Fast neutron irradiation long term effect on Ocimum basilicum germination and initial vegetative parameters

The goal of this study is to assess the long-term (3-year) effects of rapid neutron irradiation using an Americium-Beryllium source on two generations (M0 and M1) of Ocimum basilicum commercial trait. Seeds of each variety and generation were irradiated with 0, 7.5, 20, 40, and 50 Gray in 2018, and then seeded in 2021 – with their corresponding controls – to see how the different irradiation treatments affected germination and early vegetative metrics three years after irradiation. In the first generation, no significant changes between the treatments were seen. Increased irradiation dosage resulted in a significant decrease in germination % in the second generation (M1), but a significant increase in seedling height. The M0 generation seedlings, on the other hand, were substantially shorter than controls. In the M0 generation, the higher dosages (40 and 50 Gray) were deadly, and seedlings were terminated 7–10 days after germination. The irradiation dose of 20 Gray was shown to be the most successful in inducing viable and beneficial alterations for phenotypic characteristics in basil. When compared to control plants, the lower (7.5 and 20 Gray) bombardment generated leaf anomalies such as smaller leaves and internodes, a split apex, and a ribbon-like stem.

Effect of γ-ray irradiation on performance of LiNbO(3)-based piezoelectric vibration sensors

LiNbO3 (LN)-based micro-electro-mechanical systems (MEMS) vibration sensors exhibit giant prospection in extreme environments, where exist a great amount of irradiation. However, to the best of our knowledge, it is still unknown whether the irradiation affects the performance of LN-based piezoelectric MEMS sensors. Based on this consideration, it is necessary to model the irradiation environment to investigate the effect of high dosage irradiation on LN-based vibration sensors. Firstly, the theoretical work is done to study the Compton Effect on the Gamma-ray irradiation with Co-60 source. After irradiation, X-ray diffraction (XRD) characterization was performed to verify the effect of irradiation on the crystalline of LN thin film. Meanwhile, the performances of output voltages on the five MEMS devices under various dosage of irradiation are compared. As a result, a neglected shift of 0.02 degrees was observed from the XRD image only under maximum irradiation dosage of 100 Mrad(Si). Moreover, the output voltages of cantilever-beam vibration sensors decrease by 3.1%. Therefore, it is verified that the γ-ray irradiation has very little influence on the LN-based MEMS vibration sensors, which have great attraction on the materials and sensors under high-dose irradiation.

Diet-Related Phototoxic Reactions in Psoriatic Patients Undergoing Phototherapy: Results from a Multicenter Prospective Study

Vegans and vegetarians often consume foods containing photosensitizers capable of triggering phytophotodermatitis. The potential effect of vegan and vegetarian diets on the response of psoriatic patients undergoing phototherapy is not well characterized. We assessed clinical outcomes of vegan, vegetarian and omnivore adult psoriatic patients undergoing band ultraviolet B phototherapy (NB-UVB). In this multicenter prospective observational study, we enrolled 119 adult, psoriatic patients, of whom 40 were omnivores, 41 were vegetarians and 38 were vegans, with phototherapy indication. After determining the minimum erythemal dose (MED), we performed NB-UVB sessions for 8 weeks. The first irradiation dosage was 70.00% of the MED, then increased by 20.00% (no erythema) or by 10.00% (presence of erythema) until a maximum single dose of 3 J/cm2 was reached and constantly maintained. All the enrolled patients completed the 8 weeks of therapy. Severe erythema was present in 16 (42.11%) vegans, 7 (17.07%) vegetarians and 4 (10.00%) omnivores (p < 0.01). MED was lowest among vegans (21.18 ± 4.85 J/m2), followed by vegetarians (28.90 ± 6.66 J/m2) and omnivores (33.63 ± 4.53 J/m2, p < 0.01). Patients with severe erythema were more likely to have a high furocumarin intake (OR 5.67, 95% CI 3.74–8.61, p < 0.01). Vegans consumed the highest amount of furocumarin-rich foods. A model examining erythema, adjusted for gender, age, skin type, MED, phototherapy type, number of phototherapies and furocumarin intake, confirmed that vegans had a lower number of treatments. Vegans had more frequent severe erythema from NB-UVB, even after adjustment of the phototherapy protocol for their lower MED. Assessing diet information and adapting the protocol for vegan patients may be prudent.

