Doses Of Gamma Radiation Research Articles

Structural and Electrochemical Evolution of Water Hyacinth-Derived Activated Carbon with Gamma Pretreatment for Supercapacitor Applications.

This study introduces a gamma pretreatment of water hyacinth powder for activated carbon (AC) production with improved electrochemical properties for supercapacitor applications. The structural and morphological changes of post-irradiation were meticulously analyzed using scanning electron microscopy (SEM), Raman spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS). The pretreatment significantly modifies the pore structure and reduces the particle size of the resulting activated carbon (WHAC). Nitrogen adsorption-desorption isotherms indicated a substantial increase in micropore volume with escalating doses of gamma irradiation. Electrochemically, the activated carbon produced from pretreated WH at 100 kGy exhibited a marked increase in specific capacitance, reaching 257.82 F g-1, a notable improvement over the 95.35 F g-1 of its untreated counterpart, while maintaining 99.40% capacitance after 7000 cycles. These findings suggest that gamma-pretreated biomasses are promising precursors for fabricating high-performance supercapacitor electrodes, offering a viable and environmentally friendly alternative for energy storage technology development.

Investigation of structural and TL kinetic parameters of smartphone screen protector glasses for applications in retrospective dosimetry

The study evaluated the structural and thermoluminescence (TL) kinetic parameters of smartphone screen protector glasses in order to use them for post-accident dose reconstruction from unplanned nuclear events. The fact that most individuals use mobile phones in working environments including nuclear power plant sites, served as the impetus for the study. The TL glow curves indicate the physical properties of the defects involved in the luminescence process; therefore, they have been analyzed to study the TL kinetic parameters by employing peak shape, initial rise and glow curve deconvolution method within the dose ranges from 2 to 50 Gy. The geometric factor (μg) ranges between 0.46 and 0.56, suggesting that Chen's general-order method can be used to compute the kinetic parameters, including activation energy (E), frequency factor (s) and trap lifetime (τ). The examined trapping parameters (E = 0.33–0.57 eV, s = 5.22E+03–8.65E+06 s−1 for peak shape and E = 0.36–0.96 eV, s = 2.90E+04–1.88E+11 s−1 for initial rise methods) suggest promise for TL dosimetry applications. Additionally, the observed lifetime (τ = 4.88E+5 s) implies the feasibility of dose reconstruction even several days after an accident, making it suitable for retrospective dosimetry. Micro-Raman spectroscopy revealed a clear correlation between increasing gamma radiation dose and microstructural damage. The analysis of intensity ratio (ID/ISi) for other components to silica, along with the area of deconvoluted micro-Raman spectra in high-frequency regions, indicated dose-dependent structural modifications and internal defect annealing. Further confirmation of structural alterations within the studied dose range was obtained through the analysis of crystallite size (Lc), dislocation density (δ), lattice strain (ɛ) and FWHM (Full Width at Half Maximum) from XRD (X-ray diffraction) patterns. These findings collectively suggest the potential of smartphone screen protector glass as a viable material for emergency dosimetry applications.

Assessment of Naturally Occurring Radionuclide in Soil Samples from Kutayi Mining Sites in Muya Local Government Area, Niger State, Nigeria

