본 연구는 작약의 품종간 개화시기 차이와 저온에서 장기 저 장이 가능한 품종을 선발하여 절화 유통 기간을 연장하기 위하 여 수행하였다. 작약 24품종을 대상으로 2022년 국립원예특작 과학원 시험포장에서 개화시기와 절화 품질을 조사하였다. 봉오 리 상태에서 수확한 작약을 건조 저장법으로 -1℃에서 60일 저장한 후 절화 수명과 절화품질을 조사하였다. ‘의성작약’은 홑 꽃이었고 나머지 품종은 겹꽃이었다. 개화시기는 5월 10일부터 18일 사이였으며, ‘Etched Salmon’, ‘Monsieur Jules Elie’, ‘Gilbert’, ‘Henry Bockstoce’는 개화일이 5월 10일로 가장 빨랐고, ‘Elsa Sass’는 5월 18일로 가장 늦었다. 식물체 키는 74.6∼107.8cm 였고, 절화 무게는 ‘Henry Bockstoce’ 품종 이 89.8g으로 가장 무거웠고, ‘Angel Cheeks’ 품종이 26.7g으 로 가장 가벼웠다. 꽃의 주된 색은 흰색, 빨강색, 분홍색, 자주색 이었다. -1℃에서 60일간 저장 후에 꽃과 잎의 상태가 아주 양 호한 품종은 ‘Kansas’, ‘Ole Faithful’, ‘Sonw Mountain’이 었다. 절화수명은 ‘Nick Shaylor’ 품종이 8일로 가장 길었고, 다음으로 ‘Blush Queen’, ‘Elsa Sass’ 품종이 7일이었으며, ‘Gilbert’, ‘Highlight’ 품종이 1일로 가장 짧았다. 작약은 저온 장기 저장에서 일부 품종을 제외하고는 꽃과 잎에 저온장해 증 상이 발생하였다. 이와같은 결과는 작약재배시에 품종 선택과 수확후 저온 장기 저장을 통하여 유통기간을 연장하고 하고자 할 때 기초자료로 활용될 수 있을 것으로 기대된다.
We introduce a method for preserving yellow mealwom (Tenebrio molitor) larvae for an extended period and show that a high percentage of larvae can survive in good health under low-temperature storage conditions combined with specific diapause termination conditions. When storing larvae for 140 days, the storage temperature can be varied based on our goals, giving us control over yellow mealworm production to meet specific demands. To produce adult beetles, storing larvae at 15 ℃ with wheat bran and ending diapause at 30 ℃ resulted in 90% pupation rate, with 60% becoming adults in 21 days. If our aim is larvae production, storing them at 10–12 ℃ with wheat bran and ending diapause at 25–30 ℃ allows the larvae to reach a suitable weight for processing. This approach ensures long-term storage of yellow mealworm larvae and provides a practical way to control their development, allowing efficient mass production tailored to market demands.
In this study, an appropriate modified atmosphere packaging (MAP) condition to minimize physiological disorders while lowering weight loss was sought. To reduce weight loss during storage, kimchi cabbages packed with 0, 32, 40, 48 perforated low-density polyethylene (LDPE) films, with a diameter of 14 mm, were stored in pallet units for 90 days at 1-2oC, and their loss rate, physiological disorders, total bacteria count, pH, and solid content were analyzed. It was found that as the number of holes increased, the weight loss ratio increased proportionally. However, the difference between the perforations was relatively small compared with the sample without film packaging. On the other hand, it was also observed that the lower the number of holes was, the lower the incidence of physiological disorder was because the cold air penetrated through the perforated hole while inhibiting physiological effects, releasing heat and carbon dioxide generated by respiration. Considering the weight loss rates and physiological disorders such as black speck and soft rot, the kimchi cabbage packed with 48 perforated films (73.9 cm2) exhibited the most satisfactory condition. Using this storage condition, along with 2-3oC temperature and 91-95% relative humidity inside the pallet, a highly suitable condition for kimchi processing was obtained to secure kimchi cabbage.
The exosomes are the most studied nanometer-sized extracellular vesicles (40-100 nm) in eukaryotic cell. Exosomeharbors various molecular components of their cell origin, including nucleic acids and proteins, and it is involved in intraand intercellular communication. These characteristics make exosomes to be a prospective biomarkers, therapeutic agents,or drug delivery vehicles. Edible insect industry is rapidly growing up in Korea. The insect exosomes were isolated fromthe larvae of Korean rhinoceros beetle, Allomyrina dichotoma, and White-spotted flower chafer, Protaetia brevitarsis, sothat they can be used for diagnosis of insect disease. The stable preservation of exosome is very important for diagnosisand research, especially for long term storage. Here, the stable recovery of exosome isolated from hemolymph of A. dichotomalarva was evaluated by analyzing exosomal protein and RNA after storage in -70°C for three months.
