution occurred at a dose of 100 kGy, as confirmed by X-ray diffractometry and transmission electron microscopy. A vibrating sample magnetometry study showed that, when radiation dose increased, the saturation and remanence magnetization decreased, whereas the coercivity and the remanence ratio increased. This magnetic behavior results from variations in crystallinity, surface effects, and particle size effects, which are all dependent on the radiation dose. In addition, Fourier transform infrared spectroscopy was performed to investigate the nature of the bonds formed between the polymer chains and the metal surface at different radiation doses.
    Matched MeSH terms: Gamma Rays
  20. Garba NN, Abdulkadir M, Nasiru R, Saleh MA, Bello S, Khandaker MU, et al.
    Isotopes Environ Health Stud, 2023 Mar;59(1):112-125.
    PMID: 36735938 DOI: 10.1080/10256016.2023.2172001
    Terrestrial gamma radiation dose (TGRD) rates were measured in situ from different locations in Katsina State, Nigeria, using a portable radiation survey metre based on geological formations and soil types. The measured TGRD rates ranged from 45 to 271 nGyh-1 with an average value of 116 ± 1 nGyh-1. Geological formation (silicified sheared rock) and soil type (lithosols and ferruginous crusts and ferruginous tropical soils) appeared to have the highest mean TGRD values of 163 and 134 nGyh-1 with sandstone geological formation and alluvial and hydromorphic soils having the lowest TGRD with values of 80 and 61 nGyh-1, respectively. One way ANOVA results shows that the tested null hypothesis was rejected. Thus, indicating that there exists a strong relationship between the various geological formations, soil types with the measured TGRD values based on the alternate hypothesis. Human health hazard indices like annual effective dose equivalent (AEDE), lifetime outdoor annual equivalent dose, and relative excess lifetime outdoor cancer risk associated with the mean TGRD of the study area were also calculated and found to be 0.711, 9.955 mSv, and 5.79 × 10-4, respectively. These values were higher than the world average values but favourable compared with the safety limits recommended by ICRP.
    Matched MeSH terms: Gamma Rays
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