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Mechanisms of interaction of ionizing radiation with biological objects are a chain of successive physical and physico-chemical changes, which manifest themselves in the form of excitation, primary and secondary ionization of molecules. Biosynthesis of ATP, which is carried out by a system of oxidation-reduction enzymes localized in the inner membrane of mitochondria - the respiratory chain, belongs to the vital processes that are directly disturbed under the action of ionizing radiation. The high degree of damage to this system is due to the significant radiosensitivity of metal-containing enzymes. The purpose of the work is to study the formation of the adaptive response of muscle tissue of sexually mature rats to the influence of ionizing radiation at a dose of 0.5 Gy. It was concluded that a day after irradiation with the dose of 0.5 Gy, the content of contractile proteins in skeletal muscle decreases slightly. On the 15th day, the content of contractile proteins began to decrease. By the 30th day, the content of contractile proteins decreased by 22.9% for myosin, by more than 11% for actin, and by 7 and 8% for troponin and tropomyosin, respectively, compared to the values of the intact group. A similar picture is observed in the cardiac muscle. Mg2+,Ca2+-ATP-ase activity of actomyosin, starting from the 1st day was shown to be increased in both the skeletal and cardiac muscles, reaching its peak in the cardiac muscle on the 15th day, in contrast to the skeletal muscle, where this indicator reached its peak on the 7th day. The authors conclude that irradiation of sexually mature animals with the dose of 0.5 Gy forms an adaptive response that is accompanied by an increase in Mg2+,Ca2+-ATP-ase activity due to the formation of a strong form of binding between F-actin and myosin, actin monomers go into the typical for actomyosin “turned on stage”, and the myosin heads acquire an ordered orientation in the muscle fiber. According to author’s idea, the data obtained indicated the benefit and reasonability of using in post-radiation dysfunctions complex pharmacological treatment drugs that are able to normalize intracellular homeostasis, eliminate probable acidic changes initiated by radiation exposure, activate the processes of intramuscle energy generation and which have protective properties in relation to the muscular system.

Biochemical processes occurring in a living organism take part in the development of radiation-induced structural disorders, realizing primary damage. As a result, morphological manifestations of radiation damage are preceded by chemical shifts determining them. In the descendants of animals irradiated in different doses, a decrease in physical performance is observed, which is due to a violation of the efficiency of the use of the unique biosubstrate of muscle tissue - creatinephosphate, a change in the ratio of the activity of aerobic and anaerobic metabolism, and processes of trans-deamination of amino acids. The purpose of the work is to investigate the the mechanisms of disruption of metabolic processes in the muscle tissue of the descendants of irradiated animals. It was concluded that, unlike skeletal muscle, the activity of the tricarboxylic acid cycle, in particular the NAD-dependent malate dehydrogenase, in the myocardium is quite significant both in the cytoplasm and in the mitochondria of the tissue, as evidenced by the higher level of tricarboxylic acid cycle metabolites acids - malic and oxaloacetic, as well as the activity of NADP-dependent malate dehydrogenase, which performs a connecting role between glycolysis and the cycle of tricarboxylic acids in providing them with metabolites and transferring protons from NADH+H+ to NADP. The author revealed that myocardium is characterized by a larger pool of adenyl nucleotides due to ATP. Tha data obrtained shiowed hyperglycemia which is observed in the blood of the descendants of irradiated animals. Gluconeogenesis is enhanced in the liver of the descendants of irradiated animals and this explains the hyperglycemia and accumulation of glycogen in the liver. At the same time, the penetration of glucose into muscle cells is weakened, which is associated with a decrease in their glycogen content, and this can be explained by the decrease in adaptation to physical exertion in the descendants of irradiated animals. The author made a cionclusion that the pathophysiological mechanisms of radiation-induced energy supply restructuring are aimed at short-term processes of strengthening the supply of energy to vital organs and systems for destroyed biochemical, physiological, functional and regulatory processes restoration and sanogenetic mechanisms activation.

Antibiotic resistance has been a serious health threat of widespread concern, as antibiotics are difficult to degrade effectively in the environment. In this study, sulfamethoxazole (SMZ), a common antibiotic in an aqueous solution, was irradiated by low-energy X-ray to investigate the effect of the absorption dose, initial concentration, initial pH, irradiation energy and other conditions on the degradation of SMZ, as well as the kinetic mechanism of SMZ degradation. The results showed that low-energy X-ray irradiation could effectively degrade SMZ in an aqueous solution at different initial concentrations and acid-base degrees, and the degradation effect of irradiation in the range of 60–80 keV is independent of the energy of X-rays. The degradation rate of the SMZ solution, with an initial concentration of 10.70 mg/L, was 94.6% at an absorbed dose of 890 Gray, with a pH of 3.5. Similar to other works on the degradation of antibiotics by ionizing irradiation, the degradation of SMZ solutions conformed to a pseudo-first-order kinetic mechanism. [ABSTRACT FROM AUTHOR]

An urgent problem today is not only the study of changes in the stability of the genome of somatic cells, the clarification of the mechanisms of its destabilization under the influence of a complex of environmental factors, including radiation, but also the study of the possibility of hereditary transmission of these changes. In the modern experimental and clinical medicine, the most important problem is the harmful effect of ionizing radiation on the descendants of irradiated parents and the specifics of the effect of radiation on the developing organism. An important aspect of the problem of long-term post-radiation effects is the state of reproductive function and health of the descendants of the irradiated population, due to the physiological characteristics inherent to the mother and child - high sensitivity to the action of ionizing radiation, the consequences of which may manifest after a long period of imaginary well-being. The purpose of the work is to investigate the dynamics of body weight and hematological indiexes in the descendants of intact sexually mature animals and descendants born to animals irradiated at different doses, which were exposed to radiation at a dose of 1.0 Gy. The authors revealed that in descendants born to animals irradiated at different doses, which were exposed to radiation at a dose of 1.0 Gy, it was established that by the 30th day after irradiation at a dose of 1.0 Gy, the general condition of pup rats born from animals irradiated at a dose of 0.5 Gy and exposed to irradiation at a dose of 1.0 Gy is satisfactory against the background of an insignificant decrease in the body weight. This also applies to pup rats born to animals irradiated at a dose of 1.0 Gy, whose general condition slightly improves compared to the previous period of the study. The data obtained showed in the peripheral blood after 1 day in the descendants born to animals irradiated at a dose of 0.5 Gy, after irradiation at a dose of 1.0 Gy, a reduced content of hemoglobin and erythrocytes against the background of an increase in the content of platelets, leukocytes, lymphocytes and reticulocytes in comparison with non-irradiated animals, which was maintained throughout the experiment. Pronounced changes in hematological parameters were observed in the descendants born to animals irradiated at a dose of 1.0 Gy, which were exposed to total γ-irradiation at a dose of 1.0 Gy. The authors suppose their data are in favour of the pronounced adaptationof organisms’ regulatiory systems to ionizing irradiation effect that, firstly, outline the adaptative physiologcal mechanisms and, secondly, show the main launches of pathophysiologcial mechamisns in case of irradiation-induced hematological changes.

