scholarly journals The influence of electron and gamma irradiation on the properties of starch:PVA films – the effect of irradiation dose

Nukleonika ◽  
2021 ◽  
Vol 66 (1) ◽  
pp. 3-9
Author(s):  
Krystyna A. Cieśla ◽  
Anna Abramowska
Keyword(s):  
Ionizing Radiation ◽  
Gamma Rays ◽  
Irradiation Dose ◽  
Radiation Treatment ◽  
Weight Ratio ◽  
Solution Casting ◽  
Solubility In Water ◽  
Fast Electrons ◽  
Essential Change ◽  
Specific Reactions

Abstract The paper discusses the effect of ionizing radiation on the functional properties of the biodegradable starch:PVA films. The analysis is related to the possible use of the material for packing the products (particularly, food) that are predicted for radiation decontamination and to the potential modification of the material by radiation treatment. Our previous results have shown that the influence of ionizing radiation on the films’ properties varied for the specific compositions (differing in starch:PVA ratio or the type of substrates) and depended on irradiation conditions. However, these studies considered only the irradiation performed in gamma chamber or in e-beam using a dose of 25 kGy. Therefore, the present study deals with the effect of the irradiations performed using various doses on the selected promising starch:PVA composition. The films characterized by starch:PVA weight ratio of 45:55 was obtained by solution casting and irradiated with fast electrons in air and with 60Co gamma rays in nitrogen applying the doses of 5, 10, 20, 25, 30, 50, and 75 kGy. No regular dependence has been noticed between the composition of films (differing in the starch and PVA content) and the intensities of the particular bands in the UV-VIS DRS spectra after irradiation. The results indicated strong interaction of the starch and PVA components in the films and the occurrence of specific reactions in each composition upon irradiation. No special differences were observed between tensile strength and Young’s modulus of the non-irradiated films characterized by the starch:PVA ratio equal to 45:55 and the samples irradiated using doses in the range of 5–75 kGy. Similarly, no differences were observed in both cases between the swelling capability of the non-irradiated and the irradiated films. However, it can be deduced that solubility in water increased when the radiation dose increased. The results show that using the doses till the range 25 kGy does not cause an essential change of all the examined properties of the starch:PVA (45:55) films. Accordingly, starch:PVA (45:55) films might be considered suitable for packing food predicted for radiation decontamination.

scholarly journals The influence of ionizing radiation on the properties of starch-PVA films

Nukleonika ◽  
2015 ◽  
Vol 60 (3) ◽  
pp. 669-677 ◽  
Author(s):  
Anna Abramowska ◽  
Krystyna A. Cieśla ◽  
Marek J. Buczkowski ◽  
Andrzej Nowicki ◽  
Wojciech Głuszewski
Keyword(s):  
Tensile Strength ◽  
Gamma Rays ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Absorbed Dose ◽  
Oxidation Products ◽  
Strong Interactions ◽  
Poly Vinyl Alcohol ◽  
Solution Casting ◽  
Fast Electrons

Abstract The cornstarch: poly(vinyl alcohol) (PVA) films characterized by the alternating ratio of starch:PVA (100:0, 80:20, 60:40, 40:60, 20:80, and 0:100) and containing 30% of glycerol were prepared by solution casting. The films were irradiated with an absorbed dose of 25 kGy with gamma rays in a vacuum and with fast electrons in the air. The films characterized by a high content of starch appeared stiff, while the films characterized by a high content of PVA were highly flexible. The tensile strength and flexibility, as well as swelling and hydrophilicity, increased with the increase in the PVA content in the films. However, the tensile strength and wetting angle values achieved a minimum at an intermediate composition. It was found that irradiation enables to reduce hydrophilicity of the films accompanied by a decrease in their flexibility. No general conclusion concerning the effect of irradiation on tensile strength and swelling behavior can be derived. An increase in the homogeneity of the films and an increase in the compatibility of their components was found by scanning electron microscopy (SEM). Strong interactions of the starch and the PVA components were discovered by diffuse reflectance spectroscopy. Degradation was found to be the prevailing process occurring in the films under the influence of irradiation. The possible accompanying crosslinking is discussed in terms of the gel content in the samples. Creation of various oxidation products in the films characterized by the modified composition was observed under the influence of irradiation carried out in the air. Basing on the obtained results it can be supposed that the selected starch-PVA compositions might appear useful as packagings of the products predicted for radiation decontamination.

