큰징거미새우(Macrobrachium rosenbergii)는 양식 시설 내에서 체색 불량 및 갑각 약화와 같은 문제로 경제적 손실을 겪고 있다. 이 종은 동물성 원료 기반의 사료로 양식되지만, 야생에서는 식물체 비중이 높은 detritus를 주로 섭취한다. 새우가 야생에서 섭취한 식물체는 기본 영양소 뿐만 아니라 체색의 재료인 카로티노이드의 공급원이기도 하다. 개나리(Forsythia koreana)는 우리나라에 널리 분포하는 꽃나무로 잎에는 황색 당근에 버금가는 양의 카로티노이드가 함유 되어 있다. 본 연구에서는 큰징거미새우에게 개나리 잎을 공급하여 체색 및 건강도에 미치는 효과를 조사하였다. 실험사료는 「배합사료 100%(대조구), CON」, 「배합사료 80%+개나리 잎 분말 20%, FP」, 「배합사료 80%+가공하지 않은 개나리 잎 20%, FL」의 세 가지였으며, 각 조건 의 사료를 평균 체중 1.1 ± 0.2 g의 어린 새우들에게 10주간 공급하였다. 실험 결과, 체색의 경 우, CON의 새우들은 일관적으로 투명한 상아색을 띠었으나, FP와 FL 새우의 경우 사육일의 경과에 따라 푸른색을 거쳐 암갈색으로 변화하였다. 생존과 성장은 CON과 FP 또는 FL 사이에 유의한 차이가 없었다. 간췌장을 조직학적으로 비교한 결과, hepatopancreatic tubule의 구성 세포 중 B cell의 vacuole 크기가 CON에 비해 FP과 FL에서 훨씬 컸다. B cell의 vacuole은 영 양소의 흡수 및 소화의 역할을 하며, 개나리 잎의 공급이 큰징거미새우의 건강에 긍정적으로 작용했을 가능성을 시사한다. 이상의 결과는 큰징거미새우의 양식에 개나리 잎을 활용하면 성장 저해 없이 체색의 개선 및 건강도의 향상을 기대할 수 있음을 보여준다.
In Korea, most temporary storage facilities for spent nuclear fuel are nearing saturation. As an alternative to this, the 2nd basic plan for high-level radioactive waste management specified the operation plan of dry interim storage facility. Meanwhile, the NSSC No. 2021-19 stipulates that it is necessary to evaluate the possibility and potential effect of accident before operating interim storage facility. Therefore, this study analyzed the categories of accident scenarios that may occur in dry storage facility as part of prior research on this. We investigated the case of categorization of dry storage facility accident scenarios of IAEA, NRC, KAREI, and KINS. The IAEA presented accident scenarios that could occur in on-site dry storage facility operated with silo and cask method. NRC has classified accident scenarios in dry storage facility and estimated the probability of accidents for each. KAERI and KINS selected major accident scenarios and analyzed the processes for each, in preparation for the introduction of dry storage facility in Korea in the future. Overall, a total of 10 accident scenarios were considered, and the scenarios considered by each institution were different. Among 10 scenarios, cask drop and aircraft collision were included in the categorization of most institutions. The results of this study can be used as basic data for cataloging accidents subject to safety evaluation when introducing dry interim storage facility in Korea in the future.
어류의 번식은 뇌에서 분비되는 다양한 신경호르몬과 뇌하수체에서 분비되는 생식소 자극 호 르몬에 의해 조절된다. 극동산 뱀장어(Anguilla japonica)의 번식도 이 호르몬들의 작용에 의해 조절되지만 성 성숙 시 신경호르몬이 뇌하수체 호르몬을 조절하는 방법은 완전히 밝혀지지 않 았다. 이전 연구에 의하면 progesterone (P4), melatonin 및 serotonin (5-HT) 등과 같은 신경호 르몬이 일부 어류의 번식 과정 조절에 관여하는 것으로 밝혀졌다. 본 연구에서는 뱀장어의 뇌 하수체를 초대 배양하였고, 안정화된 뇌하수체 세포에 P4, 17β-estradiol (E2), melatonin 및 5- HT를 처리하였다. 이후 처리된 호르몬의 작용이 뇌하수체 세포에서 번식 관련 호르몬인 FSHβ, LHβ, GH 및 SL mRNA 발현에 어떤 영향을 미치는지 조사하였다. 본 연구를 수행한 결과, P4는 뇌하수체 세포에서 FSHβ와 LHβ 발현을 증가시켰고, melatonin은 FSHβ와 LHβ 뿐만 아니라 GH 와 SL의 발현을 증가시켰다. 하지만 5-HT는 이 유전자의 mRNA 발현에 유의한 영향을 미치지 않았다. 이상의 결과는 P4 또는 melatonin이 뱀장어의 초기 성 성숙에 중요한 역할을 할 수 있음을 의미한다.
