많은 연구에 따르면 Tenebrio molitor은 유충 단계에서 플라스틱을 섭취할 수 있다고 보고되었다. 이 연구의 목적은 T. molitor 유충의 성장과 발달에 발포폴리스티렌 섭취가 미치는 영향을 조사하는 것이다. 밀기울을 섭취한 유충의 성장률은 발포폴리스티렌을 섭취한 유충의 성장률보다 더 좋았고(p < 0.001) 발포폴리스티렌을 섭취한 유 충의 번데기로 전환되는 기간은 밀기울을 섭취한 유충의 번데기로 전환되는 기간보다 더 빨랐다(p < 0.001). 하지만 두 처리구간 생존율은 유의미한 차이가 없었다(p = 0.786). 이 결과에 따르면 발포폴리스티렌을 섭취한 유충은 체중 감소와 짧은 발육기간이 특징이지만 생존하는 것에는 문제가 없었다. 따라서 우리는 T. molitor가 플라스틱 폐기물 의 지속 가능하고 친환경적인 제거를 위한 주요 자원이라는 결론을 내렸다.

One of the key challenges for the commercialization of carbon nanotube fibers (CNTFs) is their large-scale economic production. Among CNTF spinning methods, surfactant-based wet spinning is one of the promising techniques for mass producing CNTFs. Here, we investigated how the coagulation bath composition affects the spinnability and the properties of CNTFs in surfactant-based wet spinning. We used acetone, DMAc, ethanol, and IPA as coagulants and analyzed the relationship between coagulation bath composition and the properties of CNTFs in terms of kinetic and thermodynamic coagulation parameters. From a kinetic perspective, we found that a low mass transfer rate difference (MTRD) is favorable for wet spinning. Based on this finding, we mixed the coagulant bath with solvent in a proper ratio to reduce the MTRD, which generally improved the wet spinning. We also showed that the coagulation strength, a thermodynamic parameter, should be considered. We believe that our research can contribute to establishment of surfactant-based wet spinning of CNTFs.

Haemaphysalis longicornis는 사람과 동물에게 여러 심각한 병원체를 전달하는 주요 매개체로, 한반도에 널리 분포하고 있다. H. longicornis는 Rickettsia spp., Borrelia spp., Francisella spp., Coxiella spp., 그리고 중증열성혈소판 감소증후군 바이러스 (SFTS virus) 등을 매개하는 것으로 알려져 있다. 국내에 서식하는 H. longicornis의 미생물 군집과 관련된 연구는 많이 진행되지 않은 것으로 확인되었다. 이 연구는 한반도 내 다양한 지역에서 채집된 H. longicornis의 미생물군집 다양성을 지역별, 성장 단계 및 성별에 따라 분석하였다. 2019년 6월부터 7월까지 질병관리청 권역별기후변화매개체감시거점센터 16개 지역에서 채집한 H. longicornis의 16S rRNA 유전자 V3-V4 영역을 PCR로 증폭 후 Illumina MiSeq 플랫폼으로 시퀀싱하였다. Qiime2를 활용한 미생물 다양성 분석을 통해 총 46개의 샘플에서 1,754,418개의 non-chimeric reads를 얻었으며, 평균 126개 의 operating taxonmic unit (OTU) 을 식별하여 총 1,398개의 OTU를 확인하였다. 대부분의 지역에서 Coxiella spp.가 우점종으로 나타났으며, 특히 Coxiella endosymbiont는 가장 높은 우점도를 보이며, Coxiella burnetii와 계통 발생 학적으로 유사한 것으로 확인되었다. 이 연구를 통해 분석된 결과는 각 지역의 H. longicornis 미생물군집 데이터 베이스 구축에 활용되었으며, 이를 통해 지역별 미생물군집의 특이성을 식별할 수 있게 하였다. 이는 한반도의 H. longicornis에 의한 질병 전파 연구와 이를 통한 공중보건 개선에 기여할 것으로 기대된다.