Radiotherapy is widely used for the treatment of breast cancer. However, we have shown that ionizing radiation can provoke premature senescence in breast stromal cells. In particular, breast stromal fibroblasts can become senescent after irradiation both in vitro and in vivo and they express an inflammatory phenotype and an altered profile of extracellular matrix components, thus facilitating tumor progression. Adipose‐derived stem cells (ASCs) represent another major component of the breast tissue stroma. They are multipotent cells and due to their ability to differentiate in multiple cell lineages they play an important role in tissue maintenance and repair in normal and pathologic conditions. Here, we investigated the characteristics of human breast ASCs that became senescent prematurely after their exposure to ionizing radiation. We found decreased expression levels of the specific mesenchymal cell surface markers CD105, CD73, CD44, and CD90. In parallel, we demonstrated a significantly reduced expression of transcription factors regulating osteogenic (i.e., RUNX2), adipogenic (i.e., PPARγ), and chondrogenic (i.e., SOX9) differentiation; this was followed by an analogous reduction in their differentiation capacity. Furthermore, they overexpress inflammatory markers, that is, IL‐6, IL‐8, and ICAM‐1, and a catabolic phenotype, marked by the reduction of collagen type I and the increase of MMP‐1 and MMP‐13 expression. Finally, we detected changes in proteoglycan expression, for example, the upregulation of syndecan 1 and syndecan 4 and the downregulation of decorin. Notably, all these alterations, when observed in the breast stroma, represent poor prognostic factors for tumor development. In conclusion, we showed that ionizing radiation‐mediated prematurely senescent human breast ASCs have a decreased differentiation potential and express specific changes adding to the formation of a permissive environment for tumor growth. [ABSTRACT FROM AUTHOR]

Multimodal treatment approaches, such as radio-immunotherapy, necessitate regimen optimization and the investigation of the interactions of different modalities. The aim of this study was two-fold. Firstly, to select the most effective combination of irradiation and the previously developed tumor cell-based vaccine and then to provide insight into the immune response to the selected combinatorial treatment. The study was performed in immunologically different murine tumor models: B16F10 melanoma and CT26 colorectal carcinoma. The most effective combinatorial treatment was selected by comparing three different IR regimens and three different vaccination regimens. We determined the local immune response by investigating immune cell infiltration at the vaccination site and in tumors. Lastly, we determined the systemic immune response by investigating the amount of tumor-specific effector lymphocytes in draining lymph nodes. The selected most effective combinatorial treatment was 5× 5 Gy in combination with concomitant single-dose vaccination (B16F10) or with concomitant multi-dose vaccination (CT26). The combinatorial treatment successfully elicited a local immune response at the vaccination site and in tumors in both tumor models. It also resulted in the highest amount of tumor-specific effector lymphocytes in draining lymph nodes in the B16F10, but not in the CT26 tumor-bearing mice. However, the amount of tumor-specific effector lymphocytes was intrinsically higher in the CT26 than in the B16F10 tumor model. Upon the selection of the most effective combinatorial treatment, we demonstrated that the vaccine elicits an immune response and contributes to the antitumor efficacy of tumor irradiation. However, this interaction is multi-faceted and appears to be dependent on the tumor immunogenicity. [ABSTRACT FROM AUTHOR]

In our study, our aim was to examine the cytotoxic and radio-sensitizing effect of the alkaloid piperine, a major pungent of black pepper, on two different human epithelial tumor cell lines in vitro. The growth of the human cell lines T98G (glioblastoma) and FaDu (hypopharyngeal carcinoma) was examined under the influence of piperine in different concentrations. In addition, after combined treatment with ionizing radiation, long-term survival was investigated with a colony formation assay. The proliferation was analyzed using the BrdU-assay, while the DNA repair capacity was examined via the γH2AX assay. Piperine reduced the growth of both cell lines in a concentration-dependent manner as well as a time-dependent one. After combined treatment with piperine and ionizing radiation, an inhibition of clonogenic survival could be proven. A reduced proliferation capacity and an additive effect on DNA damage 24 h after irradiation are possible causal mechanisms, which were also demonstrated for both cell lines. Based on the results presented in this study, piperine was shown to have cytotoxic antitumor activity and a radio-sensitizing effect in micromolar concentrations in the human tumor cells that were tested. Based on these results piperine represents a potential therapeutic option in radio-oncological treatment. [ABSTRACT FROM AUTHOR]

Simple Summary: Ionizing radiation exposure of the circulatory system occurs at various dose rates. Our previous work showed sparing and enhancing effects of dose protraction for aortic changes in wild-type mice at 6 months after starting acute, intermittent, or continuous irradiation with 5 Gy of photons. Here we report that irradiation produces qualitatively similar albeit quantitatively less aortic changes at 12 months than at 6 months after stating irradiation. The magnitude of changes at 12 months was not smaller in 25 fractions (Frs), but was smaller in 100 Frs and chronic exposure, than acute exposure. The magnitude at 6 and 12 months was greater in 25 Frs, smaller in 100 Frs, and much smaller in chronic exposure, compared with acute exposure. These findings suggest that dose protraction changes aortic damage, in a manner that depends on post-irradiation time and is not a simple function of dose rate. In medical and occupational settings, ionizing irradiation of the circulatory system occurs at various dose rates. We previously found sparing and enhancing dose protraction effects for aortic changes in wild-type mice at 6 months after starting irradiation with 5 Gy of photons. Here, we further analyzed changes at 12 months after stating irradiation. Irrespective of irradiation regimens, irradiation little affected left ventricular function, heart weight, and kidney weight. Irradiation caused structural disorganizations and intima-media thickening in the aorta, along with concurrent elevations of markers for proinflammation, macrophage, profibrosis, and fibrosis, and reductions in markers for vascular functionality and cell adhesion in the aortic endothelium. These changes were qualitatively similar but quantitatively less at 12 months than at 6 months. The magnitude of such changes at 12 months was not smaller in 25 fractions (Frs) but was smaller in 100 Frs and chronic exposure than acute exposure. The magnitude at 6 and 12 months was greater in 25 Frs, smaller in 100 Frs, and much smaller in chronic exposure than acute exposure. These findings suggest that dose protraction changes aortic damage, in a fashion that depends on post-irradiation time and is not a simple function of dose rate. [ABSTRACT FROM AUTHOR]

Multimodal treatment approaches, such as radio-immunotherapy, necessitate regimen optimization and the investigation of the interactions of different modalities. The aim of this study was two-fold. Firstly, to select the most effective combination of irradiation and the previously developed tumor cell-based vaccine and then to provide insight into the immune response to the selected combinatorial treatment. The study was performed in immunologically different murine tumor models: B16F10 melanoma and CT26 colorectal carcinoma. The most effective combinatorial treatment was selected by comparing three different IR regimens and three different vaccination regimens. We determined the local immune response by investigating immune cell infiltration at the vaccination site and in tumors. Lastly, we determined the systemic immune response by investigating the amount of tumor-specific effector lymphocytes in draining lymph nodes. The selected most effective combinatorial treatment was 5× 5 Gy in combination with concomitant single-dose vaccination (B16F10) or with concomitant multi-dose vaccination (CT26). The combinatorial treatment successfully elicited a local immune response at the vaccination site and in tumors in both tumor models. It also resulted in the highest amount of tumor-specific effector lymphocytes in draining lymph nodes in the B16F10, but not in the CT26 tumor-bearing mice. However, the amount of tumor-specific effector lymphocytes was intrinsically higher in the CT26 than in the B16F10 tumor model. Upon the selection of the most effective combinatorial treatment, we demonstrated that the vaccine elicits an immune response and contributes to the antitumor efficacy of tumor irradiation. However, this interaction is multi-faceted and appears to be dependent on the tumor immunogenicity.

