The nuclear fuel that melted during the Fukushima nuclear accident in 2011 is still being cooled by water. In this process, contaminated water containing radioactive substances such as cesium and strontium is generated. The total amount of radioactive pollutants released by the natural environment due to the nuclear accident in Fukushima in 2011 is estimated to be 900 PBq, of which 10 to 37 PBq for cesium. Radioactive cesium (137Cs) is a potassium analog that exists in the water in the form of cations with similar daytime behavior and a small hydration radius and is recognized as a radioactive nuclide that has the greatest impact on the environment due to its long half-life (about 30 years), high solubility and diffusion coefficient, and gamma-ray emission. In this study, alginate beads were designed using Prussian blue, known as a material that selectively adsorbs cesium for removal and detection of cesium. To confirm the adsorption performance of the produced Prussian blue, immersion experiments were conducted using Cs standard solution, and MCNP simulations were performed by modeling 1L reservoir to conduct experiments using radioactive Cs in the future. An adsorption experiment was conducted with water containing standard cesium solution using alginate beads impregnated with Prussian blue. The adsorption experiment tested how much cesium of the same concentration was adsorbed over time. As a result, it was found that Prussian blue beads removed about 80% of cesium within 10-15 minutes. In addition, MCNP simulation was performed using a 1 L reservoir and a 3inch NaI detector to optimize the amount of Prussian blue. The results of comparing the efficiency according to the Prussian volume was shown. It showed that our designed system holds great promise for the cleanup and detection of radioactive cesium contaminated seawater around nuclear plants and/or after nuclear accidents. Thus, this work is expected to provide insights into the fundamental MCNP simulation based optimization of Prussian blue for cesium removal and this work based MCNP simulation will pave the way for various practical applications.

There are analytical methods used for measuring activity when light photons are emitted for scintillating-based analytical application. When this electron returns to the original stable state, it releases its energy in the form of light emission (visible light or ultraviolet light), and this phenomenon is called scintillation. Scintillator is a general term for substances that emit fluorescence when exposed to radiation such as gamma-rays. Radioactivity is all around us and is unavoidable because of the ubiquitous existence of background radiations emitted by different sources. The scintillator contributes to these sensing, and it is expected that the inspection accuracy and limit of detection will be improved and new inspection methods will be developed in the future. Moreover, scintillators are chemical or nanomaterial sensors that can be used to detect the presence of chemical species and elements or monitor physical parameters on the nanoscale. In this study, it includes finding use in scintillating-based analytical sensing applications. A chemical and nanomaterial based sensors are self-contained analytical tools that could provide information about the chemical compositions or elements of their environment, that is, a liquid or even gas condition. Herein, we present an insightful review of previously reported research in the development of high-performance gamma scintillators. The major performance-limiting factors of scintillation are summed up here. Moreover, the 2D material has been discussed in the context of these parameters. It will help in designing a prototype nanomaterial based scintillators for radiation detection of gamma-ray.

Radioactive contamination distribution in nuclear facilities is typically measured and analyzed using radiation sensors. Since generally used detection sensors have relatively high efficiency, it is difficult to apply them to a high radiation field. Therefore, shielding/collimators and small size detectors are typically used. Nevertheless, problems of pulse accumulation and dead time still remain. This can cause measurement errors and distort the energy spectrum. In this study, this problem was confirmed through experiments, and signal pile-up and dead time correction studies were performed. A detection system combining a GAGG sensor and SiPM with a size of 10 mm × 10 mm × 10 mm was used, and GAGG radiation characteristics were evaluated for each radiation dose (0.001~57 mSv/h). As a result, efficiency increased as the dose increased, but the energy spectrum tended to shift to the left. At a radiation dose intensity of 400 Ci (14.8 TBq), a collimator was additionally installed, but efficiency decreased and the spectrum was distorted. It was analyzed that signal loss occurred when more than 1 million particles were incident on the detector. In this high-radioactivity area, quantitative analysis is likely to be difficult due to spectral distortion, and this needs to be supplemented through a correction algorithm. In recent research cases, the development of correction algorithms using MCNP and AI is being actively carried out around the world, and more than 98% of the signals have been corrected and the spectrum has been restored. Nevertheless, the artificial intelligence (AI) results were based on only 2-3 overlapping pulse data and did not consider the effect of noise, so they did not solve realistic problems. Additional research is needed. In the future, we plan to conduct signal correction research using ≈10×10 mm small size detectors (GAGG, CZT etc.). Also, the performance evaluation of the measurement/analysis system is intended to be performed in an environment similar to the high radiation field of an actual nuclear facility.