The purpose of this study is to select various insect species for healing resources and develop a healing program in order to use insect as a healing agriculture. In this study, there are two kinds of breeding kit were developed, one for Gryllus bimaculatus and the other for Oxya chinensis sinuosa. Using these insect breeding kits, we conducted a survey of 60 children and the elderly. In the case of children, the results of the insect breeding satisfaction showed that 30.6% said that the sound of crickets was very good, and 11.1% said that it was good. In addition, the higher the child's awareness of insects, the higher the proportion of children who wanted to raise insects in the future. As a result of a survey of seniors, 45.2% do not like insects and 51.6% are not interested, meaning that most seniors are not very interested in insects. However, the emotions after breeding insects showed positive results, with 45.2% saying their personality became brighter, 48.4% reducing their anger, 48.4% relieving their irritation, 54.8% relieving loneliness, 58.1% feeling more responsible, and 51.6% developing intimacy.

The ultimate objective of deep geological repositories is to achieve complete segregation of hazardous radioactive waste from the biosphere. Thus, given the possibility of leaks in the distant future, it is crucial to evaluate the capability of clay minerals to fulfill their promising role as both engineered and natural barriers. Selenium-79, a long-lived fission product originating from uranium- 235, holds significant importance due to its high mobility resulting from the predominant anionic form of selenium. To investigate the retardation behaviors of Se(IV) in clay media by sorption, a series of batch sorption experiments were conducted. The batch samples consisted of Se(IV) ions dissolved in 0.1 M NaCl solutions, along with clay minerals including kaolinite, montmorillonite, and illite-smectite mixed layers. The pH of the samples was also varied, reflecting the shift in the predominant selenium species from selenious acid to selenite ion as the environment can shift from slightly acidic to alkaline conditions. This alteration in pH concurrently promotes the competition of hydroxide ions for Se(IV) sorption on the mineral surface as the pH increases and impedes the selective attachment of selenium. The acquired experimental data were fitted through Langmuir and Freundlich sorption isotherms. From the Freundlich fit data, the distribution coefficient values of Se(IV) for kaolinite, montmorillonite, and illite-smectite mixed layer were derived, which exhibited a clear decrease from 91, 110, 62 L/kg at a pH of 3.2 to 16, 6.3, 12 L/kg at a pH of 7.5, respectively. These values derived over the pH range provide quantitative guidance essential for the safety assessment of clay mineral barriers, contributing to a more informed site selection process for deep geological repositories.

The domestic Pressurized Heavy Water Reactor (PWHR) nuclear power plant, Wolsong Unit 1, was permanently shut down on December 24, 2019. However, research on decommissioning has mainly focused on Pressurized Water Reactors (PWRs), with a notable absence of both domestic and international experience in the decommissioning of PHWRs. If proper business management such as radiation safety and waste is not performed, it can lead to increased business risks and costs in decommissioning. Therefore, the assessment of waste volume and cost, which provide fundamental data for the nuclear decommissioning process, is a crucial technical requirement before initiating the actual decommissioning of Wolsong Unit 1. Decommissioning radiation-contaminated structures and facilities presents significant challenges due to high radiation levels, making it difficult for workers to access these areas. Therefore, technology development should precede decommissioning process assessments and safety evaluations, facilitating the derivation of optimal decommissioning procedures and ensuring worker safety while enhancing the efficiency of decommissioning operations. In this study, we have developed a program to estimate decommissioning waste amounts for PHWRs, building upon prior research on PWR decommissioning projects while accounting for the specific design characteristics of PHWRs. To evaluate the amount of radioactive waste generated during decommissioning, we considered the characteristics of radioactive waste, disposal methods, packaging container specifications, and the criteria for the transfer of radioactive waste to disposal operators. Based on the derived algorithm, we conducted a detailed design and implemented the program. The proposed program is based on 3D modeling of the decommissioning components and the calculation of the Work Difficulty Factor (WDF), which is used to determine the time weighting factors for each task. Program users can select the cutting and packaging conditions for decommissioning components, estimate waste amount based on the chosen decommissioning method, and calculate costs using time weighting factors. It can be applied not only to PHWRs, but also to PWRs and non-nuclear fields, providing a flexible tool for optimizing decommissioning process.