It is well established that cohorts of individuals exposed to ionizing radiation exhibit increased risks for cardiovascular diseases. Currently, the role of immune system in pathogenesis of atherosclerosis is actively studied. Meanwhile, the immunomodulatory effects of irradiation in pathogenesis of atherosclerosis in the persons exposed to ionizing radiation still remain unclear. The aim of this research was to study the effect of ionizing radiation upon lymphocyte subpopulations involved in pathogenesis of atherosclerosis. The lymphocyte subpopulations were studied in peripheral blood of the workers chronically exposed to occupational combined radiation versus a control group. The study considered 72 workers of the Russian nuclear production facility, the Mayak Industrial Association (mean age of 72.1±10.9 years), and 72 control individuals (mean age of 70.7±9.2 years). All the workers were chronically exposed to combined radiation (external gamma-rays and internal alpha-particles). The mean cumulative dose absorbed by red bone marrow from external gamma-ray exposure was 0.750±0.699 Gy; the mean cumulative absorbed dose to red bone marrow from internal alpha-particles was 0.072±0.092 Gy. The relative and absolute numbers of lymphocyte subpopulations (total T-cells, T-helpers, T-cytotoxic, total B-cells, NK-cells and T-NK-cells) were detected by flow cytofluorometry. The absolute number of CD3+CD19+T-lymphocytes was significantly lower in the individuals exposed to chronic irradiation, compared with the controls (1658.8±694.3 x 106/l and 1988.4±1045.4 x 106/l, respectively). The relative number of CD3+CD4+T-helpers and CD3+CD8+T-cytotoxic lymphocytes was significantly higher in individuals exposed to chronic irradiation. Relative number of T-helpers in the main group was 42.4±8.8% vs 35.3±8.7% in controls; the relative number of T-cytotoxic lymphocytes was 27.6±9.5%, and 23.3±6.5%, respectively. A significant negative correlation was revealed between absolute number of T-lymphocytes and cumulative absorbed doses to bone marrow from external gamma irradiation (correlation quotient r = -0,53565, p = 0,000001) and internal alpha sources (r = -0.54804, p = 0.0000006). This correlation may indicate a relationship between these changes (decreased absolute numbers of T cells) and occupational exposure rates. The increased relative number of T-helpers and cytotoxic T-lymphocytes confirm an assumption that specific antigens may cause an enhanced immune response during the development of atherosclerosis in exposed individuals.

• Optical fiber based method for real-time monitoring of thin film optical properties when exposed to gamma radiation. • Long period grating (LPG) inscribed in a radiation resistant optical fiber, which is coated with the thin film to be analyzed. • Tested for metal oxide thin films, i.e., Al 2 O 3 , TiO 2 and Ta 2 O 5 , as well as a polymeric film, namely polystyrene. In this work, we report an all-optical-fiber-based method to monitor in real-time the changes in thin film optical properties when exposed to harsh environments such as high doses of gamma radiation. The method is based on a long period grating (LPG) inscribed in a radiation resistant optical fiber, which is coated with a thin film to be analyzed. Due to impact of the environment on the film properties, the transmission spectrum of the LPG changes. To validate this methodology, we deposited oxides of various metals, i.e. aluminum (Al 2 O 3), titanium (TiO 2), and tantalum (Ta 2 O 5), as well as a polymeric film, namely polystyrene (PS), on the LPG surface and measured the resonant wavelength shift induced by high doses of gamma exposure (dose rate of 2.3 kGy/h, up to a total dose of 46 kGy). The changes could be observed in real-time up to maximum reached dose and during the recovery period. The results are significantly dependent on thin film material. Among the oxides, TiO 2 thin film demonstrated the highest susceptibility to irradiation, whereas Al 2 O 3 exhibited the least impact. Additionally, a good recovery potential for Ta 2 O 5 thin film was observed, hinting at its promising application in dosimetry. Conversely, the PS film exhibited a permanent effect induced by irradiation. This is the first real-time experimental study of the impact of high dose gamma radiation on thin film optical properties using a universal optical-fiber-based device. The findings pave the way for assessing radiation hardness of thin film materials or utilizing such a method to optimize material treatment involving ionizing radiation. [ABSTRACT FROM AUTHOR]

Simple Summary: Factors secreted from irradiated mesenchymal stromal cells (MSC) may exert genotoxic effects in human CD34+ cells, thereby potentially contributing to the pathogenesis of hematologic disorders such as leukemias. In a proteomics approach, we recently identified four key proteins in the secretome of X-ray-irradiated MSC, among them the three chaperones GRP78, CALR, and PDIA3, and one glycolytic enzyme GPI. Here, we demonstrate that recombinant GRP78, CALR, PDIA3 and GPI induce significant levels of genetic instability in human CD34+ cells. Our data suggest that GRP78, CALR, PDIA3 and GPI released from irradiated MSC act as mediators of genetic instability in human CD34+ cells with potential implications for radiation-induced hematologic disorders. Soluble factors released from irradiated human mesenchymal stromal cells (MSC) may induce genetic instability in human CD34+ cells, potentially mediating hematologic disorders. Recently, we identified four key proteins in the secretome of X-ray-irradiated MSC, among them three endoplasmic reticulum proteins, the 78 kDa glucose-related protein (GRP78), calreticulin (CALR), and protein disulfide-isomerase A3 (PDIA3), as well as the glycolytic enzyme glucose-6-phosphate isomerase (GPI). Here, we demonstrate that exposition of CD34+ cells to recombinant GRP78, CALR, PDIA3 and GPI induces substantial genetic instability. Increased numbers of γH2AX foci (p < 0.0001), centrosome anomalies (p = 0.1000) and aberrant metaphases (p = 0.0022) were detected in CD34+ cells upon incubation with these factors. Specifically, γH2AX foci were found to be induced 4–5-fold in response to any individual of the four factors, and centrosome anomalies by 3–4 fold compared to control medium, which contained none of the recombinant proteins. Aberrant metaphases, not seen in the context of control medium, were detected to a similar extent than centrosome anomalies across the four factors. Notably, the strongest effects were observed when all four factors were collectively provided. In summary, our data suggest that specific components of the secretome from irradiated MSC act as mediators of genetic instability in CD34+ cells, thereby possibly contributing to the pathogenesis of radiation-induced hematologic disorders beyond direct radiation-evoked DNA strand breaks. [ABSTRACT FROM AUTHOR]