In Korea, the construction of dry storage facilities for spent nuclear fuel is being promoted through the 2nd basic plan for high-level radioactive waste management. When operating dry storage facilities, exposure dose assessment for workers should be performed, and for this, exposure scenarios based on work procedures should be derived prior. However, the dry storage method has not yet been sufficiently established in Korea, so the work procedure has not been established. Therefore, research is needed to apply it domestically based on the analysis of spent nuclear fuel management methods in major overseas leading countries. In this study, the procedure for receiving and storing spent nuclear fuel in a concrete overpack-based storage facility was analyzed. Among the various spent nuclear fuel management systems, the metal overpack-based HI-STAR 100 system and the concrete overpackbased HI-STORM 100 system are quite common methods in the United States. Therefore, in this study, work procedures were analyzed based on each final safety analysis report. First, the HI-STAR 100 overpack enters the facility and is placed in the transfer area. Remove the impact limiter of the overpack and install the alignment device on the top of the overpack. Place the HI-TRAC, an on-site transfer device, on top of the alignment unit and remove the lids of the two devices to insert the canister into the HI-TRAC. When the canister transfer is complete, reseat the lid to seal it, and disconnect the HI-TRAC from the HI-STAR 100. Raise the canister-loaded HI-TRAC over the alignment device on the top of the HI-STORM 100 overpack and remove the lids of the two devices that are in contact. Insert the canister into the HI-STORM 100 and reseat the lid. The HI-STORM 100 loaded with spent nuclear fuel is transferred to the designated storage area. In this study, the procedure for receiving and storing spent nuclear fuel in a concrete overpack-based storage facility was analyzed. The main procedure was the transfer of canisters between overpacks, and it was confirmed that HI-TRAC was used in the work procedure. The results of this study can be used as basic data for evaluating the exposure dose of operating workers for the construction of dry storage facilities in Korea.
The objective of this study is to identify the research trend in the field of indoor environment in Korea. We collected 419 papers published in the Journal of the Korean Society for indoor environment between 2004 and 2018, and attempted to produce datasets using a topic modeling technique, Latent Dirichlet Allocation(LDA). The result of topic modeling showed that 8 topics (“VOCs investigation”, “Subway environment”, “Building thermal environment”, “School health”, “Building particulate matter”, “Asbestos risk”, “Radon risk”, “Air cleaner and treatment”) could be extracted using Gibbs sampling method. In terms of topic trends, investigation of volatile organic compounds, subway environment, school health, and building particulate matter showed a decreasing tendency, while the building thermal environment, asbestos risk, radon risk, air cleaners, and air treatment showed an increasing tendency. The results of this topic modeling could help us to understand current trends related indoor environment, and provide valuable information in developing future research and policy frameworks.
본 연구에서는 수용성 접착제 가장 큰 단점인 내수성을 향상시킬 수 있는 수용성 첨가제를 개발하였다. 수 용성 첨가제는 diisocyanate 그룹을 가지는 분자들을 아황산수소나트륨과 반응시켜 얻을 수 있었다. FT-IR 측정 결 과 isocyanate 그룹이 완전히 사라진 것을 볼 수 있었고, DSC의 측정결과는 150℃ 이상의 온도에서 아황산수소나트 륨이 제거되어 isocyanate를 재형성하는 것을 확인할 수 있었다. 개발된 수용성 첨가제를 본사 제품인 DM-95 접착제 에 0.5 wt% 첨가하였을 때 높은 접착성능 및 향상된 내수성을 확보할 수 있었다. 그뿐만 아니라 기존의 복잡한 접착 공정을 요구하는 2 액형 시스템에서 탈피하여 생산 공정이 간단한 1 액형 시스템을 구축할 수 있으므로 산업 전반에 서 유용하게 사용될 것으로 사료된다.
The aim of this study was to evaluate different herbicides in corn-soybean intercropping for optimum growth, yield and nutritive value of forage under Korean environment conditions. Herbicidal treatments were randomly applied over five plots, viz. (1) Control treatment: no herbicide; (2) Alachlor; (3) Simazine; (4) Pendimethalin and (5) Mixture of alachlor and simazine herbicides in RCBD have three replications. Results depicted that treated herbicides exhibited significant effect over control of weeds. Simazine herbicide alone or mixed with alachlor had adverse effects on soybean but enhanced (p<0.05) corn production in terms of survivability, dry matter and digestible nutrients yield. Corn-soybean coupling and total dry matter yield were greater (p<0.05) in pendimethalin. Simazine-alachlor mixture reduced (p<0.05) soybean height. Conclusively, simazine could not be suitable for corn soybean intercropping because of having an adverse effect on soybean component. Pendimethalin could maintain growth and yield of corn and soybean both components. Effect of alachlor was comparable to that of pendimethalin.