This work examines the Kutayi mining sites with a view of assessing the activity concentration and effective dose rate of NORM (i.e. 40K, 232Th and 226Ra) in these site absorbed in 8 soil samples collected from different areas within the Kutayi mining sites, A γ-ray spectrometry NaI (Tl) at CERT. ABU Zaria, was used to carry out the analysis of the soil samples. The result shows that, activity concentration for 40K ranged from 428.9269 to 93.6236 BqKg-1; for 226Ra it ranged from 50.1738 to 13.7891 BqKg-1 and for 232Th the ranged is from 52.1095 to 18.7457 Bq.Kg-1, the absorbed dose for 40K ranged from 17.8863 to 3.9041 ŋGy.h-1, for 226Ra the range is from 23.1803 to 3.1614 ŋGy.h-1 and for 232Th range from 31.47419 to 11.3224 ŋGy.h-1. The total mean absorbed dose rate is 42.5341 ŋGy.h-1 and the annual effective dose range from 0.0355 mSvy-1 (i.e. 36 – 76 μSv.y-1), with an mean annual effective dose of 0.0522 mSv.y-1 (i.e. 52.2 μSv.y-1, Also the mean Radium Equivalents (Raeq) obtained ranged from 64.0280 BqKg-1 (KT6) to 135.3245 BqKg-1 (KT8). This results show that, the Raeq is 370 BqKg-1 which is the requirement for soil to be used for dwellings; hence the soil from this site is suitable use for buildings. The mean Hext ranged from 0.1730 Bqkg-1 (KT6) to 0.3438 Bqkg-1 (KT8). The maximum allowed value of (Hext = 1) corresponds to the upper limit of Raeq (370 BqKg-1) in order to limit the external gamma radiation dose from the soil to 1.5 mGy y-1, i.e. index should Hext = 1. All these values for Iα are below the maximum permissible value of Iα= 1 which corresponds to 200 Bq.Kg-1. Hence no radiological hazard is envisaged to dwellers of the study areas and the miners working on those sites.

Cellulose fiber derived from sugarcane bagasse and polyethylene glycol/acrylic acid/ branched polyethylenimine-based hydrogel composite prepared by gamma irradiation: A platform for mercury (II) ions adsorption

In this study, cellulose was successfully purified from sugarcane bagasse by alkali treatment and bleaching process. Then, 2-10 wt% of purified cellulose was added into polyethylene glycol and acrylic acid-based hydrogel composite. 25 kGy of gamma irradiation dose was employed to form the gel. With the presence of various cellulose contents, no significant change of functional group was therefore observed. The hydrogel composite was thermally resisted up to 250°C. The microstructure of composite exhibited as an interconnected porosity throughout hydrogel network. Cellulose was located inside hydrogel composite. The gel fraction and porosity for all of composites were reported to be 92-97% and 73-81%, respectively. The swelling behavior was very rapid within initial stage (5 hours) and then, it presented as a plateau region. The presence of purified cellulose significantly offered high dimensional stability. After that, in order to enhance the ability for Hg2+ adsorption, bPEI was coated onto the surface of hydrogel composite. FTIR was employed to evaluate the presence of N-H stretching. At the neutral pH, it defined as an optimal region for adsorption. The efficiency and capacity for Hg2+ adsorption were reported to be 55.17% and 82.94 mg/g in 24 hours, respectively. This was related to the pseudo-second-order kinetic model due to R2 of 0.9941 indicating the chemical adsorption process. Furthermore, EDX analysis confirmed that the existence of Hg was presented onto hydrogel composite surface. It was remarkably noted that purified cellulose from sugarcane bagasse was successfully inserted into hydrogel composite by gamma irradiation technique. It provided a great promise as a platform for mercury ion adsorption.

Poziomy zewnętrznych dawek promieniowania gamma w wybranych miejscach w Rumunii, Mołdawii i Grecji

The study presents a synthesis of results obtained in the frame of international cross-border projects, implemented in partnership, for gamma radiation dose rates measured in outdoor environments in various sites in Romania, Moldova, Greece, including urban, rural, touristic and protection areas. The selected sites (n=41) are found in the Eastern Carpathians Mountains, Lower Danube basin, Danube Delta, Lower Prut River Reserve, Dniester River, as well as Black Sea and Northern Aegean Sea basins. The data recorded for targeted spots using portable dosimeters highlight an hourly and daily variation of the outdoor gamma dose rate and the specificity of the geological background and terrain utilization. The mean values of outdoor gamma radiation dose rate, calculated for 50 measurements per each site, are ranging between 71 nGy/h (Vama Veche, Constanta County, Black Sea coast, Romania) and 394 nGy/h (Nea Peramos, Ammolofoi beach, Northern Aegean Sea, Greece), with a minimum of 41 nGy/h in Vama Veche and a maximum of 489 nGy/h in Ammolofoi beach. A comparison is made with legislated values and other world places. The measurements performed at water surface during boat expeditions (n=21) on Danube River and Danube Delta lakes and channels point out lower values of dose rate, due to the weak influence of gamma rays’ emission from bottom sediments. The data of the dose rate temporal variations will be used for the target regions as a base in further investigations and preparation of maps of gamma dose rates (terrestrial and cosmic), and calculation of the health risk for inhabitants and tourists.