금번 연구를 통해 외래산림해충 확산 분석 플랫폼 K-SDM (K-SDM)의 해충 분포 기능이 개발되었다. 해충 분포를 보여주는 기능은 2가지로 구현되며, 조사 자료를 바탕으로 현재 국내의 해충 분포를 나타내는 “외래산림 해충분포”기능과 데이터를 분석하여 예측되는 미래의 해충 분포를 제공하는 “외래산림해충예측”기능이 있다. “외래산림해충분포”는 조사자에 의해 현장에서 구축된 DB 현황을 지도상에 수치로 나타내며, 입력 기간, 해충 종 별로 구분이 가능하여 원하는 해충종의 분포를 선택하여 볼 수 있다. 지도 좌측에는 각 도별로 조사된 해충 개체수의 통계를 도표로 제공하여 수치상으로도 해충 분포를 파악할 수 있다. “외래산림해충예측”은 DB를 분석 하고 미래 기후 시나리오를 적용하여 도출한 미래의 해충 예측 분포도를 사용자에게 제공되며, 미리보기 이미지 와 함께 원본자료가 첨부되어 좀 더 자세한 정보를 열람할 수 있다. 본 플랫폼의 해충 분포 기능은 최근 기후변화 등으로 외래산림해충의 발생이 증가하는 추세에 맞춰 이들의 현재 분포와 미래의 분포양상을 조기 파악하여 이를 통한 추후 조기 방제 및 대응책 마련 등에 크게 기여할 것으로 기대된다.

최근 국내에서는 꿀벌 대량소실 현상이 2022년부터 전국적으로 발생하고 있다. 우리나라 뿐 만 아니라, 전세계 적으로 양봉산업에 큰 위협이 되고 있는 봉군붕괴현상은 2016년 미국에서 세계 최초로 보고되었다. 국내에서는 2022년 민관 합동조사 결과, 이상기온, 응애, 말벌 등이 주요 원인으로 지목되었다. 대량소실 현상을 보인 양봉농 가와 정상 농가의 병원체 검출 비교 결과, 유의성있게 검출이 증가되는 병원체는 발견되지 않았다. 그러나, Tyrophagus mite, Trypanosome, Lake Sinai virus, Apis mellifera filamentous virus 등의 신종 응애, 원충 및 바이러 스 감염이 추가로 확인되었다. 국내에서 새롭게 감염이 확인된 기생충과 병원체가 대량소실, 나아가 봉군붕괴현 상에 직간접적으로 영향을 주었을 것으로 사료되며, 지속적인 조사와 연구개발을 통해 기후등 환경변화에 따른 신종 질병 검색과 대책을 마련해야 할 것이다.

With the aging of nuclear power plants (NPPs) in 37 countries around the world, 207 out of 437 NPPs have been permanently shutdown as of August 2022 according to the IAEA. In Korea, the decommissioning of NPPs is emerging as a challenge due to the permanent shutdown of Kori Unit 1 and Wolsong Unit 1. However, there are no cases of decommissioning activities for Heavy Water Reactor (HWR) such as Wolsong Unit 1 although most of the decommissioning technologies for Light Water Reactor (LWR) such as Kori Unit 1 have been developed and there are cases of overseas decommissioning activities. This study shows the development of a decommissioning waste amount/cost/process linkage program for decommissioning Pressurized Heavy Water Reactor (PHWR), i.e. CANDU NPPs. The proposed program is an integrated management program that can derive optimal processes from an economic and safety perspective when decommissioning PHWR based on 3D modeling of the structures and digital mock-up system that links the characteristic data of PHWR, equipment and construction methods. This program can be used to simulate the nuclear decommissioning activities in a virtual space in three dimensions, and to evaluate the decommissioning operation characteristics, waste amount, cost, and exposure dose to worker. In order to verify the results, our methods for calculating optimal decommissioning quantity, which are closely related to radiological impact on workers and cost reduction during decommissioning, were compared with the methods of the foreign specialized institution (NAGRA). The optimal decommissioning quantity can be calculated by classifying the radioactivity level through MCNP modeling of waste, investigating domestic disposal containers, and selecting cutting sizes, so that costs can be reduced according to the final disposal waste reduction. As the target waste to be decommissioning for comparative study with NAGRA, the calandria in PHWR was modeled using MCNP. For packaging waste container, NAGRA selected three (P2A, P3, MOSAIK), and we selected two (P2A, P3) and compared them. It is intended to develop an integrated management program to derive the optimal process for decommissioning PHWR by linking the optimal decommissioning quantity calculation methodology with the detailed studies on exposure dose to worker, decommissioning order, difficulty of work, and cost evaluation. As a result, it is considered that it can be used not only for PHWR but also for other types of NPPs decommissioning in the future to derive optimal results such as worker safety and cost reduction.