Corn is basal forage for livestock species in Republic of Korea but it lacks protein and needs nitrogenous fertilizer. This study was designed with main objective to achieve optimum growth, yield & nutritive value of forage for livestock through implementing corn-soybean intercropping strategy at 17 different places under Korean condition. Two treatments; corn as monocrop (control treatment) and corn-soybean intercrop were compared under Randomized Block Design from 28th May to 8th October, 2015. Each treatment had three replicates in each block, whereas seventeen different places were considered as blocks. Data were analyzed through SAS-9.1.3 software. Difference between two treatment means was tested through T-test. Findings depicted that intercropping pattern could not influence (P>0.05) corn plant & ear height, corn lodged stalk No. and corn stalks number. However, corn-soybean intercropping enhanced (P<0.05) forage productivity in terms of total fresh yield (16.4±0.7b vs. 19.9±0.7a tons ha-1), total dry matter yield (5.38±0.25b vs. 6.41±0.31a tons ha-1) and total digestible nutrients yield (3.94±0.17b vs. 4.59±0.21a tons ha-1). Dry matter percentage in corn stalks and corn ears was not different (P>0.05) between two treatments. It was concluded that corn-soybean intercropping strategy was promising technique in enhancing forage productivity though positive symbiotic relation between two crops.
In attempt to avoid crop damage through wild bird’s picking, this study was designed with aim to evaluate several pre-sowing soybean seed coatings for optimum yield in corn-soybean mixed forage. It was investigated under four cropping treatments, viz. 1) corn sole, 2) corn mixed with soybean without any coating, 3) corn with iron coated soybean and 4) corn with thiram coated soybean. Each treatment had three replicates and corn sole was control treatment. Pioneer (P1184) and crossbred (PI483463 × Hutcheson) seeds were used for corn and soybean, respectively. The trial was conducted under randomized block design from 5th June to 23rd September, 2015. Data were an alyzed through ANOVA technique using SAS9.1.3 software. Results depicted that survivability of soybean against wild birds damage was found better (p<0.05) in thiram coating which was higher than iron coating and control treatment but later on thiram coating had adverse effects on subsequent growth of soybean plants. Corn stalk height was decreased (p<0.05) in thiram coating, whereas corn ear height was reduced in iron coating treatment. Iron coating enhanced (p<0.05) height of soybean plant (p<0.05) better than that of thiram coating. Soybean seed coatings didn’t influence dry matter yield and nutritive value in terms of total digestible nutrients yield in corn soybean mixed forage. Conclusively, although presowing thiram coating enhanced survivability of soybean plants against wild bird damage but had adverse effects on its subsequent growth. However, soybean seed coatings didn’t influence yield and nutritive value of corn soybean intercropping forage
다양한 질량비의 SiO2, Hollow SiO2 나노 파티클들을 Poly(methylmethacrylate) (PMMA) 용액에 분산하여 OLED 내부 광추출용 산란층을 제작 하였다. 구형의 실리카 나노 파티클들은 약 300 nm의 평균 입자 사이즈를 나타내었다. 실리카 나노 파티클 고분자 분산액은 스핀코팅을 통하여 기판위에 코팅 되어 제작되었다. 내부가 비어 있지 앉은 SiO2 나노 파티클 산란층의 경우 높은 산란 특성을 나타내었으며 (30wt%, 588 nm, Haze 0.37) Hollow SiO2 나 노 파티클의 경우 상대적으로 낮은 산란 특성을 나타내는 것을 확인할 수 있었다 (30 wt%, 588 nm, Haze 0.16). 하 지만 Hollow SiO2 나노 입자의 경우 매우 낮은 back-scattering으로 인한 높은 투과 특성을 나타내었다 (30 wt%, 588 nm, 85%). 또한 입자의 함량 증가에 따른 투과도의 감소와 산란의 증가 비가 상대적으로 매우 높음을 확인할 수 있었다.