Characterization of natural organic matter in Wyoming-type bentonites irradiated at varied moisture levels

Wyoming-type bentonite clay (MX-80; Wyoming, USA) will be used in a deep geological repository (DGR) for the long-term storage of used nuclear fuel in Canada. The natural organic matter (NOM) found in bentonite may serve as a microbial nutrient source and potentially compromise the performance of the used fuel containers. Previous investigations indicate that NOM is present in low concentrations in MX-80 and has undergone extensive diagenetic alteration, though limited knowledge is available regarding NOM chemistry under simulated DGR conditions. Of particular concern is the possibility for gamma-radiation to alter NOM dissolution and reactivity due to the presence of reactive species generated by water radiolysis in Wyoming-type bentonites. In this study, NOM chemistry was investigated using complementary molecular-level techniques following exposure to a total gamma-radiation dose of 100 kGy (1.08 kGy/h for 93 h) at varied moisture levels (20%, 40%, 60% and 80%) and room temperature. Treated samples exhibited relatively low total organic carbon concentrations (0.074–0.232%), with no evidence of any major changes in total, organic, and inorganic carbon concentrations. Solid-state 13C NMR spectroscopy detected no changes in solid-phase NOM chemistry after irradiation. Solubilization of NOM increased significantly with radiation exposure at 80% moisture, suggesting higher levels of water saturation may enhance dissolved organic matter (DOM) production. Solution-state 1H nuclear magnetic resonance (NMR), and UV–Vis analyses did not identify any significant differences in DOM composition. More sensitive, targeted compound analysis revealed significant decreases in total n-alkanol concentration at lower moisture content levels (20% and 40%). Several individual compound concentrations also differed significantly at the nanogram-level, including n-octacosanol and several n-alkanoic acids at elevated moisture levels (60% and 80%). These findings suggest the majority of NOM in MX-80 remains chemically stable under the anticipated initial conditions of the proposed DGR.

Combined Effect of Gamma Radiation and Heavy Metals on Some Living Organisms.

The purpose of this study was to systematise scientific publications on the combined effect of gamma radiation and heavy metals on living organisms. For this purpose, the method of analysis was applied, by means of which scientific papers in PubMed, Google Scholar, and other related databases were analysed for compliance with the inclusion criteria, where the objects of research were toxic effects of radiation and heavy metals on cells and adaptation processes. The results revealed that the study of the problem was carried out on organisms such as microalgae, fungi, weed and agricultural plants, fish, laboratory rats, and human cell cultures. In most studies, an antagonistic effect between low doses of gamma radiation and heavy metal salts was reported, which was manifested by a reduction in the cytotoxicity of isolated exposure to each agent separately. However, there are studies showing additive effects, especially in heavy metals. At the molecular level, heavy metal accumulation in combination with low doses of radiation (typically defined as less than 0.1Gy or sievert) induces the expression of metallothionein proteins, which can bind free radicals. At the metabolic level, this is manifested by a decrease in lipid peroxidation products, activation of antioxidant enzymes, and a decrease in apoptosis. The study proved both a direct relationship between zinc and cadmium accumulation in cells and inhibition of caspases and an indirect one, by maintaining mitochondrial membrane integrity through metallothionein.