Once a radioactive material is released from the nuclear power plant (NPP) by accident, it is necessary to understand the behavior of radioactive plume to protect residents adequately. For this, it is essential to measure the radiation dose rate around NPPs at important locations. Our previous study developed a movable radiation detector that can be installed quickly in an accident to measure gamma dose rate in areas where environmental radiation monitoring system is not installed. The data measured by the detector are transmitted to the server in real-time through LoRA wireless communications. There are two methods to use LoRA communications; one is self-network, and the other is the network provided by the mobile carrier. A signal receiver, called a gateway, should be equipped near the installation location of radiation detectors to use a self-network without using the mobile carrier’s system. In other words, the movable radiation detectors we made can function if there should be any gateway near them. The distance capable of communication between gateway and detector is about 8 km in an open area without significant obstacles. Korea has many significant obstacles, such as mountains around most NPPs. Thus, the gateways could be installed in the proper position before the accident to operate the movable radiation detectors without problems. If the gateway is located at a high position like a mountain top, it could cover a wide area. In this study, the elevation database in the area around the NPPs was collected and analyzed to determine where gateways should be installed. The analysis range is limited in the urgent protective action planning zone. The optimization was also performed to minimize the number of gateways.

Colon cancer has been considered a leading cause of cancer-associated death. Folic acid is a vitamin necessary for cellular physiological functions and cell viability. However, the association between folic acid intake and colon cancer has been examined in several prospective cohort studies are controversial. This study investigated the effects of folate intake on colon carcinogenesis and oxidative stress in an azoxymethane (AOM)/dextran sodium sulfate (DSS) institute for cancer research (ICR) mouse model. Thirty male ICR mice (5 weeks old) were divided into the control group and the experimental group supplied 0.03% folic acid via drinking water (50 mL/week/mouse) for 6 weeks. To induce colonic pre-neoplastic lesions, the animals were subcutaneously injected three times weekly with AOM (10 mg/kg body weight), followed by 2% DSS in drinking water for a week. Folic acid supplementation significantly suppressed the total number of aberrant crypt foci and aberrant crypts. Histological image data showed that folic acid supplementation attenuated neoplastic change. In addition, we measured the thiobarbituric acid reactive substances concentration of dry feces samples to identify the effect of folic acid on reactive oxygen accumulation. The folic acid supplementation group had reduced reactive oxygen species levels in dry feces compared to the control group. In conclusion, these findings indicate that folic acid suppresses colon carcinogenesis and oxidative stress in an AOM/DSS mouse model.

Nanostructured ZnO materials have been studied extensively because of their functional properties. This paper presents a composite material of zinc oxide quantum dots (ZnO QDs) and porous carbon using a one-step carbonization process. The direct carbonization of a metal–organic complex generates mesostructured porous carbon with a homogeneous distribution of ZnO QDs. The structural and morphological properties are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The resulting ZnO QDs@porous carbon composite delivers a high specific capacity of 990 mAh g−1 at 100 mA g−1, 357 mAh g−1 at 2 A g−1, and high reversibility when evaluated as an anode for lithium ion batteries.

We report the discovery of a giant exoplanet in the microlensing event OGLE-2017-BLG-1049, with a planet―host star mass ratio of q = 9.53 ± 0.39 × 10-3 and a caustic crossing feature in Korea Microlensing Telescope Network (KMTNet) observations. The caustic crossing feature yields an angular Einstein radius of θE = 0.52 ± 0.11 mas. However, the microlens parallax is not measured because the time scale of the event, tE ≃ 29 days, is too short. Thus, we perform a Bayesian analysis to estimate physical quantities of the lens system. We find that the lens system has a star with mass Mh = 0.55+0.36 -0.29 M⊙ hosting a giant planet with Mp = 5.53+3.62 -2.87 MJup, at a distance of DL = 5.67+1.11 -1.52 kpc. The projected star{planet separation is aㅗ = 3.92+1.10 -1.32 au. This means that the planet is located beyond the snow line of the host. The relative lens{source proper motion is μrel ~ 7 mas yr-1, thus the lens and source will be separated from each other within 10 years. After this, it will be possible to measure the flux of the host star with 30 meter class telescopes and to determine its mass.