Quality assessment of sweet persimmon or “Fuyu” was evaluated over room temperature distribution periods after 40-day storage at 0oC cold room. All Hunter’s values (L, a, and b) of sweet persimmon were significantly decreased after 4-day room temperature distribution while the flesh firmness was drastically decreased after 3-day room temperature distribution. Glucose and fructose contents were significantly increased by the degradation of sucrose after 3-day room temperature distribution. The highest extraction yield was obtained in the flesh of persimmon. Extraction yields of each part of “Fuyu” persimmon were 15.53% for flesh, 10.53 for seed, and 13.83 for flower bud. However, the total phenolic content of flesh was 4.8 μg/mg which was extremely lower than that of the seed (175.5 μg/ mg) and flower bud (178.2 μg/mg) of sweet persimmon. With high phenolic content, both the flower bud and seed of sweet persimmon showed excellent antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis( 3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging test. The results showed a great potential for byproducts (seed and flower bud) of long-term, cold-stored sweet persimmon “Fuyu” as a good antioxidant material for novel functional foods.
본 실험은 1-MCP처리와 저장방법이 아스파라거스의 신선도 유지에 미치는 영향을 알아보고자 수행하였다. 1-MCP 처리는 MA 조건과 유공필름(관행조건)에 처리 되었으며 무처리구를 대조구로 사용하여 저장하였다. 처리된 아스파라거스는 40일 동안 4oC에 저장되었다. 저장 중 생체중 감소율은 1-MCP 처리를 포함한, MA저장 처 리구에서 0.2% 이하였고 유공필름에 저장된 1-MCP 처리는 생체중 감소율이 저장 20일 후부터 다소 낮아졌다. 포장 내 이산화탄소 농도는 MA저장 처리구 모두 최적 CA 조건인 5-12%(CO2)의 농도를 유지하였고, 산소농도는 5-15%를 유지하였다. 에틸렌 농도는 MA저장 1- MCP처리구가 가장 낮았다. 저장 최종일의 외관상 품질, 이취, 경도, 당도, 그리고 Hue angle 값은 MA저장에서 관행저장보다 우수하였으나 1-MCP처리간 차이는 없었다. 이상의 결과로 1-MCP처리는 아스파라거스의 품질 및 저장성에 영향을 미치지 않았다.
본 연구는 다양한 조건에서 장기 보존한 느티만가닥버섯 균주의 균사 생존력과 재배성능 검증을 수행하였다. 균사 생존력은 장기 보존된 균주를 9, 21,33, 45개월 단위로 해동하여 PDA 평판배지에 접종한 다음 1, 2, 3, 4, 5차 계대배양에 따른 균사 생장길이를 측정하여 검증하였다. 액체질소에 보존한 균사를 해동 직후 실시한 1차 계대배양에서는 동결보호제로써 Glycerol 10%를 단용으로 처리한 실험구에서균사생장이 저조한 결과를 나타내었으나, 5차 계대배양에서는 버섯 균사의 생장력이 다른 실험구와 동일한 수준으로 회복되어, 저장방법에 따른 균사의 생존력에는 큰 영향이 없는것으로 판단된다. 그러나 느티만가닥버섯을 액체 질소에 장기간 보존하고자 할 때는 동결보호제로 사용되는 Glycerol 10%에 Trehalose5%를 첨가하여 보존해야 균사의 생존력을 유지하는데 도움이 된다.장기 저장에 따른 느티만가닥버섯 균주의 재배 성능 시험에서는 4oC 사면배지에 보호제로써 mineraloil을 사용하는 것이 사면배지 자체로 보존하는 것에비해 수확량이 감소하는 결과를 나타내므로 장기 저장시에 mineral oil을 사용하는 것은 지양해야 할 것으로 판단된다.
본 연구는 기존의 농가 보급형 고구마 저장고에 가열기(본체), 환기팬, 배풍구 팬, 습도 조절을 위한 관으로 구성된 간이 큐어링 설비를 부가시킨 후, 그 효과를 검증하기 위하여 수행되었다. 6일간의 큐어링 처리 기간 동안 저장고 내 기온 및 상대습도는 32℃, 90%로 설정되었다. 고구마의 저장 기간(6 개월) 동안 1개월에 1회씩 표본을 수집하여 물리화학적 품질을 측정한 결과, 부패율과 부패 정도를 함께 보여주는 McKinney Index는 큐어링 처리구의 경우 0.83%였으며, 큐어링 처리를 하지 않은 대조구의 경우 5.08%였다. 큐어링 처리구의 경도 및 당도, 건물율은 모두 대조구보다 높았으며, 대조구의 표피색이 큐어링 처리구보다 빠르게 변하여 큐어링 처리가 저장기간 동안 고구마의 변색을 지연시켰음을 알 수 있었다. 본 연구를 통하여 간이 큐어링 설비를 이용한 큐어링 처리는 초기 비용이 많이 소모되는 일반 큐어링 설비를 대체하여 고구마의 물리화학적 품질을 증진시킬 수 있으며, 저장 기간을 늘릴 수 있음을 알 수 있었다.