(1) Background: The systemic administration of therapeutic agents to the intestine including cytokines, such as Interleukin-22 (IL-22), is compromised by damage to the microvasculature 24 hrs after total body irradiation (TBI). At that time, there is significant death of intestinal microvascular endothelial cells and destruction of the lamina propria, which limits drug delivery through the circulation, thus reducing the capacity of therapeutics to stabilize the numbers of Lgr5+ intestinal crypt stem cells and their progeny, and improve survival. By its direct action on intestinal stem cells and their villus regeneration capacity, IL-22 is both an ionizing irradiation protector and mitigator. (2) Methods: To improve delivery of IL-22 to the irradiated intestine, we gavaged Lactobacillus-reuteri as a platform for the second-generation probiotic Lactobacillus-reuteri-Interleukin-22 (LR-IL-22). (3) Results: There was effective radiation mitigation by gavage of LR-IL-22 at 24 h after intestinal irradiation. Multiple biomarkers of radiation damage to the intestine, immune system and bone marrow were improved by LR-IL-22 compared to the gavage of control LR or intraperitoneal injection of IL-22 protein. (4) Conclusions: Oral administration of LR-IL-22 is an effective protector and mitigator of intestinal irradiation damage. [ABSTRACT FROM AUTHOR]

A quantitative model of the size effect, i.e., the dependence of surface states on the gate size, in metal—oxide—semiconductor (MOS) structures subjected to ionizing irradiation is developed. It is assumed that the size effect is induced by the escape of hydrogen released from hydrogen-containing hole traps through the ends of a two-dimensional MOS structure. The effect is described by a system of diffusion–kinetic equations solved together with the Poisson equation. The influence of processing treatments and thermal-oxidation modes on the magnitude of the effect is associated with different concentrations of hydrogen-containing traps in the gate oxide. It is shown that the main contribution to the effect is introduced by the diffusion of neutral hydrogen atoms accelerated by ionizing irradiation. [ABSTRACT FROM AUTHOR]

The oriental fruit fly is a polyphagous and highly invasive economically important pest in the world. We proposed the hypothesis that radiation treatment influence RNA expression in the larvae and leads to emergence failure. Therefore, transcriptome analyses of third-instar larvae of B. dorsalis ionizing, irradiated with 60Co-γ at 116Gy, were conducted and compared with the controls; a total of 608 DEGs were identified, including 348 up-regulated genes and 260 down-regulated ones. In addition, 130 SNPs in 125 unigenes were identified. For the DEGs, the most significantly enriched GO item was hemolymph coagulation, and some of the enriched pathways were involved in digestive processes. The subsequent validation experiment confirmed the differential expression of six genes, including sqd, ENPEP, Jhe, mth, Notch, and Ugt. Additionally, the 3401:G->A SNP in the Notch gene was also successfully validated. According to previous research, this was the first comparative transcriptome study to discover the candidate genes involved in insect molt to pupae. These results not only deepen our understanding of the emerging mechanism of B. dorsalis but also provide new insights into the research of biomarkers for quarantine insect treatment with the appropriate dose of radiation.

[Display omitted] • 50 Gy of X-ray radiation has health-deteriorating effects on Apis mellifera workers. • 15 Gy irradiation against varroa is the most promising, which affects the bees least. • Apis mellifera immune cell composition changes because of X-ray irradiation. • The higher radiation doses increase plasmatocyte while decrease prohemocyte numbers. Varroa destructor is one of the most destructive enemies of the honey bee, Apis mellifera all around the world. Several control methods are known to control V. destructor , but the efficacy of several alternative control methods remains unexplored. Irradiation can be one of these unknown solutions but before practical application, the effectiveness, and the physiological effects of ionizing radiation on the host and the parasite are waiting to be tested. Therefore, the objective of our study was to investigate the effects of different doses (15, 50, 100, and 150 Gy) of high-energy X-ray irradiation through mortality rates and hemocyte composition changes in A. mellifera workers and record the mortality rates of the parasite. The mortality rate was recorded during short-term (12, 24, and 48 h) and long-term periods (3, 6, 12, 18, and 24d). The sensitivity of the host and the parasite in case of the higher doses of radiation tested (50, 100, and 150 Gy) been demonstrated by total mortality of the host and 90 % of its parasite has been observed on the 18th day after the irradiation. V. destructor showed higher sensitivity (1.52-times higher than the adult honey bee workers) at the lowest dose (15 Gy). A. mellifera hemocytes were influenced significantly by radiation dosage and the elapsed time after treatment. The higher radiation doses increased plasmatocyte numbers in parallel with the decrease in prohemocyte numbers. On the contrary, the numbers of granulocytes and oencoytes increased in the treated samples, but the putative effects of the different dosages on the recorded number of these hemocyte types could not be statistically proven. In summary, based on the outcome of our study X-ray irradiation can be deemed an effective tool for controlling phoretic V. destructor. However, further research is needed to understand the physiological response of the affected organisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fine structure of potato starch mediated with irradiation type was compared. • The digestograms of irradiated starch was fitted by a CPS kinetic model. • Irradiation preferentially destroyed the internal structure of large granules. • Increased double helix structure and semi-crystalline thickness increased RS content. • X-ray at higher doses was more able to damage structure and reduce digestibility. The change of digestibility of starch irradiated with different types from the perspective of fine structure is not well understood. In this work, the change of internal structure, molecular weight and chain-length distribution, helical structure, lamellar structure, fractal structure and digestibility of native and treated potato starch with electron beam and X-ray was analyzed. Two irradiations caused the destruction of internal structure, the disappearance of growth rings and increase of pores. Irradiation degraded starch to produce short chains and to decrease molecular weight. Irradiation increased double helical content and the thickness and peak area of lamellar structure, resulting in the reorganization of amylopectin and increase of structure order degree. The protected glycosidic linkages increased starch resistance to hydrolase attack, thereby enhancing the anti-digestibility of irradiated starch. Pearson correlation matrix also verified the above-mentioned results. Moreover, X-ray more increased the anti-digestibility of starch by enhancing ability to change fine structure. [ABSTRACT FROM AUTHOR]