Nano-modifications of edible materials using ionizing radiation for potential application in active food safety

Active food packaging films from Carboxy methyl cellulose and starch (CMC-g-Starch) reinforced with Magnesium-oxide (MgO) NPs are created and characterized. The effect of different particle sizes, MgO NPs concentrations and different gamma irradiation doses on the preparation of (CMC-g-Starch-MgO) edible nanocomposite films were investigated to determine their properties. Several analytical methods, such as swelling behavior, FT-IR, TEM, TGA, and mechanical characteristics, are represented to investigate different characteristics of the prepared (CMC-g-Starch-MgO) edible nanocomposite films. Also, the prepared (CMC-g-Starch-MgO) edible nanocomposite films and their coating were subjected to the fresh Peaches fruits. Their effect on the Peach fruits' lifespan was evaluated. The anti-microbial property of the edible (CMC-g-Starch-MgO) nanocomposite films of gram (+ve) and gram (–ve) bacteria was reported. Results represented the thermal and mechanical characteristics of (CMC-g-Starch-MgO) edible nanocomposite films, which were enhanced by γ irradiation. Also, the irradiated (CMC-g-Starch-MgO) edible nanocomposite films and their coating extend the lifespan of Peaches fruits and exhibit resistance to pathogenic microorganisms. In conclusion, (CMC-g-Starch-MgO) edible nanocomposite films fulfilled the required behaviors for the application in the nanofood packaging era.

Proteomic analysis of plasma at the preterminal stage of rhesus nonhuman primates exposed to a lethal total-body dose of gamma-radiation

The identification and validation of radiation biomarkers is critical for assessing the radiation dose received in exposed individuals and for developing radiation medical countermeasures that can be used to treat acute radiation syndrome (ARS). Additionally, a fundamental understanding of the effects of radiation injury could further aid in the identification and development of therapeutic targets for mitigating radiation damage. In this study, blood samples were collected from fourteen male nonhuman primates (NHPs) that were exposed to 7.2 Gy ionizing radiation at various time points (seven days prior to irradiation; 1, 13, and 25 days post-irradiation; and immediately prior to the euthanasia of moribund (preterminal) animals). Plasma was isolated from these samples and was analyzed using a liquid chromatography tandem mass spectrometry approach in an effort to determine the effects of radiation on plasma proteomic profiles. The primary objective was to determine if the radiation-induced expression of specific proteins could serve as an early predictor for health decline leading to a preterminal phenotype. Our results suggest that radiation induced a complex temporal response in which some features exhibit upregulation while others trend downward. These statistically significantly altered features varied from pre-irradiation levels by as much as tenfold. Specifically, we found the expression of integrin alpha and thrombospondin correlated in peripheral blood with the preterminal stage. The differential expression of these proteins implicates dysregulation of biological processes such as hemostasis, inflammation, and immune response that could be leveraged for mitigating radiation-induced adverse effects.

Synthesis and Characterization of Low Molecular Weight Irradiated Chitosan in Various Water Levels and Gamma-Ray Doses

Chitosan is a biopolymer derived from marine animal shell waste that exhibits numerous pharmacological activities. However, its high molecular weight limits the application in various fields due to its low solubility. Therefore, this study aims to synthesize low molecular weight chitosan using varying water content and doses of gamma irradiation. To initiate chitosan degradation, H2O (5 and 10 mL) was added, followed by gamma ray irradiation at doses of 5 and 10 kGy. The Molecular Weight (MW) of degraded chitosan was determined using Gel Permeation Chromatography (GPC), while Fourier Transform Infrared Spectroscopy (FTIR) was used to characterize the functional groups and degree of deacetylation of chitosan. The study found that the molecular weight of irradiated chitosan decreased as the irradiation dose and H2O addition increased. The addition of 10 mL of water and gamma irradiation at a dose of 10 kGy has been found to reduce the molecular weight of chitosan to 118 kDa, with a high deacetylation degree of 86.78%. The FTIR analysis showed no significant changes in the functional groups, indicating that gamma irradiation did not affect the structure of chitosan.