The Relationship of the Efficiency of Energy Conversion Into Growth as an Indicator for the Determination of the Optimal Dosage for Mutation Breeding With the Appearance of Chromosomal Bridges, Ring Chromosomes, Micronuclei and Incomplete Mitosis After Gamma Irradiation of Kernels of Triticum Turgidum Ssp. Durum L. Cultivar Orania

BackgroundA 50% growth reduction of seedling height (GR50) after acute gamma irradiation of dormant kernels is widely used as a measure of irradiation damage to obtain the ideal irradiation dosage for mutation breeding. It became clear in recent years that the GR50 is not sensitive enough to predict the ideal gamma irradiation dosage for mutation breeding and it predicts a value that is higher than ideal. The study aim was to determine whether root, shoot and seedling growth on the one side and the efficiency of energy conversion into growth on the other are measuring different growth retardation effects of gamma irradiation that are the result of DNA damage (bridges, ring chromosomes, micronuclei, incomplete mitosis) in Triticum turgidum ssp. durum. If the efficiency of energy conversion into growth is measuring different effects, the usefulness of efficiency of energy conversion into growth to predict the optimal dosage for mutation breeding will be investigated. ResultsThe kernels were gamma irradiated from 50 - 350 Gy using a 60Cobalt source. The kernels were left to germinate and grow for a period of 132 hours for the shoot and root growth and the efficiency of energy conversion into growth determination and for a period of 47.5 hours for the determination of the number of bridges, ring chromosomes, micronuclei and incomplete mitosis. The control differed highly significantly from 50 Gy and higher dosages and from 250 Gy and higher dosages for root and shoot growth respectively and from 250 Gy for the efficiency of energy conversion into growth. There was a highly significant increase in the number of bridges and micronuclei between 50 Gy and 150 Gy together with the higher irradiation dosages and only from 250 Gy for the ring chromosomes and interphase cells with incomplete mitosis. Root and seedling growth on the one hand and the efficiency of energy conversion into growth on the other were found to be measuring different effects of gamma irradiation on plant growth. ConclusionThe optimal dosage for mutation breeding was determined by making use of the efficiency of energy conversion into growth.

Impact of UV irradiation on disinfection by-product formation and speciation from post-chlorination of dissolved organic matter

The objective of this study was to investigate the effects of combined low-pressure ultraviolet (UV)irradiation and chlorination on the formation of disinfection by-products (DBPs) from different dissolved organic matter (DOM) as DBP precursors. Commercially available humic acid (HA), extracellular organic matter (EOM) from green algae, cyanobacteria, and diatom, namely Scenedesmus quadricauda (SQ), Merismopedia sp. (Msp), and Phaedactylum tricornutum (PT), were used as the sources of DOM. The DBP formation increased with increasing total residual chlorine; EOM from PT presented the highest formation potential followed by HA, Msp, and SQ. The low dosage of 40 mJ/cm2 UV irradiation is insignificant to change the DBP formation from HA and SQ; however, it decreased the DBP formation from bromide-containing EOM of PT and promoted the DBP formation from EOM of Msp at various total residual chlorines. The DBP formation of each DOM correlated well with total residual chlorine. The maximum DBP formation potential (DBPFP) reduction of 42.25 and 13.75% for haloacetic acid formation potential (HAAFP) and trihalomethane formation potential (THMFP) was obtained at the UV irradiation dosage of 300 mJ/cm2 for EOM of PT. However, for the EOM derived from Msp, a maximum increase of 58.1 and 51.1% for HAAFP and THMFP was observed after UV-chlorination.