Purpose: Ionizing radiation therapy (RT) is the main option for head and neck cancer treatment, but it is associated with multiple side effects. This study aimed to evaluate the effect of RT associated with chewing simulation on the surface of human enamel and Yttria-partially stabilized zirconia (Y-TZP). Methods: Maxillary premolar cusps and Y-TZP slabs were divided in 7 experimental groups: CO: no RT (control); EZ groups had irradiation applied to both, enamel and zirconia samples (simulating restoration prior to RT); E groups had irradiation applied to enamel only (simulating restoration after RT). RT doses were either 30, 50 or 70 Gray (Gy). Enamel cusps were abraded against zirconia slabs in a chewing simulator (CS - one million cycles/ 80 N/ 60 mm/min, 2 mm horizontal path, artificial saliva, 37˚ C). Zirconia hardness was evaluated before CS; zirconia roughness and enamel volume (wear) were evaluated before and after CS. Hardness and wear data were analyzed by one-way Analysis of Variance and Tukey post hoc test. Roughness was analyzed by Repeated Measures test and Bonferroni test (p=0.05). Results: There was no significant effect of enamel or zirconia irradiation on enamel cusp wear (p=0.226), regardless of the irradiation dose used - up to 70 Gy. Irradiation also did not affect Y-TZP surface roughness (p=0.127) and hardness (p=0.964). Conclusions: RT does not promote significant changes to the surface characteristics of zirconia. Irradiated enamel abraded against zirconia does not show higher wear volume when compared to non-irradiated enamel. [ABSTRACT FROM AUTHOR]

At the present, the mechanism of chlorophyll degradation in response to ionizing irradiation in harvested fruits have not been examined. To understand the effect of electron beam (E-beam) irradiation on the chlorophyll degrading pathway in relation to chlorophyll degrading enzymes activity, reactive oxygen species (ROS) and antioxidant capacities of harvested mangoes stored at 13 °C for 16 days were studied. E-beam-treated fruit significantly suppressed the activities of chlorophyll degrading enzymes especially pheophytinase (PPH) and chlorophyll degrading peroxidase (Chl-POX) in the late stage of storage. This resulted in the chlorophyll content being maintained. However, E-beam irradiation did not affect the activities of chlorophyllase (Chlase) and magnesium de-chelatase (MD). The respiration rate, ethylene production, ROS accumulation (hydrogen peroxide [H2O2] and superoxide radical [O−.2]) immediately increased after E-beam treatment, following which they significantly decreased in comparison to the control. E-beam treatment enhanced the fruit's antioxidant capacity by activating the activities of catalase (CAT) and ascorbate peroxidase (APX) and glutathione (GSH) content, and inactivated the activity of superoxide dismutase (SOD). Further, it did not affect the activity of glutathione reductase (GR) and glutathione disulfide (GSSG), vitamin C content, or total phenolic content. These results imply that E-beam treatment has the potential to delay chlorophyll degradation by suppressing the Chl-POX and PPH activities as well as reduce ROS production via CAT, APX, and SOD activities and GSH content. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of ionizing irradiation on human enamel and zirconia after chewing simulation. Methods: Twenty enamel and twenty translucent Yttria-stabilized zirconia (Y-PSZ) specimens were divided in 4 groups: Co (control) - no irradiation on enamel cusps/opposing zirconia slabs; E70 - irradiated (70 Gray) enamel cusps/opposing irradiated enamel slabs; Z70 - irradiated zirconia cusps/opposing irradiated zirconia slabs; EZ70 - irradiated enamel cusps/opposing irradiated zirconia slabs. Cusps were abraded against slabs in a chewing simulator (CS - one million cycles, 80 N, artificial saliva, 37°C). Wear and roughness of zirconia and enamel were analyzed using a stylus profilometer. The abraded enamel was analyzed by Electron probe micro-analyzer (EPMA) and zirconia was characterized by nanoindentation and X-ray diffraction. One-way analysis of variance (ANOVA) and Tukey test were used for analysis of wear, Repeated Measures and Bonferroni test for roughness, and hardness and modulus values were compared using Wilcoxan Mann Whitney rank sum test (overall 5% significance). Results: Significantly higher volume loss was presented by cusps in the E70 group (p<0.001). Wear was similar between Co and EZ70 groups. There was no significant effect of irradiation on roughness of enamel or zirconia slabs (p=0.072). Irradiated Y-PSZ slabs had significantly higher hardness and modulus than non-irradiated ones and a 7% increase in m phase content was detected after irradiation. Conclusions: The opposing surface characteristics played a more significant role on enamel wear than did ionizing radiation. However, radiation affects Y-PSZ crystalline composition, hardness and modulus of elasticity. [ABSTRACT FROM AUTHOR]

Effective repair of radiation-induced DNA lesions is an important factor in the radioresistance of plants. Taking into account the role of the DNA mismatch repair (MMR) in the systemic reaction of plants to the action of sublethal doses of ionizing radiation has not yet been sufficiently clear enough. The study of the effect of low LET ionizing radiation in doses up to 21 Gy had been performed, including measurement of the biomass accumulation in Arabidopsis thaliana Atmsh2-/- plants, defective in one of the key components of MMR-repair, MSH2 protein. It has been established that the relative radiosensitivity of Atmsh2 SALK_002708 mutants to the action of sublethal doses of radiation depends on the dose and mode of irradiation. Changes in the radiosensitivity of mutant plants at different doses and due to the fractionation of the dose can be related to the radiation-induced transcriptional response of genes, coding DNA repair proteins, which compensate the lack of MMR-repair or along with MSH2 participate in the mutagenic pathways of DNA repair.

Effectiveness of the use of Ampullaria glauca snails caviar for correction of radiation-induced disturbances after external disposable γ-irradiation of rats in dose of 2.0 Gy was investigated. Under these experimental conditions membrane stabilizing and adaptogenic properties of snails caviar have been established. Also, in rats that were irradiated at 2.0 Gy and consumed caviar of snails, normalization of the functional state of thyroid, pancreas and adrenal glands were revealed. Application of Ampullaria glauca snail caviar leads to modification of radiation damage and can be used to correct radiogenic disturbances in organism that is irradiated in small doses.

Sodium selenite is often given to moderate the side effects of cancer therapy to enhance the cellular defence of non-cancerous cells. To determine whether sodium selenite during radiotherapy protects not only normal cells but also cancer cells, which would imply a reduction of the desired effect of irradiation on tumour during radiotherapy, the effect of the combined treatment of irradiation and sodium selenite was investigated. Human bronchial cells from carcinoma (A549) and normal tissue (BEAS-2B) were treated with sodium selenite and effects on growth and in combination with radiation on metabolic activity and cell cycle distribution were studied. The influence on radiosensitivity was determined via colony forming assays using different solvents of sodium selenite and treatment schedules. It was shown that sodium selenite inhibits growth and influences cell cycle distribution of both normal and tumour cells. Metabolic activity of normal cells decreased more rapidly compared to that of cancer cells. The influence of sodium selenite on radiation response depended on the different treatment schedules and was strongly affected by the solvent of the agent. It could be shown that the effect of sodium selenite on radiation response is strongly dependent on the respective experimental in vitro conditions and ranges from lead to an initially suspected but ultimately no real radioprotection to radiosensitizing up to no effect in one and the same cell line. This might be a reason for controversially described cell responses to radiation under the influence of sodium selenite in studies so far. [ABSTRACT FROM AUTHOR]

