Blockchain is an immutable ledger that records transactions and tracks assets using a common communication protocol. It stores a copy of the blockchain and implements a consensus function to verify transactions. Blockchain is applied to industries beyond finance, such as retail, to maintain security and transparency. Consumers with knowledge of blockchain technology are likely to be affected when evaluating products with blockchain embedded, impacting their product evaluation. The study investigates the impact of blockchain technology on consumers' product evaluation and how knowledge of blockchain and product quality moderate its effects.
At high temperatures, molten salt has heat transfer properties like water. Molten salt has the characteristics of a strong natural circulation tendency, large heat capacity, and low thermal conductivity. Unlike sodium, molten salt does not react explosively exothermically with air. However, molten salt has a strong tendency to corrode materials, and its properties are easily changed by a sensitive reaction to oxygen and moisture. Therefore, it is necessary to study material corrosion properties and chemical control methods for nuclear fuel salts, which are eutectic mixtures. In this study, the optimal operation method of the thermal convection loop is established to perform the experiments on the molten salt. The process describes briefly as follows. The operation step consists of preparation, purification, transportation, and operation. In the preparation, the step checks the entire structure and equipment (TC, blower, vacuum pump, etc.). And melt the salt mixture at a high temperature (670°C) slowly in the purification step. Before injecting the molten salt, the surface temperature of the entire loop must retain temperature (about 500°C) constantly. Completely melted molten salt in the melting pot is flow along the pipe of the thermal convection loop in the transportation step. Lastly, the convection of molten salt goes to keep by the temperature difference. The thermal convection loop can be utilized for various experiments such as corrosion tests, component analyses, chemistry control, etc.
Molten salt used in the multipurpose molten salt experiment must be of high purity. Depending on the purpose of the experiment, only the base component of the molten salt be used, or a component simulating a nuclear fission product be added to the base component and used. In all cases, an increase in the concentration of impurities such as oxygen and moisture may lead to an erroneous interpretation when analyzing the experimental results. Therefore, molten salt should be purified before use. In this study, the purification of molten salt is described for multi-purpose molten salt experiments. The salt mixture is selected as MgCl2-NaCl and is quantified at a mixing ratio of 43mol%:57mol%. The salt mixture is treated in a glove box environment because of must minimize the reaction of adsorbing oxygen and moisture when the salt mixture is exposed to the atmosphere. MgCl2 is more likely to contain water than NaCl, the purification of the NaCl-MgCl2 mixture is established according to the purification process for removing water from MgCl2. A process for purifying the salt mixture briefly consists as follows: drying moisture, melting salts, purification, removing HCl, and stabilization. Through the process be able to obtain high-purity molten salt and more accurate experiment results.
위치 기반 AR 게임에서 모바일 기기의 위치를 정확하게 추정하는 것은 중요한 요소 중 하나이다. 모바일 기 기에 내장되어 있는 위치 추정 시스템이 얼마나 정확하게 위치정보를 추정하는 지가 증강되는 AR 콘텐츠의 정확도를 결정한다. 하지만 도시 환경에서는 건물, 건축물, 광고판, 표지판 등 지형지물 및 장애물에 의해서 위치 추정을 위해 필요한 신호가 반사, 굴절, 회절, 차단 등이 발생하게 되고 그로 인하여 모바일 기기의 위 치 추정 시스템으로부터 추정되는 위치에 오차가 생기게 된다. 본 논문에서는 도시 환경에서 모바일 기기의 위치 오차가 증가하는 현상에 대해서 상용 스트리트 뷰와 문자 태그를 활용하여 심플하면서도 신뢰성 있는 위치 보정 방안을 제안한다. 제안하는 위치 보정 방안은 쿼리 이미지와 스트리트 뷰 파노라마 이미지로부터 생성된 문자 태그를 대조하는 것을 통해서 매칭 스코어를 계산한고 매칭 스코어에 따라 쿼리 이미지를 촬영 한 실제 위치와 가까운 스트리트 뷰를 검색하는 것을 통해서 모바일 기기의 위치를 보정한다. 제안하는 위치 보정 방안은 위치 오차가 43.71m인 위치를 위치 오차가 4.09m인 위치로 보정하였으며 낮과 밤에 관계없이 위치를 보정할 수 있다는 장점이 있다.