Effect of Gamma Irradiation Dose on the Interface and Tribological Properties of Acrylonitrile–Butadiene–Styrene

Effect of Gamma Irradiation Dose on the Interface and Tribological Properties of Acrylonitrile–Butadiene–Styrene

Multi-variate multi-objective optimization of production conditions for electro-spun skin scaffold using RSM and investigation of gamma irradiation effects on the properties of the optimized sample

Developing electro-spun scaffolds with ideal mechanical properties for skin purposes can profit from using the Response Surface Methodology technique to define and optimize the outcome quality and required sterilization for use in vivo. This study investigated the effects of four main independent electrospinning variables for polycaprolactone nanofibers scaffold using multi-variable and multi-objective optimization. It was done to determine significant parameters on responses and find optimal conditions to reach the preferred properties. Young's modulus, elongation-at-break, and tensile strength were the responses. After obtaining appropriate models, the impact share of variables on the responses was determined using Sobol sensitivity analysis. The results showed that flow rate is the most significant parameter of elastic modulus and tensile strength responses, with 76.45 % and 41.27 % impact shares, respectively. The polymer concentration is the following significant parameter on elongation at break, tensile strength and, Young's modulus responses with 64.35 %, 39.485 and, 14.28 % impact share, respectively. Based on the optimized results, a skin scaffold with desired mechanical properties was achieved (under solution concentration of 10 % w/v, flow rate of 2 mL/h, nuzzle-collector distance of 15 cm, and applied voltage of 20 kV). Then it was sterilized with gamma radiation of various doses (25, 40, and 55 kGy) to use in vivo. The SEM analysis indicated no significant change in fibrous morphology due to gamma irradiation at any dosage. FTIR analysis demonstrated the breakup of ester bonds due to gamma irradiation. For samples irradiated by 25 kGy, the crystallinity percentage decreased and chains crosslinking without losing the mechanical stability was dominant. The studies demonstrated that 25 kGy of gamma irradiation could improve the mechanical properties of the optimized PCL skin scaffold, which is very promising for wound healing.

Optimizing Tomato Bareto (Lycopersicum esculentum MILL) Varieties Growth and Production Using Gamma Ray Radiation Technology

Research is currently being conducted on the impact of gamma-ray radiation on the growth and productivity of the Bareto tomato variety (Lycopersicum esculentum Mill), renowned for its sizable, vibrant red fruits and unique sweet flavor. This study aims to establish the most effective dosage of gamma radiation for promoting seed germination, enhancing plant height, and increasing leaf count. The experiment utilized a non-factorial, completely randomized design involving four treatments (0 Gy, 100 Gy, 200 Gy, and 300 Gy) with five replications. The findings indicated that doses of 200 Gy and 300 Gy led to a significant enhancement in seed germination, demonstrating a consistent improvement in the viability of Bareto tomato seeds. However, the height of the plants displayed a negligible rise at radiation doses of 200 Gy and 300 Gy compared to the control and 100 Gy, suggesting that the impact of radiation dosage on plant height development may not be significant. In contrast, there was a notable increase in the quantity of leaves at dosages of 200 Gy and 300 Gy during observations at 2 and 3 weeks after planting (WAP). This suggests that elevated levels of gamma radiation had a favorable impact on leaf growth

Modification of WS2 thin film properties using high dose gamma irradiation

The tunability of the transition metal dichalcogenide properties has gained attention from numerous researchers due to their wide application in various fields including quantum technology. In the present work, WS2 has been deposited on fluorine doped tin oxide substrate and its properties have been studied systematically. These samples were irradiated using gamma radiation for various doses, and the effect on structural, morphological, optical and electrical properties has been reported. The crystallinity of the material is observed to be decreased, and the results are well supported by x-ray diffraction, Raman spectroscopy techniques. The increase in grain boundaries has been supported by the agglomeration observed in the scanning electron microscopy micrographs. The XPS results of WS2 after gamma irradiation show evolution of oxygen, carbon, C=O, W–O and SO4 −2 peaks, confirming the addition of impurities and formation of point defect. The gamma irradiation creates point defects, and their density increases considerably with increasing gamma dosage. These defects crucially altered the structural, optical and electrical properties of the material. The reduction in the optical band gap with increased gamma irradiation is evident from the absorption spectra and respective Tauc plots. The I–V graphs show a 1000-fold increase in the saturation current after 100 kGy gamma irradiation dose. This work has explored the gamma irradiation effect on the WS2 and suggests substantial modification in the material and enhancement in electrical properties.