We studied the infection rate of and various metacercariocidal approaches to controlling Gymnophalloides seoi for prevention of human infection in cultured and natural oysters in Korea. The selected survey areas were Aphae-do (Shinan-gun, Jeollanam-do), which is an endemic area for G. seoi, and Tongyeong (Geonsangnam-do), which is the main production area of oysters in Korea. In the Tongyeong area, the metacercariae of G. seoi were not detected in cultured oysters (0/201) or wild oysters (0/134). Seventy-two G. seoi metacercariae were observed in 33 of 265 natural oysters collected from Aphae-do; however, metacercariae were not detected in the cultured oysters (0/1101) purchased from the Daejeon Fish Market. To investigate the viability of G. seoi metacercariae, various metacercariocidal treatments were used with 3.5% saline and oyster juice used as positive controls. The metacercariae survived for 75.4 h in 3.5% saline and 112.6 h in oyster juice. After the metacercariocidal treatment, G. seoi metacercariae were survived for 13.29 min in tap water, < 20 sec in 4.3% vinegar, no effect in a rinse of the whole oyster body in 70°C water for 1 sec, but 1 sec in a rinse of the whole oyster body in 90°C water for 1 sec. The greatest metacercariocidal effect on G. seoi was from rinsing oysters in 90°C water followed by those from treatment with 20% ethyl alcohol, 4.3% vinegar, and tap water. However, we suggest that the most actual prevention to G. seoi human infection is rinsing the oysters with tap water for at least 30 min.

Chamaecyparis obtusa is one of the economical conifers planted in Korea due to its good quality timber and wood characteristics. Individuals of C. obtusa containing high terpenes (HT) and low terpenes (LT) were selected for by colorimetric method. The HT of C. obtusa was delayed in wilting against various abiotic stresses compared to the LT plants. The HT group exposed to UV did not significant influence the chlorophyll content, and the chlorophyll value was higher in the HT group than the LT group. Also, chilling treatment (5℃) did not significant influence on the chlorophyll content. However treatment at -4℃ showed relatively low chlorophyll content in the LT group than the HT group. Plants exposure to high temperature was not a difference between the HT and the LT group. However, treatment at 38℃ influenced the chlorophyll content that was increased exposure time-dependently. In salt treatments, chlorophyll in the HT group was lower at high concentrations (300 and 500 mM) of NaCl. However, chlorophyll content increased to slightly in treatment time-dependently, which is 6.7% to 40%. H2O2 treatment has been a negative effect on the chlorophyll content in the HT group. All concentration of H2O2 decreased the chlorophyll content of 5% to 35%. Plants containing high terpenoids were resisted against some abiotic stress such as salt and H2O2. Our results implied that terpenoids could cause various abiotic stress resistance. These results could be utilized for efficient management and biomass production during forest silvicultures.

The present study was conducted to evaluate the effects of high levels of nutrients on the growth performance, blood metabolites and carcass characteristics of Hanwoo cattle. Eighteen Hanwoo steers were fed two types of diets: 1) Nine animals were fed the conventional diet including typical levels of crude protein (CP) and total digestive nutrients (TDN), and 2) Nine animals were fed the treatment diet including high levels of CP and TDN. The average body weight (BW) and dry matter intake (DMI) were greater (P < 0.05) in the treatment group than in the conventional group at early and late fattening stages. Also, in the treatment group, the average daily gain (ADG) was greater (P < 0.05) at the late fattening stage. The serum total lipid and cholesterol levels were higher (P < 0.05) in the late fattening stage of treatment group. The carcass weight, total fat weight, longissimus muscle area and the grade of meat quality were also greater (P < 0.05) in the treatment group than the conventional diet group. This study demonstrates that high levels of CP and TDN exhibit a positive effect on the growth performance and carcass characteristics, indicating that high levels of CP and TDN can be used as a cost-effective feeding program for Hanwoo cattle by shortening the feeding period.