Preservation of sperm is essential for long-term storage of valuable animal genetic resources and for the conservation of threatened mammalian species undergoing progressive extinction. In this study, using pig as a model system, we evaluated the feasibility of germ-plasm preservation via sperm cell lyophilization. We show that, pig sperm can be successfully lyophilized and stored in a liquid nitrogen-free condition for at least 6 months. Intracytoplasmic injection of lyophilized sperm (ICSI), stored at 4℃ for four months, into in vitro matured pig oocytes could successfully develop up to blastocyst stage (13.0±3.0%). Lyophilized sperm could also be stored at room temperature for at least three weeks without further compromising their in vitro development up to the blastocyst stage (14.6±3.2 vs. 16.6±5.1%; p>0.05). Blastocysts produced from ICSI of lyophilized sperm stored at 4℃ or room temperature contained similar number of cells per blastocyst (44.9±3.2 vs. 44.0±4.3; p>0.05) but was significantly lower than those produced from non-lyophilized fresh sperm (52.1±5.8 p>0.05). Interestingly, use of a custom-designed HEPES-buffered, calcium-free, defined medium for the lyophilization resulted in normal post-ICSI embryonic development up to blastula stage (23.4±2.8 vs. 24.0±2.9%) and, the resultant blastocysts contained similar number of cells per blastocyst (47.9±4.3 vs. 50.6±7.0) compared to those generated from non-lyophilized fresh sperm (p>0.05). These lyophilized sperm could also be stored at room temperature for at least three weeks with slight reduction in post-ICSI embryonic development (19.6±1.4%). Therefore, these results suggest that, pig sperm could be successfully and efficiently lyophilized for their long-term storage at 4℃. Lyophilization of sperm could be a practical option for long-term storage of mammalian germ-plasm.
본 연구의 목적은 3주 동안 장기간 냉각상태로 보관된 개 정자의 기능적 특성을 알아보고자 두 종류의 정자 희석액, Glucose-BSA(G-BSA), Dimitropoulos-II(BIMI)가 정자의 기능적 특성에 미치는 영향을 알아보고자 한다. 개 정액을 수지법에 의해 채취하여 원심분리한 후 정장은 제거하였다. 정자를 G-BSA나 DIMI으로 희석하여 최종 농도를 sperm/ml로 하였다. 희석된 정자를 정자 운송 시스템을 이용하여 루지애나 주립 대학
진딧물 포식성 무당벌레의 성충을 대상으로 저온처리에 의한 생식적 휴면을 유도하였다. 성충의 인위적인 생식적 휴면의 유지는 4℃에서 5개월 정도까지 가능하며 먹이의 공급이 필요하지 않아 경제적인 무당벌레의 저장법이라 할 수 있다. 하절기를 포함한 계절에 구분 없이 무당벌레의 성충의 저온저장이 가능하여 필요시 어느 때라도 진딧물 발생지에 무당벌레를 공급할 수 있게 되었다. 휴면 후 25℃에서 수명과 산란력이 우수하며 생식호르몬인 juvenile hormone(JH)의 합성 유사체인 methoprene은 암컷의 초반기 생식력을 증진시키는 효과를 나타낸다.
To develop a kimchi with high sensory quality and storage stability, the optimum pasteurization time and temperature were investigated. Sliced kimchi with different acidity (0.3, 0.5, and 0.8%) was prepared and pasteurized at 65 or 75oC, then the microbiological (number of total aerobic bacteria, lactic acid bacteria, and yeasts), physicochemical, and sensory changes were measured. The viable counts of total aerobes, lactic acid bacteria, and yeasts as well as the values of pH and acidity changed rapidly in control. However, the growth of microorganisms was controlled by pasteurization treatments, and the changes of pH and acidity in the treated kimchi were much smaller than those of control, although acidity of the samples was different at the initial state. The sensory results indicated that the overall quality of kimchi samples pasteurized at 0.3 or 0.8% acidity was relatively lower than that for the samples at 0.5% acidity. Particularly, kimchi pasteurized at 65oC were high scored in quality attributes compared to the other samples, with preserving a desirable flavor during whole storage period.