A new quantitative model of the effect of the gate bias on the threshold voltage of metal-oxide-semiconductor (MOS) structures under ionizing irradiation is developed based on the consideration of hole trapping from the entire volume of the gate dielectric in a thin boundary layer with hydrogen-free and hydrogen-containing traps at the interface with a silicon substrate. The model makes it possible to adequately describe a gradual increase in the threshold voltage with gate bias as approximately linear with dose for the surface component and nonlinear for the bulk component. The threshold-voltage shift at negative gate bias is simulated based on hole generation in the boundary layer under ionizing irradiation. [ABSTRACT FROM AUTHOR]

Processing of food products by ionizing radiation that has been used for more than 20 years in various countries, has been legally permitted in Russia since 2017. Investigations of domestic and foreign scientists have proved the suitability of this treatment method for the purpose of sterilizing various types of products. The authors consider data on the effect of ionizing radiation on consumer properties of products to be insufficient. Sensory properties of minced poultry meat with the addition of plant powders subjected to irradiation with doses of varying power have been assessed. The results of the studies have shown significant changes in the organoleptic properties of a product when irradiated at 30 kGy and the possibility of maintaining sensory properties when irradiated with a dose of 12 kGy. The results of the research have determined the direction of further research on consumer properties, namely, nutritional value and safety of products exposed to a dose of 12 kGy.

The present work studied, for the first time, the effect of two technologies on the hydration and germination process of beans: ionizing irradiation and ultrasound. In addition, this work proposed a possible biological effect of ultrasound to describe its effect on grain hydration. Carioca beans were irradiated at doses of 2.3 and 3.8 kGy using γ‐rays, establishing different metabolic activities for the beans. Then, they were hydrated with and without the ultrasound technology (91 W/L and 25 kHz) at 25 °C. Both the hydration and germination kinetics were evaluated considering the application of both technologies alone and in combination. As results, irradiation did not significantly affect (P > 0.05) the hydration rate, the equilibrium moisture, or the lag phase time, but ultrasound affected them, reducing 50% of the processing time. On the other hand, only the equilibrium moisture was slightly reduced by the interactive effect of irradiation and ultrasound technology, which was discussed based on different metabolism levels. Furthermore, the germination process of carioca bean was hindered by both the studied variables, reducing its germination capacity to 0% in some cases. Therefore, by studying the effect of ultrasound on beans with different active metabolism (due to different irradiation doses), it was suggested that both physical and biological mechanisms are involved during hydration process and that both can be affected by ultrasound. Further, irradiation could be used on carioca beans with objectives such as avoid germination, insects, and microorganism's growth, without an important effect on the hydration kinetics. Practical Application: Ultrasound technology has demonstrated to accelerate the soaking process of several legume grains. However, sometimes, grains are irradiated for disinfestation purpose to improve their shelf life. Indeed, irradiation can change the grain properties as the cooking time, hydration time, and germination capacity. Therefore, this work verified if irradiation changes the desirable effect of ultrasound on grain processing: soaking and germination. Moreover, this work novelty is also based on describing the phenomena: by proposing a possible biological effect, further approaches to improve the grain processing can be achieved. [ABSTRACT FROM AUTHOR]

Prenatal brain development is a complex and sensitive process, highly susceptible to environmental influences such as pollutants, stress, malnutrition, drugs, tobacco exposure, or ionizing radiation (IR). Disturbances in development may cause life-long disabilities and diseases, such as ADHD, childhood cancers, cognitive problems, depression, anxiety and more severe developmental disabilities. Due to increasing medical imaging, radiation therapy, natural terrestrial radiation, radioactive pollution and long-distance flights, humans are increasingly exposed to IR. However, data on impact of IR on very early human brain development are scarce, particularly in the very first weeks of gestation. Here we investigated the effects of low-dose X-ray IR (1 Gy) in a 3D early brain developmental model derived from human pluripotent stem cells. In this model very early neural stem cells, neuroectodermal progenitor cells (NEP), were exposed to low-dose IR and direct as well as delayed effects were investigated. Expression of 20 different marker genes crucial for normal neural development was determined 48 h and 9 days post IR (pIR). All but one of the analyzed marker genes were reduced 48 h after IR, and all but seven genes normalized their expression by day 9 pIR. Among the seven markers were genes involved in neurodevelopmental and growth abnormalities. Moreover, we could show that stemness of the NEP was reduced after IR. We were thus able to identify a significant impact of radiation in cells surviving low-dose IR, suggesting that low-dose IR could have a negative impact on the early developing human brain, with potential later detrimental effects. [ABSTRACT FROM AUTHOR]

This article provides a general overview of the results of research on the influence of the reaction media and various types of electromagnetic radiation on the polymerization of inorganic monomers, carried out during the last decade at UNESCO Chair in Green Chemistry for Sustainable Development of Dmitry Mendeleev University of Chemical Technology of Russia. [ABSTRACT FROM AUTHOR]

Sulfonamide (SA) is an emerging contaminants and the efficient treatment of SA containing wastewater remains a challenge. Herein, SA degradation by gamma irradiation has been systematacially studied. SA (10 mg/L) could be totally removed with 1.5 kGy irradiation. Quenching experiments demonstrated that •OH and e aq − were the predominant for SA degradation. SA degradation was reduced with initial concentration increasing, and the removal was faster with pH increasing in the range of 3.1–10.8. The coexisting matters affected SA degradation through changing reactive species, and the introduction of SO 4 2− and Cl− enhanced SA degradation, while CO 3 2− had a negative impact on SA degradation, and the degradation was insignificantly affected when adding humic acid. Gamma irradiation could remain effective in real water matrixes. In conjunction with LC-MS analysis and DFT calculation, possible degradation pathways for SA were proposed. Gamma irradiation could reduce the toxicity of SA, while several byproducts with more toxic were also formed. Furthermore, gamma/priodate (PI) process was promising to enhance SA degradation and mineralization. k value increased by 1.85 times, and mineralization rate increased from 19.51% to 79.19% when adding PI. This study suggested that ionizing radiation was efficient to eliminate SA in wastewater. [Display omitted] • Ionizing irradiation was efficient for sulfanilamide degradation. • •OH and e aq − were the predominant in degradation by gamma irradiation. • Degradation pathways for sulfanilamide were proposed. • Periodate could improve sulfanilamide degradation by gamma irradiation. [ABSTRACT FROM AUTHOR]

Combination therapy with immune checkpoint blockade and ionizing irradiation therapy (IR) generates a synergistic effect to inhibit tumor growth better than either therapy does alone. We modeled the tumor-immune interactions occurring during combined IT and IR based on the published data from Deng et al. The mathematical model considered programmed cell death protein 1 and programmed death ligand 1, to quantify data fitting and global sensitivity of critical parameters. Fitting of data from control, IR and IT samples was conducted to verify the synergistic effect of a combination therapy consisting of IR and IT. Our approach using the model showed that an increase in the expression level of PD-1 and PD-L1 was proportional to tumor growth before therapy, but not after initiating therapy. The high expression level of PD-L1 in T cells may inhibit IT efficacy. After combination therapy begins, the tumor size was also influenced by the ratio of PD-1 to PD-L1. These results highlight that the ratio of PD-1 to PD-L1 in T cells could be considered in combination therapy.