Many manufacturers applying third party logistics (3PLs) have some challenges to increase their logistics efficiency. This study introduces an effort to estimate the weight of the delivery trucks provided by 3PL providers, which allows the manufacturer to package and load products in trailers in advance to reduce delivery time. The accuracy of the weigh estimation is more important due to the total weight regulation. This study uses not only the data from the company but also many general prediction variables such as weather, oil prices and population of destinations. In addition, operational statistics variables are developed to indicate the availabilities of the trucks in a specific weight category for each 3PL provider. The prediction model using XGBoost regressor and permutation feature importance method provides highly acceptable performance with MAPE of 2.785% and shows the effectiveness of the developed operational statistics variables.

Organic scintillator is easy to manufacture a large size and the fluorescence decay time is short. However, it is not suitable for gamma measurement because it is composed of a low atomic number material. Organic scintillation detectors are widely used to check the presence or absence of radiation. The fluorescence of organic scintillators is produced by transitions between the energy levels of single molecules. In this study, an organic scintillator development study was conducted for use in gamma measurement, alternative materials for secondary solute used in basic organic scintillators were investigated, and the availability of alternative materials, detection characteristics, and neutron/gamma identification tests were performed. In other words, a secondary solute showing an improved energy transfer rate than the existing material was reported, and the performance was evaluated. 7-Diethylamino -4-methylcoumarin (DMC), selected as an alternative material, is a benzopyrone derivative in the form of colorless crystals, has high fluorescence and high quantum yield in the visible region, and has excellent light stability. In addition, it has a large Stokes shift characteristic, and solubility in solvent is good. Through this study, it was analyzed that the absorption wavelength range of DMC coincided with the emission wavelength range of PPO, which is the primary solute. Through this study, it was confirmed that the optimal concentration of DMC was 0.04wt%. As a result of performing gamma and neutron measurement tests using a DMC-based liquid scintillator, it showed good performance (FOM=1.42) compared to a commercial liquid scintillator. Therefore, the possibility of use as a secondary solute was demonstrated. Based on this, if studies on changes in the composition of secondary solute or the use of nanoparticles are conducted, it will be possible to manufacture and utilize a scintillator with improved efficiency compared to the existing scintillator.

The safe, efficient and cost-effective decommissioning and dismantling of radioactive facilities requires the accurate characterization of the radionuclide activities and dose rate environment. And it is critical across many nuclear industries to identify and locate sources of radiation accurately and quickly. One of the more challenging aspects of dealing with radiation is that you cannot see it directly, which can result in potential exposure when working in those environments. Generally, semiconductor detectors have better energy resolution than scintillation detectors, but the maximum achievable count rates are limited by long pulse signals. Whereas some high pure germanium detectors have been developed to operate at high count rates, and these HPGe detectors could obtain gamma-ray spectra at high count rates exceeding 1 Mcps. However, HPGe detectors require cooling devices to reduce the leak currents, which becomes disadvantageous when developing portable radiation detectors. Furthermore, chemicalcompound semiconductor detectors made of cadmium telluride and cadmium zinc telluride are popular, because they have good energy resolution and are available at room temperature. However, CdTe and CZT detectors develop irradiation-induced defects under intense gamma-ray fields. In this Review, we start with the fundamentals of gamma rays detection and review the recent developments in scintillators gamma-ray detectors. The key factors affecting the detector performance are summarized. We also give an outlook on the field, with emphasis on the challenges to be overcome.

Ochratoxin A (OTA) is one of the most important mycotoxins owing to its widespread occurrence and toxicity including nephrotoxicity and potential carcinogenicity to humans. Since OTA is stable under most food processing conditions, OTA has been detected not only in a wide range of agricultural commodities such as cereal grains but also their processed products. Nonetheless, it is known that significant reduction of OTA may be achieved under higher temperature and alkaline conditions. In this study, the effects of retorting cooking process on the stability of OTA in spiked (20 μg/kg of dry weight basis) rice and oat porridge (10% solid content; w/v) in the presence and absence of baking soda was investigated using a laboratory horizontal steam retort system. The samples were heated in a pot at 85°C central temperature until it becomes gelatinized, packed in retort pouched, and heat-processed in pressurized retort machine (at 121°C for 25 min) followed by drying in 50°C oven overnight. Samples were analyzed for OTA by high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The reduction of OTA in retorted rice and oat porridge were 54% and 17%, respectively, while greater reduction of OTA was observed at increased amount of baking soda. The reduction of OTA in retorted rice porridge with 0.5% and 1% baking soda were 55% and 66%, respectively. In the retorted oat porridge, reduction of OTA was also evident to result in 30% and 48% with 0.5% and 1.0% of added baking soda, respectively. These results suggest that OTA in rice and oat may be reduced significantly by retorting process. In addition, added baking soda may positively impact the reduction of OTA.