COMPACT MUTANTS OF APPLE INDUCED BY IONIZING RADIATION

1965 ◽  
Vol 45 (2) ◽  
pp. 117-124 ◽  
Author(s):  
K. Lapins
Keyword(s):  
Ionizing Radiation ◽  
Gamma Rays ◽  
Growth Habit ◽  
Radiation Treatment ◽  
Tree Size ◽  
Growth Reduction ◽  
Apple Varieties ◽  
Acute Irradiation ◽  
Compact Growth ◽  
Leaf Mutants

Mutations of compact habit of growth were induced in selected apple varieties by acute irradiation with gamma rays from a Co60 source at doses ranging from 3750 rad to 7500 rad. The rate of mutation was high. In trees of the McIntosh variety, repropagated from irradiated material, the percentage of total vegetative (tree or leaf) mutants was 9.8 and the percentage of compact mutants 5.2. The compact mutants were characterized by shortened internodes and reduced tree size. Various degrees of growth reduction were induced by the radiation treatment. Most of the compact mutants produced fruit of an undesirable shape, often flattened, irregular, and grooved. However, mutants were selected which combined the desirable compact growth habit with fruit that was characteristic of the variety.

SKIN MELANOMA INCIDENCE IN WORKERS OCUPATIONALLY EXPOSED TO IONIZING RADIATION OVER A PROLONGED PERIOD

2019 ◽  
Vol 65 (3) ◽  
pp. 441-446
Author(s):  
Valentina Rybkina ◽  
Tamara Azizova ◽  
Yevgeniya Grigoreva
Keyword(s):  
Ionizing Radiation ◽  
Gamma Rays ◽  
Disease Risk ◽  
Incidence Rates ◽  
Study Cohort ◽  
Calendar Period ◽  
Skin Melanoma ◽  
Melanoma Incidence ◽  
Occupationally Exposed

Purpose of the study. The study is aimed to investigate skin melanoma incidence in workers occupationally exposed to radiation over a prolonged period. Materials and methods. Skin melanoma incidence was studied in a cohort of workers first employed at nuclear facility Mayak Production Association (PA) between 1948 and 1982 who had been followed up till 31.12.2013 (22,377 individuals). Mean cumulative doses from external gamma-rays over the whole follow-up period were 0.54±0.001 Sv in males and 0.44±0.002 Sv in females. Incident rates for skin melanoma were analyzed by sex, attained age, calendar period of diagnostics and radiation dose using worldwide standard and the direct standardization technique. Results. 60 skin melanoma cases (37 in males and 23 in females) were registered in the study cohort over the whole follow-up period. The standardized skin melanoma incident rate was 8.51±1.46 in males and 8.78±2.27 in females per 100000 workers revealing statistically higher rates compared to corresponding rates for general populations of the Russian Federation, Urals Federal District and Chelyabinsk region. Skin melanoma incidence was significantly increased in the period of 1994 - 2013 as compared to the period of 1974 - 1993. Skin melanoma incidence excess in females was greater than that for males. Skin melanoma incidence increment in females was mostly driven by modifications of disease occurrence risk while in males it was driven by a combined effect of age pattern modifications in the study cohort and increase of disease risk. Conclusions. Skin melanoma incidence rates in the cohort of workers occupationally exposed to ionizing radiation over a prolonged period were associated with sex and attained age workers and the calendar period of diagnostics. No significant association of skin melanoma incidence with dose from external gamma-rays was observed. A significantly increasing trend was observed for skin melanoma incidence by the end of the follow-up in both males and females.

scholarly journals Differential response of human glioblastoma cell lines to combined camptothecin and ionizing radiation treatment

2008 ◽  
Vol 7 (3) ◽  
pp. 364-373 ◽  
Author(s):  
Cholpon S. Djuzenova ◽  
Teresa Güttler ◽  
Sabrina Berger ◽  
Astrid Katzer ◽  
Michael Flentje
Keyword(s):  
Ionizing Radiation ◽  
Cell Lines ◽  
Radiation Treatment ◽  
Differential Response ◽  
Glioblastoma Cell ◽  
Human Glioblastoma ◽  
Human Glioblastoma Cell ◽  
Glioblastoma Cell Lines