The MYCN oncogene is amplified in 20% of neuroblastomas, leading to its overexpression at both the mRNA and protein levels. MYCN overexpression is strongly associated with advanced disease stage, rapid tumor progression and a worse prognosis. In the present study, we identified microRNA‐375 (miR‐375) as a negative regulator of MYCN: enforced expression of miR‐375 inhibited MYCN‐amplified neuroblastoma in vitro and in vivo. Upon searching the website miRbase for possible miR‐375 binding sites within the whole MYCN mRNA, we found that the MYCN 5′‐UTR had significant sequence complementarity to miR‐375, yet no complementary sequences existed within the MYCN 3′‐UTR and coding regions. Enforced overexpression of miR‐375 efficiently inhibited MYCN mRNA translation and protein synthesis, via an IRES‐dependent mechanism. In athymic nude mouse model with human MYCN‐amplified neuroblastoma, MYCN downregulation by miR‐375 led to inhibition of tumor cell growth and tumorigenicity. In particular, miR‐375‐regulated inhibition of MYCN translation was enhanced when MYCN‐amplified neuroblastoma cells were exposed to stress stimulation, such as ionizing irradiation (IR), resulting in a remarkable increase in the neuroblastoma's sensitivity to IR‐induced cell death. Our results identified a novel mechanism by which IRES‐dependent translation of MYCN is repressed by miR‐375, particularly during cellular stress, highlighting a potential anticancer strategy: the development of miR‐375 as a novel therapeutic agent to treat MYCN‐amplified neuroblastoma.

Ionizing irradiation induces acute and chronic injury to tissues and organs. Applications of antioxidant therapies for the management of ionizing irradiation injury fall into three categories: (1) radiation counter measures against total or partial body irradiation; (2) normal tissue protection against acute organ specific ionizing irradiation injury; and (3) prevention of chronic/late radiation tissue and organ injury. The development of antioxidant therapies to ameliorate ionizing irradiation injury began with initial studies on gene therapy using Manganese Superoxide Dismutase (MnSOD) transgene approaches and evolved into applications of small molecule radiation protectors and mitigators. The understanding of the multiple steps in ionizing radiation-induced cellular, tissue, and organ injury, as well as total body effects is required to optimize the use of antioxidant therapies, and to sequence such approaches with targeted therapies for the multiple steps in the irradiation damage response.

Microalgae have been drawing much attention as a platform for food supplements and biofuel production. Advance molecular tools are not available for manipulating microalgae, and therefore, methods for strain improvement mostly depend on random mutation. Radiation is frequently used mutagen in plant as well as microalgae breeding methods. In this study, the resistance of 7 microalgae species to ionizing irradiation was measured. To monitor the growth of microalgae, optical density and staining methods were used. Based on the D10 values, the dose required to reduce one log cycle of the cell population, Chlorella protothecoides, Zygnema circumcarinatum, and Spirogyra varians were shown to be highly resistant to ionizing radiation. The changes in protein expression levels in S. varians were further investigated. Using 2-dimensional electrophoresis and protein identification, it was shown that some proteins involved in energy and glyceride metabolisms were up-regulated. These results provide fundamental insights into metabolic changes that occur in a microalga species upon exposure to ionizing irradiation. [ABSTRACT FROM AUTHOR]

Effective repair of radiation-induced DNA lesions is an important factor in the radioresistance of plants. Taking into account the role of the DNA mismatch repair (MMR) in the systemic reaction of plants to the action of sublethal doses of ionizing radiation has not yet been sufficiently clear enough. The study of the effect of low LET ionizing radiation in doses up to 21 Gy had been performed, including measurement of the biomass accumulation in Arabidopsis thaliana Atmsh2-/- plants, defective in one of the key components of MMR-repair, MSH2 protein. It has been established that the relative radiosensitivity of Atmsh2 SALK_002708 mutants to the action of sublethal doses of radiation depends on the dose and mode of irradiation. Changes in the radiosensitivity of mutant plants at different doses and due to the fractionation of the dose can be related to the radiation-induced transcriptional response of genes, coding DNA repair proteins, which compensate the lack of MMR-repair or along with MSH2 participate in the mutagenic pathways of DNA repair. [ABSTRACT FROM AUTHOR]

Effectiveness of the use of Ampullaria glauca snails caviar for correction of radiation-induced disturbances after external disposable γ-irradiation of rats in dose of 2.0 Gy was investigated. Under these experimental conditions membrane stabilizing and adaptogenic properties of snails caviar have been established. Also, in rats that were irradiated at 2.0 Gy and consumed caviar of snails, normalization of the functional state of thyroid, pancreas and adrenal glands were revealed. Application of Ampullaria glauca snail caviar leads to modification of radiation damage and can be used to correct radiogenic disturbances in organism that is irradiated in small doses. [ABSTRACT FROM AUTHOR]

Abstract. In the present study, blood levels of circulating immune complexes and of their pathogenic subpopulations were determined in rats following ionizing irradiation. Experimental animals were treated with synthetic Schiff base aromatic amino acid derivatives, nicotinyl-L-tyrosinate or nicotinyl-L-tryptophanate, before irradiation, whereas untreated irradiated rats served as controls. The results obtained demonstrate significantly increased levels of immune complexes, as well as presence of a pathogenic subpopulation of circulating immune complexes in blood of irradiated animals. In addition, the data obtained suggest a normalizing effect of nicotinyl-L-tyrosinate and nicotinyl-L-tryptophanate upon the mentioned parameters. On the basis of these observations, a cyto- and immunoprotective ability of nicotinyl-L-tyrosinate and nicotinyl-L-tryptophanate may be proposed.

The radiation-induced effects at dose rate of 0.35 Gy/min (in vivo) and of ultra-low doses (in vitro) on the cell membranes structural state were shown. The modifications of the membrane protein and lipid components and their dynamic state were revealed at experimental irradiation conditions by fluorescent probe analysis. The principal component analysis of the research data indicates the dose-dependent decrease of plasma membrane structural orderliness of the small intestine enterocytes with the increase of the ionizing irradiation acute dose of 0.5, 1.0, 2.0, 3.0 Gy at dose rate of 0.35 Gy/min. The complex response of the biological structure – the erythrocytes plasma membrane, on the ionizing radiation action at ultra-low doses that occurred through macromolecular structural rearrangements was also demonstrated. The features of the structural rearrangement of the cellular membranes depending on the ionizing radiation dose (dose rate) are found out.