To elucidate the effect of cellular phone electromagnetic wave (EMW) exposure on the developing cerebellar cortex of neonatal Sprague-Dawley rats, animals were exposed to cellular phone electromagnetic waves for 1 hr per day for 3 weeks. At the end of the experimental period, animals were sacrificed by cardiac perfusion, after which histological samples were prepared and observed microscopically. In the EMW exposure group, external granule cells were remained partially in the external granular layer without migrating into the internal granular layer. In addition, dark stained shrunken Purkinje cells with pyknotic nuclei increased and the outline of cells became irregular and showed degenerative signs, such as mitochondrial swelling and disrupted cristae. Moreover, the cisternae of rough endoplasmic reticula and Golgi complex were severely swollen. Bergmann glial cells adjacent to the dark stained Purkinje cells were swollen and cytoplasmic organelles were scant. Dark stained shrunken granule cells were also observed and the outline of cells was irregular. The results of the present study suggest that cellular phone EMW exposure to neonatal Sprague-Dawley rats leads to a partial delay of early migration of cerebellar cortical cells and degenerative changes in Purkinje cells, Bergmann glial cells and granule cells.

Staphylococcus (S.) aureus is commonly found on the skin and mucous membranes of animals. Moreover, some isolates producing staphylococcal enterotoxins (SE) are also responsible for food poisoning. This study was conducted to explore the prevalence of S. aureus enterotoxin from slaughtered pigs and cattle. A total of 202 carcass swabs were collected from slaughterhouses: 102 samples were taken from slaughtered pigs and 100 were taken from cattle, respectively. Among them, 16 (7.9%) from slaughtered pigs were found to contain S. aureus, while S. aureus was not isolated from any of the slaughtered cattle samples. Additionally, six (37.5%) of the S. aureus isolates contained genes that encode staphylococcal enterotoxin type A. Therefore, it is necessary to investigate the management of food-borne pathogens based on differences in the process by which pigs and cattle are slaughtered.

The entomopathogenic fungus Metarhizium anisopliae B is a powerful biological control agent against Monochamusalternatus, a crucial mediator of the pinewood nematode Bursaphelenchus xylophilus. In this study, production of destruxins(dtxs), insecticidal cyclic hexadepsipeptides, was monitored in the submerged culture of M. anisopliae B. Three typesof dtxs, i.e., destruxin A, B, and E, were produced during the culture. Among the three dtxs, the production yield ofdestruxin A was best, followed by destruxin B and E. Destruxin A production was increased when pH was controlledat 6.0, whereas production of destruxin E was not affected by the pH control. The highest yield of dtxs A, B, and Ewere 16.4, 7.3, and 6.1 mg L-1, respectively. Considering that process for dtxs production has not been optimized, M.anisopliae B has more powerful implication as a biocontrol agent.

Anthriscus sylvestris (L.) Hoffm. is a perennial herb found widely distributed in various regions of Korea, Europe, and New Zealand. The root of A. sylvestris have been extensively used in the treatment for antitussive, antipyretic, cough remedy in Oriental medicine, but the physiologically active function of the leaf of A. sylvestris is as yet unknown. In this study, we investigated the anti-cancer activity and the mechanism of cell death of water extracts of leaf of Anthriscus sylvestris (WELAS), on human FaDu hypopharyngeal squamous carcinoma cells. Our data showed that WELAS treatment inhibited cell viability in a concentration- and time-dependent manner. In addition, the treatment of WELAS markedly induced apoptosis in FaDu cells, as determined by the viability assay, DAPI stain and FACS analysis. WELAS also increased the proteolytic cleavage of procaspase-3, -9 and PARP (poly(ADP-ribose) polymerase). In addition, exposure to WELAS decreased the expression of Bcl-2 (an anti-apoptotic factor), but increased the expression of Bax (a pro-apoptotic factor), suggesting that mitochondria-dependent apoptotic pathways are mediated in WELAS-induced apoptosis. Taken together, these results indicate that water extracts of leaf of A. sylvestris inhibits cell growth and induces apoptosis via the mitochondrial-dependent apoptotic pathway in FaDu human hypopharyngeal squamous carcinoma cells. Therefore, we propose that the water extracts of leaf of A. sylvestris is a novel chemotherapeutic drug, having growth inhibitory properties and induction of apoptosis in human oral cancer cells.