세라마이드는 일반적으로 화장품 산업에서 피부의 보습 및 피부장벽강화에 도움을 주는 성분으로 많은 연구와 개발이 활발하게 이루어지고 있다. 이번 연구에서는 일반적인 합성 세라마이드가 아닌 달맞이꽃오일에서 얻은 천연 세라마이드를 함유한 보습크림이 피부의 보습 및 경피수분손실량의 변화에 어떤 영향을 미치는지를 확인하였다. 세라마이드를 함유한 보습크림이 세라마이드들 함유하지 않은 보습크림과 비교하여 피부보습력과 경피수분손실량에서 우수한 결과 값을 나타내었음을 확인하였다.
애기유리나방의 성페로몬인 Z,Z-3,13-octadecadien-1-ol (Z3,Z13-18:OH)을 이용한 교미교란 효과를 검증하기 위하여 경남(진주)과 전남(순천)의 단감원에서 2016년부터 2년간 실험을 하였다. 2016년에는 순천과 진주A, 진주B의 세 단감원에 성페로몬 5 ㎎/septum을 각 나무마다 한 개씩 처리하여 교미교란 효과를 확인하였다. 그 결과, 순천과 진주A 과수원에서는 100 %의 교미교란 효과를 나타내었지만 진주B 과수원에서는 효과가 전혀 없었다. 2015년과 2016년 같은 기간에 애기유리나방의 밀도를 조사 결과 진주A 과수원에 비해 진주B 과수원의 애기유리나방 밀도가 약 6.7배 많은 것을 확인 할 수 있었다. 그리하여 2017년 제1화기 때에 진주B 과수원에서 성페로몬 량을 10 ㎎/septum로 늘려서 실험한 결과 교미교란 효과가 66.7%로 낮았다. 2017 2화기 때에 다시 진주A 과수원으로 장소를 옮겨 실험한 결과 100 %의 교미교란 효과가 있는 것을 확인하였다. 이러한 결과로 보아 교미교란 효과는 페로몬 량 뿐 아니라 지형의 영향도 받는 것으로 판단된다.
Azuki bean beetle (ABB), Callosobruchus chinensis (L.) is a field-to-storage pest of legumes. It is ideal to estimate its field population before it invades the stored legume stuffs. The seasonal occurrence was monitored with rocket traps supplied with synthetic female sex pheromone and with sweep netting during 2015-2016. Harvest damage was evaluated by taking purposive samples of the pods at harvest. Over-wintering stage was identified from the pod samples of left over plants. The results ascertained that October was the peak season of ABB in the azuki bean field. Grain damage and weight loss of the harvested azuki bean were 2.7% and 2.4% respectively, which could be the inoculum for storage loss. The adult emergence only from live pupae collected from pods revealed for its most probable over-wintering stage. In all, this study provides insight into some field ecological parameters of ABB that could be helpful in adopting its management strategies.
Plant essential oils (EOs) exhibit an array of biological activities against insect pests. However, their negative influences on the pheromonal activity of azuki bean beetle (ABB), Callosobruchus chinensis L., the field-to-storage pest of legumes, have not received research attentions. We evaluated the effects of three EOs and their two major components on the attractiveness of male ABBS to synthetic homofarnesal (2E- : 2Z-homofarnesal = 6:4) using Y-tube olfactometry in laboratory and rocket traps in the semi-open vinyl house. The tested EOs of Illicium verum, Croton anisatum and Gaultheria fragrantissima as well as the major components, trans-anethole and methyl salicylate ascertained significant negative effect against homofarnesal both in Y-tube olfactometry and in semi-open vinyl house tracing out a new opportunity of integrating them in ABB management programs both in field and storage.
본 연구는 국내 유통되고 있는 건조 농산물 중 33종의 고구마말랭이에 대하여 이산화황, 카로티노이드 함량 및 바실러스 세레우스 오염 정도를 조사하였다. 고구마말랭이의 시료별 특징에 따라 4가지의 군집으로 분류하여 각 군집간의 이산화황, 카로티노이드 함량 및 바실러스 세레 우스 함량을 조사한 결과, 각 군집간의 유의적인 차이는 나타나지 않았다. 33개의 고구마말랭이에서 잔류 이산화 황이 검출 범위는 0.38~28.16 mg/kg으로 기준인 10 mg/kg 이상으로 검출된 경우는 3건(9.09%) 이었지만, 고구마말 랭이의 이산화황 잔류 허용 기준치인 30 mg/kg을 초과하는 시료는 나타나지 않았다. 고구마말랭이는 카로티노이드에 대한 규격 기준이 없으므로 카로티노이드의 국·내 외 기준을 비교하였을 때, 본 실험에서 검출된 고구마말랭이의 카로티노이드 검출 범위는 46~2663 μg/100 g 로 카로티노이드의 함량 기준인 0~9,826 μg/100 g 의 범위 내로 확인되었다. 고구마말랭이 시료에서 바실러스 세레우스로 추정되는 집락은 대체적으로 검출되지 않았으며 7건(21.21%) 에서만 0.05~1.59 log CFU/g 범위로 검출되었지만 국내 기준치인 3 log CFU/g 은 넘지 않는 것으로 확인되었다. 본 연구결과는 건조 농산물 중 고구마말랭이에 대한 기준규 격 제정 시 품질 지표 기준으로 설정할 수 있는 기초자료 로서 활용될 것으로 판단되며 국내 유통중인 고구마말랭 이에 대한 품질 관리를 위해서는 원재료부터 건조 방법 그리고 포장 후 유통까지 안정하게 공정 과정이 진행되도 록 지속적인 관리 및 유지를 해야 될 것으로 사료된다.