HEALTH HAZARDS FROM MOBILE TOWER: A REVIEW

2021 ◽  
pp. 78-79
Author(s):  
Avni KP Skandhan ◽  
Skandhan KP ◽  
Prasad BS
Keyword(s):  
Ionizing Radiation ◽  
Ultraviolet Radiation ◽  
Visible Light ◽  
Mobile Phone ◽  
Gamma Rays ◽  
Health Hazards ◽  
X Rays ◽  
Radio Waves ◽  
Fm Radio ◽  
Smart Tv

Our knowledge on X-rays, gamma rays and ultraviolet radiation is ionising . Non-ionising gadget radiation is from Mobile Phone, Laptop, Tablet Smart TV etc. and harmful radiations is from mobile towers . FM radio waves, Microwaves, Visible light are also other forms of non-ionizing radiation.

scholarly journals Ionizing radiation effects on food vitamins: a review

2009 ◽  
Vol 52 (5) ◽  
pp. 1267-1278 ◽  
Author(s):  
Ana Paula Dionísio ◽  
Renata Takassugui Gomes ◽  
Marília Oetterer
Keyword(s):  
Chemical Composition ◽  
Ionizing Radiation ◽  
Food Processing ◽  
Irradiation Dose ◽  
Radiation Effects ◽  
Nutritional Value ◽  
Food Composition ◽  
Industrial Processes ◽  
Cosmetic Products ◽  
Irradiation Process

Ionizing radiation has been widely used in industrial processes, especially in the sterilization of medicals, pharmaceuticals, cosmetic products, and in food processing. Similar to other techniques of food processing, irradiation can induce certain alterations that can modify both the chemical composition and the nutritional value of foods. These changes depend on the food composition, the irradiation dose and factors such as temperature and presence or absence of oxygen in the irradiating environment. The sensitivity of vitamins to radiation is unpredictable and food vitamin losses during the irradiation are often substantial. The aim of this study was to discuss retention or loss of vitamins in several food products submitted to an irradiation process.

scholarly journals Study on the immuno stimulation of radiation degraded β-glucan in swiss mice

2015 ◽  
Vol 5 (4) ◽  
pp. 9-15
Author(s):  
Thanh Long Nguyen ◽  
Quang Luan Le
Keyword(s):  
Cell Wall ◽  
Immune System ◽  
Gamma Irradiation ◽  
Gamma Rays ◽  
Irradiation Dose ◽  
Functional Foods ◽  
Water Soluble ◽  
Molecular Weights ◽  
Swiss Mice ◽  
Stimulation Of

The mixtures β-glucan extracted from the yeast cell wall were irradiated under gamma rays from a Co-60 source at doses of 100, 200 and 300 kGy in order to prepare water-soluble β-glucan. Yields of the water soluble β-glucan produced are 25.9, 49.1, 66.71%, and their molecular weights (Mw) are 30.5, 24.9 and 10.8 kDa, respectively. There are no any new peak in the IR spectra of the irradiated β-glucan samples, but the intensity ratio between the peaks at wavenumber of 1156 cm-1 (assigned to C-O-C bond) and of 1040 cm-1 (assigned to C-C bond) in glycosidic linkages was reduced with irradiation dose. These results revealed that gamma irradiation did not cause any change in the β-glucan structure except the scissions of glycosidic linkages. In this study, immuno stimulation of the irradiated b-glucan was also investigated for the Swiss mice. After 28 days supplying with the irradiated b-glucan, not only cellular indexes (white blood cell, neutrophils and lymphocytes counts), but also humoral  immunity indexes (IgA and IgM) of the mice significantly increased and the highest effects was obtained for the mice supplied with the oligoβ-glucan prepared by gamma irradiation at 200 kGy. Thus, the water soluble oligoβ-glucan with Mw ~ 24.9 kDa prepared by gamma radiation much stimulated the natural immune system (non-specific immunity) in mice including both the cellular and humoral immunities. Particularly, the irradiated b-glucan is a very promising product for preparation of functional foods aiming at cancer prevention.

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