Ochratoxin A, which is frequently detected in cereals and infant diets worldwidely, is a mycotoxin to damage mainly the kidney and liver. Because ochratoxin A is highly thermostable compound. it is necessary to study ways of reducing level of ochratoxin A by controling processing steps. However, food processes, including extrusion, expansion, roasting, and steam cooking, which are used in order to mitigate the contents of ochratoxin A, are known to produce polycyclic aromatic hydrocarbons, which are generated from radicals decomposed by pyrolysis. Therefore, this study analyzed the levels of 4 polycyclic aromatic hydrocarbons, benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based products made in high pressure and heating process. Rice samples were finely ground, and homogenized samples were alkaline treatement with 1 M KOH/EtOH and extracted with liquid-liquid extraction method using n-hexane. The extracted solution was pretreated with a silica cartridge. The purified solution was dried with nitrogen gas and dissolved in 1 mL of dichloromethane and injected into GC/MSD. We had overall recoveries for 4 polycyclic aromatic hydrocarbons spiked into rice samples ranging from 92.8 to 110.2%. The limit of quantitations of benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based product were 0.19 ng/g, 0.38 ng/g, 0.51 ng/g, and 0.31 ng/g, respectively. However, these 4 polycyclic aromatic hydrocarbons in all processed rice samples were not detected.

This study investigated the effect of dietary lysine and gamma-linolenic acid(GLA) levels on growth performance, carcass traits, and meat quality in finishing pigs. Pigs were provided with feed containing two different levels of lysine(0.45% and 0.75%) with three different levels of gamma-linolenic acid(0.0, 0.3, and 0.6%). Average daily gain(ADG) was significantly lower (p<0.01) in pigs provided with the lower level of lysine. In contrast, feed/gain(p<0.01), diet cost/gain(p<0.05), and intramuscular fat(p<0.01) were all significantly higher in pigs fed the lower level of lysine. Similarly, meat color scores(CIE L*, a*, and b*) and cooking loss were significantly higher(p<0.01) in pigs fed the lower level of lysine, whereas shear force(kg/2.5 inch2)was not affected by dietary lysine. The addition of GLA had no significant effect on any of the parameters measured. The results indicate that providing pigs with 0.45% lysine in their diet may help to increase intramuscular fat content, allowing the industry to produce pork products that meet consumer needs in Korea.

Varroa destructor and Tropilaelaps mercedesae mites are ectoparasitic to honey bee having similar life cycle and damage symptoms. Both invade into the last instar larval cell and reproduce during capped brood period of honey bee development. Female adult mites escape from the comb cell on the back of the emerging adult bee (phoretic period) and invade another cell for reproduction. Objective of this study was to study the effect of competitive interaction on each parasitic mite species population. We assessed population monitoring of host and parasitic mites. Honey bee population was monitored by approximating sealed brood and adult bees based on the coverage of the combs. Parasitic mites were monitored by detection technique like sugar shake, stick board, and sealed brood. This monitoring continued at weekly interval during 2008, 2014, and 2015. Additionally Invasion distribution of each species was checked. We calculated carrying capacity, population growth rate, and competition parameter from population monitoring data. Single parasitic mite, Varroa occurred and infestation increased continuously throughout the year in 2008. Co-occurrence of Varroa and Tropilaelaps in honey bee colonies was studied in 2014 and 2015. Carrying capacity was higher in single parasite infesting honeybee than parasites in co-occurrence. While using sugar method, carrying capacity of Varroa alone was found higher than in its co-occurrence with Tropilaelaps. Population growth rate of Varroa when tested alone was higher than its co-occurrence with Tropilaelaps in sugar method. Population growth rate of Varroa and Tropilaepas was higher in sticky method than sugar methods when they were tested in co-occurrence. Population growth rate is higher in Tropilaelaps (0.09) than Varroa (0.05) when both are tested in co-occurrence. We calculated competition parameter of Varroa and Tropilaelaps which was 1.9 and 0.53, respectively. Negative effect on regulation of carrying capacity and population growth rate is due to interspecies competition. Varroa population was higher than Tropilaelaps because there was high intraspecies competition among Tropilaelaps. Single Varroa or its co-occurrence with Tropilaelaps both can destroy honeybee colonies.