유기 발광 다이오드(OLED)는 차세대 조명으로 많은 관심을 받고 있으며, 디스플레이로서의 상용화에 이미 성공하였고, 대체 조명 시장에까지 그 영역을 넓혀가고 있다. OLED의 급격한 기술 발전에도 불구하고, OLED의 유 기층/투명전극과 기판에서 발생하는 내부 전반사에 의해서 일반적인 OLED의 외부 광자 효율은 현재 20~30% 정도에 머무르고 있는 실정이다. 따라서, 고효율의 OLED의 구현을 위해서는 고성능의 광추출 구조의 개발이 절실히 필요하 다. 내부 광추출 구조를 소자에 적용하기 위해서는 많은 어려움이 있으며, 특히 소자의 누설전류를 방지하기 위해서 광추출 구조의 표면 거칠기를 최소화하는 것이 매우 중요하다. 본 연구에서는 ZnO 나노파티클-투명 고분자 복합 구 조의 광추출 구조를 쉬운 제작 방법으로 구현하였으며, 나노파티클의 분산에 따른 광추출 구조의 광학적 특성 및 표 면 구조의 영향에 대해서 알아보았다.
The population of managed honey bees has been dramatically declining the recent past in worldwide. The one of most common disease of bees is nosemosis, the nosemosis is caused by microsporidia in the genus Nosema. Nosema apis and N. ceranae have been described as honeybee pathogens. These microsporidia are highly evoloved fungi with an obligately intracellular parasitic lifstyle. The disease causes significant detriment to honey production and results in economic losses. In our knowledge, Fumagillin is the only antibiotic approved for control of nosemosis in honey bees, however this antibiotic may have unintended effects on the honey bee host, ultimately contributing to increased prevalence and pathogenicity of Nosema. Therefore, we screened anti-Nosema substances from entomopathogenic fungal culture filtrates using in vitro polar tube germination assay. These fungal metabolites are employed as antibiotic agents. As results, Total 3 samples (23% of 13 total samples) showing the germinating inhibition against N. ceranae. This screening method may be useful for the detection of anti-Nosema substances from various samples and selected samples in this study may be a good feature to be used in the development of a new biocontrol method of nosemosis.
고 종횡비 MEMS 구조물의 습식 공정에서 세정 이후 건조 과정에서 발생하는 문제점들을 극복하기 위하여 초임계 이산화탄소를 이용한 고 종횡비의 MEMS 구조물의 건조방법에 대하여 조사하였다. 실험에 사용된 MEMS 구조물 습식 제조방법의 세정은 HF/water에서 식각된 cantilever beam을 isopropyl alcohol (IPA)로 치환하여 진행되었다. 초임계 이산화탄소에 의한 IPA의 제거율은 VOC 분석법을 통하여 다양한 조건에서 측정 되었고, 건조된 cantilever beam은 SEM을 이용하여 관찰하였다. 자연 건조를 통한 방법으로는 종횡비 1:15의 cantilever beam까지 stiction 없이 제조할 수 있었으나, 초임계 이산화탄소를 이용한 MEMS 구조물의 건조는 기존의 건조방법 보다 고 종횡비를 가지는 1:75의
cantilever beam까지 stiction 없이 제작할 수 있었다.
The aim of the study is to report Radopholus similis detected from Agathis dammara in Thailand as new host plant. Existing host of R. similis was known as coffee, pepper, sugarcane and banana etc. This nematode in this study was observed morphologic character using Carl Zeiss Axioimager M2 and Axiovision Rel. 4.8 program. The result shows that a and b of the female was distorted toward maximum value of original description of species, and b′, c and stylet length was distorted toward minimum value of original description of species. This nematode was morphologically distinguished from originally detected R. similis, but measured value was similar in range of original description of species. For more information, molecular assay was also confirmed the R. similis with 98% homology with the sequence of the internal transcribed spacer region (ITS) of ribosomal DNA. We provided PCR-amplified ITS nucleotide sequence.
Most patients with chronic low back pain experience functional disability of trunk muscle, and limitations in physical activity. While there are many types of exercise programs available, in recent years sling exercise has been emerging as the exercise program for spinal stabilization. It has been supported by a great amount of research with positive findings on its effectiveness. This research studies the effects of bridging exercise, conducted on a sling, on pain level and trunk muscle activation in supine, sidelying, and prone positions during a 4 weeks period. 10 healthy people(normal group, n=10) and 28 patients with low back pain participated in this study. 28 patients were divided into two groups; one group participated in exercise with the sling(experimental group, n=14) and the other group exercised without the sling(control group, n=14). They were asked to use the Numerical Rating Scale(NRS) to answer to the level of their pain they felt (no pain: 0 point, severe pain: 10 points). During sling bridging exercises, the muscle activity level in each muscle measured in each position was standardized as three seconds of EMG signals during five seconds MVIC. In conclusion, the experimental group with four weeks of sling bridging exercise experienced a statistically significant reduction in the pain level(p<.05) and increase in the muscle activities of erector spinae when in supine position, internal oblique when in sidelying position, and rectus abdominis in prone position(p<.05). Regular sling bridging exercise reduces the low back pain and enhances other trunk muscle activation, thereby positively affect spinal stabilization.