Gamma-irradiation-induced tailoring of physical, electrical, optical, and mechanical properties of PVC/PANI/TiO2 nanocomposites for different applications

Gamma irradiation exhibits a complex influence on the properties of PVC/PANI/TiO2 nanocomposite films. XRD analysis reveals a non-monotonic response in crystallinity, with an initial increase at lower doses due to crosslinking followed by a decrease at higher doses attributed to polymer chain scission. Mechanical properties exhibit an improvement in tensile strength and Young's modulus at moderate doses (up to 100 kGy) due to crosslinking. However, excessive irradiation (>100 kGy) induces chain degradation, causing a decrease in both tensile strength and elongation at break. Similar dose-dependent behavior is observed in thermal properties, with moderate doses improving thermal stability and melting temperature before a decline at higher doses due to chain degradation. Gamma irradiation significantly affects AC conductivity, suggesting potential changes in structure, charge carrier density, and conduction mechanisms. While the core chemical structure remains largely unaffected, FTIR and UV–Vis spectroscopy analyses indicate alterations in the degree of crosslinking and optical properties, warranting further investigation. Refractive index increases with irradiation due to enhanced density and changes in polarizability. This study highlights the importance of tailoring the gamma irradiation dose to achieve desired properties in PVC/PANI/TiO2 nanocomposite films for various applications.

Screening the optimal dose of gamma radiation for Tuta absoluta sterility: paving the way for sterile insect technique programs

Screening the optimal dose of gamma radiation for Tuta absoluta sterility: paving the way for sterile insect technique programs

Irradiation-assisted synthesis of smart hydrogels based on nanomagnetic semi-interpenetrating p(HEMA)/PVP networks for the cleaning of cultural heritage artifacts

Preservation of our cultural and historical heritage as a testimony to our shared past is a responsibility that demands significant attention. One of the most critical and delicate aspects of conserving such treasures is cleaning them safely and effectively. Chemical hydrogels specifically designed for cleaning cultural heritage artifacts allow for the containment and controlled release of water. Based on a generic approach, a smart nanomagnetic hydrogel was developed using a semi-interpenetrating polymer network (semi-IPN) of polyhydroxyethyl methacrylate (p(HEMA)) and polyvinyl pyrrolidone (PVP). Gamma irradiation was employed to perform simultaneous in-situ polymerization, crosslinking, and also immobilization of iron oxide magnetic nanoparticles (MNPs). The chemical and structural characteristics of the nanomagnetic hydrogel were investigated using gel content, equilibrium water content, field-emission scanning electron microscopy, magnetic properties, compressive strength, dehydration kinetics, and adhesion tests. The optimal formula for smart hydrogel was a ratio of monomer to polymer 50:50, a water content of 60 wt.%, a gamma radiation dose of 20 kGy, and 3 wt.% of MNP. Two cotton canvas case studies demonstrate the versatility and effectiveness of the selected hydrogel in removing dirt and confining the water-based cleaning system. It was found that no color leaching occurred during the cleaning process.

Influence of gamma radiation and EMS on chlorophyll and macro-mutation in mungbean (Vigna radiata)

Present study was carried during rainy (kharif) season of 2021 (M1 generation), summer 2022 (M2 generation) and rainy (kharif) seasons of 2022 (M3 generation) at College of Agriculture, Swami Keshwanand Rajasthan Agricultural University, Bikaner, Rajasthan for creating genetic variability in mungbean [Vigna radiata (L.) R. Wilczek]. The experiment was conducted with 26 treatments and 2 popular archaic varieties of mungbean (Ganga-1 and GM-4), solitary application of gamma radiation (200, 400 and 600 Gy), and ethyl methane sulphonate (EMS) (0.1 and 0.2%) as well as their combinations. A wide spectrum of chlorophyll mutants (Chlorina, Xantha, Albina, Viridis and complex type) and morphological mutants (plant type, flower colour, pod type, leaf variation and maturity period) were identified at various crop growth stages. All mutagen treatments including solitary application of gamma radiation and EMS as well as their combinations were found effective for creating genetic variability. The lower concentration of EMS (0.1%) was found to be relatively more effective as compared to 0.2%. Similarly, the lower dose of gamma radiation (200 Gy) was also more effective than 400 and 600 Gy. Among all the treatment combinations, combined application of 200 Gy + 0.1% EMS was found most effective in generating chlorophyll and morphological mutants. Among two varieties of mungbean, Ganga-1 was found to be more sensitive to mutagens as compared to GM-4. Numerous mutants identified in the mutagenized population of both varieties exhibited stability and superiority in terms of agro- morphological traits over Ganga-1 and GM-4. A mutant (S-92 of GM-4) identified during M1 in mutagen treatment 0.1% EMS was very deep lobbed which altered the plant morphology and appearance. This novel unique mutant identified in M1 generation maintained its stability in M2 and M3 generations also. The leaf colour of this mutant was darker than the original leaf colour of GM-4 and found relatively more tolerant to soil moisture-deficit stress.