In this research, a detailed analysis of the decay heat contributions of both actinides and non-actinides (fission fragments) from spent nuclear fuel (SNF) was made after 50 GWd·tHM−1 burnup of fresh uranium fuel with 4.5% enrichment lasted for 1,350 days. The calculations were made for a long storage period of 300 years divided into four sections 1, 10, 100, and 300 years so that we could study the decay heat and physical disposal ratios of radioactive waste in medium- and long-term storage periods. Fresh fuel burnup calculations were made using the code MCNP, while isotopic content and then decay heat were calculated using the built-in stiff equation solver in the MATLAB code. It is noted that only around 12 isotopes contribute more than 90% of the decay heat at all times. It is also noted that the contribution of actinides persists and is the dominant ether despite decreasing decay heat, while the effect of fission products decreases at a very rapid rate after about 40 years of storage.
To investigate the mechanical integrity of spent nuclear fuel, the failure behavior of the cladding tube was examined under accident conditions. According to the SNL report, the failure behavior of cladding can be broadly classified into two types. The first is failure due to bending load caused by falling. The second is failure due to pinch load caused by space grid. In this study, mechanical integrity was evaluated through the stress intensity factor applied to the crack in failure behavior due to bending load. Since the exact value of the impact load due to fall was unknown, the load was applied by increasing the value up to 200 G in 20 G increments. The size of the crack is an important input variable, and 300 um was given by referring to the EPRI report, and the elastic modulus, a material property that determines the stress field, was given 75.22 GPa by referring to the FRAPCON code. Since the relationship between the direction of stress and the direction of the crack is also a major variable, simulations were conducted for both cracks perpendicular to and parallel to the stress direction. It was confirmed that at a load of 200 G, when the crack was parallel to the stress direction, stress concentration did not occur and had a very low stress intensity factor 0.01 √. When perpendicular to the direction of stress, the stress intensity factor showed a value of 1 √. However, considering that the critical value of the stress intensity factor due to hydride is 5 √, it can be seen that perpendicular result also ensures the mechanical integrity of the cladding.
Commercial operation of KORI Unit 1 ended in 2017, and the final decommissioning plan is currently under approval from the KINS. In order for the dismantling waste to go to the repository, it is judged that the radioactive waste generated during the commercial operation should be treated and disposed in advance. Among these radioactive wastes, spent filters contain various radionuclides. The radiation dose rate from the radiation coming out of the filters ranges from a low dose rate to high dose rate. Therefore, in order to handle the spent filters, a remote processing system is required to reduce the radiation exposure of workers. This paper evaluates the radioactive inventory of filters that are stored in the filter room at the KORI unit #1. For this purpose, a method for predicting the radioactivity of each nuclide in the filter, based on the radiation dose rate, has been described using the MicroShield code, which is a commercial shielding code. The information on the filters in the field has only the creation date, type, size, and surface dose rate. In order to evaluate the radioactivity inventory using such limited data, it is possible to know the nuclide radioactivity ratio in the filter. We took out some of the filters stored on site and measured from using the ISCOS system, a gamma nuclide analyzer. The radioactivity of each nuclide in the filter was inferred by modeling with the MicroShield code, based on the radiation dose rate and the radioactivity value of each nuclide measured in the field.
Research on the safety of nuclear spent fuel has been heavily experimented and modelled from a mechanical perspective. The issues of corrosion, irradiation creep, hydride and hydrogen embrittlement have been addressed more than two decades since the early 2000s. Among these degradation behavior, hydrogen embrittlement and hydride reorientation have been the most important topics for establishing the integrity of nuclear spent fuel and have been studied in depth. In order to assess the safety of spent nuclear fuel, firstly, it is necessary to establish the safety criteria in all nuclear cycle, i.e., the failure criteria guidelines for nuclear fuel assemblies and nuclear fuel rods, and then examine the safety analysis. The contents of U.S.NRC Regulations, Title 10 General, Chapter 1 Code of Federal Regulation (CFR), Part 50, 71 and 72, describe the safety criteria for the safety assessment of nuclear fuel assemblies and nuclear fuel rods. In this study, technically important points in safety analysis on nuclear fuel are checked through the reference of those NRC regulation. As result, we confirmed that the safety assessment of nuclear fuel after 20 years of interim storage is now being tested by ORNL and PNNL. There are not quantitative criteria related to material safety. However qualitative criteria which is dependent on environmentally condition describe the safety analysis. There is some literature study about DBTT, yield stress, ultimate tensile strength, flexural rigidity data. In FRAPCON code Modelling of yield strength and creep had been established, but radial hydride or hydride reorientation has not considered.