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.
The entomopathogenic fungus Metarhizium anisopliae is one of potent biological control agents against a variety ofinsect pests. In this study, we investigated enzyme production of M. anisopliae strains A and B. They produced extracellularenzymes for degrading the epidermis of Monochamus alternatus, a crucial mediator of the pinewood nematode Bursaphelenchusxylophilus. With Q-TOF MS/MS analysis, 29 kDa protein, a major band on a SDS-PAGE gel, was identified as subtilisin-likeserine protease PR1A. M. anisopliae A produced an extracellular enzyme more efficiently than M. anisopliae B: however,enzyme activities targeted for the cuticle were comparable. Our results suggest that the two strains of M. anisopliae havethe biological potential against M. alternatus with insecticidal protease production.
Euzophera batangensis (Lepidotera: Pyralidae) is seriously damaging trunks or branches of persimmon tree (Diospyros sp.). We tested the attractiveness of (Z)-9-tetradecen-1-ol (Z9-14OH) and (Z9,E12)-tetradeca- 9,12-dien-1-ol (Z9,E12-14OH) with single or blended baits at southern parts of Korea in 2014 and 2015. The monoene was not attractive at all at three places during the two years. In 2014, diene was equally or more attractive than the mixture in Jinju and Suncheon, respectively. In 2015 too, the attractiveness of diene and mixture was not different in Jinju and Munsan. Monitoring of the seasonal occurrence of E. batangesis with the sex pheromone components revealed that it occurred three times a year; the first occurrence from early April to mid May, the second from early Jun to mid July, and the third from late August to late September.
Chitin synthase (CHS) is an important enzymatic component, which is required for chitin formation in the cuticles and cuticular linings of other tissues in insects. CHSs have been divided into two classes, class A and B, based on their amino acid sequence similarities and functions. Class A CHS (CHS-A) is specifically expressed in the epidermis and related ectodermal cells such as tracheal cells, while expression of class B CHS (CHS-B) is expressed in gut epithelial cells that produce peritrophic matrices. In this study, we cloned the CHS-A gene from the beet armyworm, Spodoptera exigua. The SeCHS-A mRNA was expressed in all developmental stages and specifically in the epidermis and tracheae tissue by RT-PCR analysis. Expression of SeCHS-A gene was suppressed by feeding double-stranded RNA (dsRNASeCHS-A, 150 ng/larva) in the fifth instar of S. exigua. The suppression of SeCHS-A gene expression significantly induced mortality on pupal stage. Also, larvae fed with dsRNASeCHS-A significantly enhanced pathogenicity of an entomopathogenic fungus, Beauveria bassiana ANU1. These results suggest that the SeCHS-A gene plays an important role in development of S. exigua and dsRNA, which is a specific to SeCHS-A gene, may be applied to effective pest control with B. bassiana.
Oxalic acid has a nematicidal activity against the root-knot nematode Meloidogyne incognita. High producer of oxalic acid was isolated, and then named as Aspergillus niger F22. Oxalic acid production was investigated under various temperatures from 20 – 33oC and rotational speeds in 5 L jar fermenters. Yield of oxalic acid increased with decreasing temperature. The highest yield was obtained at 23oC, showing the yield of oxalic acid of 8.7 g/L, whereas oxalic acid production was least at 33oC. At 20oC, the yield was lower than that of 23oC. At a rotational speed of 300 rpm, serious oxygen depletion was present from 48 - 72 h, resulting in low productivity of 26.2 mg /L·h. When a rotational speed was set at 600 rpm, dissolved oxygen tension was over 40% and oxalic acid production increased up to approximately 55%. Viscosity during the culture differed with temperatures. Viscosity increased with the increment of temperatures. When A. niger F22 was cultured at 23oC, viscosity was 810 cP, which was favorable for oxalic acid production.