KERAGAAN KEDELAI (Glycine max (L) merril) GENERASI M1 VARIETAS ANJASMORO HASIL RADIASI SINAR GAMMA

The purpose of this research was to find out the diversity of Anjasmoro variety soybean of M1 generation resulted from gamma-ray radiation on its various phenotype characters. A total of 300 seeds were radiated with Isotope and Radiation Technology Application from National Nuclear Power Agency at Pasar Jumat, South Jakarta, then planted in the experimental garden of Agriculture Faculty, Riau University. The dosage of irradiation used was 100 Gy, 150 Gy, 200 Gy, and 250 Gy also M0 as an ancestor. The quantitative and qualitative observation was made as such flowering age, harvest age, plant height, amount of seeds per plant, seeds weight per plant and growth type. The data were analyzed with variance analysis then continued with Duncan’s New Multiple Range Test on a 5% level. The diversity component was analyzed with homogeneity of variance according to the Levene test procedure. The result shows gamma-ray radiation is causing diversity on Anjasmoro variety on quantitative characters such as flowering age, harvest age and seed weight per plant. The vast diversity has happened on irradiation dosage of 200Gy.

LOCAL NANO-MECHANICAL PROPERTIES OF CROSS-LINKED POLYBUTYLENE

Cross-linking is a process in which polymer chains are associated through chemical bonds. The cross-linking level can be adjusted by the irradiation dosage and often by means of a cross-linking booster. The polymer additional cross-linking influences the surface nano and micro layers in the way comparable to metals during the thermal and chemical-thermal treatments. Polybutylene terephthalate (PBT) can be found in a group of structural polymers, which are often used in industry, especially in automotive. Applying the technology of electron radiation induces a creation of 3D network structure, which improves the local mechanical properties. These were later measured by a depth sensing indentation (DSI) test. This state of the art method is based on immediate detection of indentation depth in relation to applied force. The creation of 3D network caused an increase in nano-mechanical properties values, such as indentation hardness and indentation modulus, in comparison to the virgin material. The indentation hardness rose by 80%, while the indentation modulus elevated by 62%. The selected structural materials, e.g. PBT, were modified by the electron irradiation in a positive way and as such could be moved to a group of high performance materials.

Induction of Variability in Three Nigerian Pepper Varieties using Gamma Irradiation

This study was aimed at inducing mutation on three cultivars of Capsicum annuum L. to source for new and favourable genetic variations that could be exploited for better agronomic traits. The mutation was induced by exposing the seeds of Shombo, Tatase and Nsukka yellow pepper to varied dosages (0, 50, 100, 150 and 200 Gy from 60Co source) of gamma irradiation. The study was conducted in the Botanic Garden of the University of Nigeria. Seeds exposed to 50Gy produced significantly (P < 0.05) the highest number of fruits per plant, highest fruit yield and improved morphological traits in Shombo. Higher dosages of irradiation gave lower fruits per plant and yields than untreated seeds in Shombo. Tatase irradiated with 150 Gy had significantly the highest single fresh fruit weight. Generally in Tatase 50, 100 and 150Gy increased some morphological traits significantly (P < 0.05). Although 50 Gy gave highest number of fruits per plant, 100, 150 and 200Gy had significantly higher fruit yield with yield increasing as dosage increased. For Nsukka yellow, irradiation did not show a consistent pattern in improving morphological traits. But 200Gy produced significantly the highest number of fruits per plant and highest yield. Gamma irradiation dosage of 50 – 200 Gy can be exploited to create variability for improvement of morphological and yield traits in pepper plants.

Geological alteration of organic macromolecules by irradiation: Implication for organic matter occurrence on Mars

The harsh radiation environment on Mars is widely believed to destroy organic matter, but elucidating the systematic degradation pathway and its controlling factors has proved elusive. Here we show the alteration of macromolecular organic matter in the ∼500-m.y.-old uranium-rich Alum Shale Formation (northwestern Europe), which is suggested as a geological analogue on Earth of the Martian surface samples, in response to ⟨-particle irradiation. The composition and quantity of pyrolysates as well as the extractability of immature Alum Shale are governed by uranium content, and this has been confirmed independently using uranium-rich shales of younger geological age. During the course of irradiation, macromolecules undergo cross-linking, demethylation, and aromatization processes, which are active at different stages in the alteration of the organic matter. A comparison of the Martian surface samples with Kolm (carbonaceous nodules with very high uranium content intercalated in the Alum Shale) samples in terms of irradiation dosage and organic geochemical characteristics reveals that they have received similar levels of irradiation. A model of the radiation-induced alteration of organic matter has been developed, which opens a window for understanding the possible pristine nature and composition of the irradiated organic matter on Mars and offers arguments to qualitatively predict potential organic matter in the Martian paleo-lacustrine subsurface.