Microglia remove apoptotic cells by phagocytosis when the central nervous system is injured in vertebrates. Ionizing irradiation (IR) induces apoptosis and microglial activation in embryonic midbrain of medaka (Oryzias latipes), where apolipoprotein E (ApoE) is upregulated in the later phase of activation of microglia In this study, we found that another microglial marker, L-plastin (lymphocyte cytosolic protein 1), was upregulated at the initial phase of the IR-induced phagocytosis when activated microglia changed their morphology and increased motility to migrate. We further conducted targeted irradiation to the embryonic midbrain using a collimated microbeam of carbon ions (250 μm diameter) and found that the L-plastin upregulation was induced only in the microglia located in the irradiated area. Then, the activated microglia might migrate outside of the irradiated area and spread through over the embryonic brain, expressing ApoE and with activated morphology, for longer than 3 days after the irradiation. These findings suggest that L-plastin and ApoE can be the biomarkers of the activated microglia in the initial and later phase, respectively, in the medaka embryonic brain and that the abscopal and persisted activation of microglia by IR irradiation could be a cause of the abscopal and/or adverse effects following irradiation. [ABSTRACT FROM AUTHOR]

Phytosanitary treatments prevent the introduction of pests such as fruit flies into pest free zones, and are often required for international trade. Irradiation is increasingly being considered as an alternative to cold and chemical phytosanitary treatments, such as methyl bromide. In this study, the effect of low dose gamma irradiation on the post-harvest quality of two varieties of pummelos ( Citrus maxima (Burm.) Merr.), an emerging crop of interest in the US was evaluated. Two varieties of pummelos grown in California were irradiated at the phytosanitary target dose of 150 Gy and a higher dose of 1000 Gy to exaggerate and hence confirm the effects of treatment. The fruit was stored at 12 °C for 3 weeks and at 20 °C for the 4th week to reflect three weeks of sea shipment at the ideal temperature for storage of pummelos and an additional week of retail under ambient conditions. Neither irradiation nor storage affected juice content, organic acids, sugars, peel or pulp color and consumer sensory preference, although numerous volatiles increased in concentration as a result of irradiation treatment. Irradiation caused an immediate reduction in whole fruit and pulp firmness in ‘Chandler’ but not ‘Sarawak’ pummelos at both 150 Gy and 1000 Gy. The quality of irradiated pummelos stored at refrigerated temperature for 3 weeks was similar to untreated pummelos, however, physical handling and exposure to higher temperature resulted in increased peel pitting of irradiated fruit compared to non-treated fruit. The results suggest that irradiation could serve as a potential phytosanitary treatment for Chandler and Sarawak pummelos, provided that the fruit is subjected to minimal handling and not temperature abused. [ABSTRACT FROM AUTHOR]

Activated carbon (AC) has been widely used for reclamation and reuse of the effluent of wastewater treatment plant to further remove the emerging contaminants, such as PPCPs in recent years. How to regenerate the exhausted AC effectively and economically is still a challenge. In the present study, the regeneration of AC exhausted with SMX was performed by gamma irradiation to simultaneously recover the spent AC and degrade the pollutants. The results showed that the adsorption of SMX onto AC can be described by the Langmuir isotherm and the adsorption capacity was about 417 mg/g. SMX can be removed rapidly when exposed to gamma irradiation, with the initial concentration of 100 mg/L, more than 99% of SMX was removed at 5.0 kGy, while an extremely high dose (150 kGy) was needed to reach 80% mineralization ratio. The regeneration efficiency was about 21–30% at 50–200 kGy. The absorbed SMX and the intermediates formed during gamma irradiation were released into aqueous solution from AC and mineralized, leading to the partial regeneration of the adsorption capacity of AC. Further studies are needed to optimize the experimental conditions to increase the regeneration efficiency. [ABSTRACT FROM AUTHOR]

• Radiolytic changes in terrestrial OM are predominately caused by γ-radiation. • In situ radiolysis of oil provides a potential chronometer for oil residence time. • Radiation interplays with thermal force and may boost hydrocarbon generation. • OM radiolysis is an alternative explanation for abnormal natural gas signatures. • Radiolysis of sedimentary OM is more complex than previously thought. Ionizing radiation of organic matter (OM) is ubiquitous on the surface and in the subsurface of rocky planets such as Earth and Mars, and is associated with chemical changes in the elemental, isotopic, bulk and molecular compositions of OM over geological time scales. Plentiful efforts have been made in the last decade that contribute to growing understanding of subsurface OM irradiation and insights into perplexing petroleum system dynamics worldwide. This review opens with a brief introduction of recent progress in the technical application of OM radiolysis in multiple scientific areas to elucidate basic radiolysis principles that also govern both artificial and natural irradiation of OM. In light of these considerations, four major topics covering radiolysis in geological systems are addressed: (1) radiation of kerogen in radioactive shales and changes in OM chemical compositions, (2) radiolytic alteration of crude oil and its potential application in tracing oil residence time, (3) characteristics of radiolytic natural gases and geochemical templates for distinguishing natural gases of various origins, and (4) radiolytic synthesis of simple precursors into larger OM molecules. Highlights are the exploration of proxies using radiolytic changes in OM as geochronometers for oil residence time dating under topic (2), and the novel interpretation of obscured natural gas formations worldwide based on the newly proposed geochemical template for natural gas origins under topic (3). This review wraps up with a brief discussion of the radiation environment on Mars and an analogy between Mars and Earth, which bears valuable information on the preservation of OM on both planets in response to irradiation and may shed light on the origin of life and evidence for life on extraterrestrial planets. [ABSTRACT FROM AUTHOR]

Electron beam (particle radiation) and X-ray (electromagnetic radiation) without radioisotope in the application of material modification have received increasing attention in the last decade. To clarify the effect of electron beam and X-ray on the morphology, crystalline structure and functional properties of starch, potato starch was irradiated using electron beam and X-ray at 2, 5, 10, 20 and 30 kGy, respectively. Electron beam and X-ray treatment increased the amylose content of starch. The surface morphology of starch did not change at lower doses (< 5 kGy), but starch granules were aggregated with the increase of doses. All treatments decreased crystallinity, viscosity and swelling power but increased solubility and stability properties. The effects of electron beam and X-ray on the starch had a similar trend. Unlike X-ray, electron beam destructed the crystallinity of starch to a lesser extent, thereby increasing thermal stability and freeze-thaw stability. Furthermore, X-ray irradiation at higher doses (> 10 kGy) resulted in outstanding anti-retrogradation properties of starch compared with electron beam treatment. Thus, particle and electromagnetic irradiation displayed an excellent ability to modify starch with respective specific characteristics, which expands the potential application of these irradiations in the starch industry. • X-ray, low risk-significant radioactive source, was applied to modifying starch. • Effects of two irradiation types on the properties of starch were compared. • Starch irradiated by electron beam has higher stability. • X-ray at higher doses (>5 kGy) enhanced the anti-retrograde of starch even more. [ABSTRACT FROM AUTHOR]