Sustainable and fast synthesis of zinc-phthalocyanine for gamma radiation dosimeter application

In the present research, the two different systems of dye based on zinc phthalocyanine were prepared by microwave-induced synthesis and conventional methods. They were evaluated as new effective chemical-based dosimeters for gamma irradiation. The sensitivity of the prepared dosimeters was examined by studying the comparative results between them through the changes in structural and optical properties upon exposure to different gamma irradiation doses. The color bleaching of the solutions was followed spectrophotometrically. Gradual changes from blue to light yellow color of zinc phthalocyanine solution, with the increase of the gamma radiation dose, were observed due to the decomposition of the dyes based on the zinc phthalocyanine. The synthesized zinc phthalocyanine chemical-based dosimeters for measurement of gamma irradiation up to 25kGy showed excellent stability after irradiation in terms of morphology and structure, which makes them a suitable novel material as composite-based dosimeters of gamma irradiation.

Assessment of radiation-induced sterility, longevity, and reproductive characteristics of the Aedes aegypti (Diptera: Culicidae) strain of Swat: A step towards the implementation of SIT in Pakistan.

Biological approaches for vector mosquito control such as sterile insect technique (SIT) requires sterilization of male mosquitoes through specific radiation doses for sterility induction in males. Under the SIT program, the males used must be compatible with the wild males in vigor, flight and selection of mate. Much of this potential is determined by the diet provided in the larval stages and optimizing the irradiation doses that cause complete sterility but have very minimal effect on the lives of irradiated males. The current study is designed to evaluate gamma radiation doses for inducing sterility in male Aedes aegypti mosquitoes with a genomic background from Pakistan (Swat district) and to assess the effects of radiation exposure on the competency of irradiated males and other life traits of irradiated mosquitoes. Sterilization of 17-hour-old male pupae (groups of 50 pupa/cup in three replicates) of the Ae. aegypti Swat strain was conducted using radiation doses of 30, 60, 70, 90, and 105 gray (Gy) from (Co60) at the Nuclear Institute for Food and Agriculture (NIFA) in Peshawar, Pakistan. Post-irradiated pupae were released in adult cages. Virgin females of the same cohort were released (1:1) to mate with the irradiated males. Mortality, longevity, mating competitiveness of males, and female fecundity were recorded. An average of 71 eggs per female was recorded in control with 86% hatch rate. Individual females mated with a 60 Gy treated males produced 60 ± 0.6 eggs per female with 17% hatch rate, and those mated with 70 Gy males produced 42 ± 0.01 eggs with a nil hatch rate, whereas females mated with males treated with ≥70 Gy doses did not reproduce to next generation. Females in groups of 50 mated with 60, 70 Gy treated males (equal pairs), produced 369±1.3 and 98±0.01 eggs with 15% and zero hatch rate. Significant dose dependent reduction in longevity was observed for >30 Gy doses. The matting competence of irradiated males was about half that of un-irradiated males. Aedes aegypti with a Pakistani genomic background treated with a ≥70 Gy dose of gamma radiation induced complete sterility in males and provided the first- step foundation for SIT application in Pakistan. Further extensive studies are required to optimize the SIT techniques so that fully sterile males with very minor quality changes can be produced on large scales for field trials.