계란의 비린내 강도는 가금류의 종류와 개인의 인식에 따라 다르지만 여러 요인에 의해 발생할 수 있다. 특히 트 리메틸아민(TMA)이 원인으로 밝혀졌다. 주목할만한 점은 리보플라빈이 TMA를 무취의 트리메틸아민-N-옥사이드로 전환시키는 역할을 하는 효소인 플라빈 함유 모노옥시게 나제 3의 활성을 증가시킬 수 있다는 점이다. 본 연구는 난황의 TMA 함량을 분석하여 비린내에 대한 기여도를 평 가하고, 비린내를 방지하는 방법을 개발하는 것을 목적으 로 하였다. 고체상 미세추출-기체 크로마토그래피/질량 분 석법을 사용하여 리보플라빈이 강화, 보충된 사료를 먹인 암탉의 난황에 있는 휘발성 화합물을 감지하고 정량화했다. 또한 샘플 간 휘발성 물질의 상대적 함량을 비교하기 위해 전자코를 이용하여 상관관계 연구를 수행하였다. TMA는 콜린이 함유된사료를 섭취한 가금류의 난황에서 고농도로 검출되었지만 리보플라빈이 보충된 사료를 섭취한 가금류 에서는 검출되지 않았다. 전반적으로, 이 연구는 리보플라 빈이 TMA를 포함하여 계란에 존재하는 휘발성 물질의 양 과 품질에 영향을 미친다는 것을 시사한다. 이러한 발견 이 계란의 비린내를 줄이는 것은 물론 품질 향상에 기여 하기를 기대한다.

For transport containers for radioactive wastes, a drop test should be performed at a height of 0.3– 1.2 m on a rigid target depending on the weight as a normal condition in the regulation. In the drop test, a strain gauge is commonly used to measure the local strain, and the position of the strain gauges is determined by the experiences of the engineer in advance of the test. For this reason, the strains can be measured at only predetermined points. The DIC (Digital Image Correlation) method using highspeed cameras can be used to measure the change in strain over the region of interest. In addition, it is possible to measure effectively even in areas with high strain gradients that are difficult to measure with strain gauges. Therefore, the DIC method can measure the strain change according to time over the entire load path. When the drop test of the transport container is performed, the impact load is delivered through the lower corner fittings-corner posts-upper corner fittings-lids. In this study, white spray was sprayed on these main load path, and black speckles were created on the spayed surface to trace the rigid motion of speckles. The images taken during the drop test can be used to create a strain field over region of interest.

The bacterial soft-rot disease is one of the most critical diseases in vegetables such as Chinese cabbage. The researchers isolated two bacteria (Pseudomonas kribbensis and Pantoea vagans) from diseased tissue samples of Chinese cabbages and confirmed them as being the strains that cause soft-rot disease. Lactic-acid bacteria (LAB), were screened and used to control soft-rot disease bacteria. The researchers tested the treatments with hypochlorous acid water (HAW) and LAB supernatant to control soft-rot disease bacteria. The tests confirmed that treatments with the HAW (over 120 ppm) or LAB (Lactobacillus plantarum PL203) culture supernatants (0.5 mL) completely controlled both P. kribbensis and P. vagans.

본 연구에서는 국내산 돌미나리에서 GABA생성능이 있 는 신규 유산균을 분리, 동정한 결과, Enteroccoccus casseliflavus로 확인되었다. 최근까지 Lactobacillus속과 같 은 GABA 생성 유산균에 대한 보고는 많이 되고 있고, 일 부 Enterococcs속 유산균도 보고되고 있으나 E. casseliflavus 종에 대한 보고는 없었다. 따라서 본 연구에서는 E. casseliflavus PL05 균주에 대한 GABA 생성 최적 조건을 찾기 위하여 배지의 유형, 생육 온도, 초기 pH 조건, 배양 시간, MGS 농도 및 탄소원을 포함한 다양한 조건을 테스 트하였다. PL05 균주는 MRS 혹은 TSB 배지보다 BHI 배 지에서 생육이 잘 되었으며, 배지의 초기 pH는 7-9 조건 에서 가장 생육이 왕성하였고, GABA 생성 조건 역시 유 사한 결과로 확인되었다. GABA의 기질에 해당하는 MSG 의 농도별 GABA 생성량을 조사한 결과, 7%에서 가장 높 은 생성량을 나타내었으나 5%에서도 유사한 수준으로 확 인되어 효율적인 측면에서 5%가 적합할 것으로 판단된다. 탄소원에 따른 생육 및 GABA 생성량은 말토오스를 사용 하였을 때 가장 높은 것으로 확인되었고, 이러한 최적의 조건들로 최종 테스트를 진행한 결과, 24시간째 140.06±0.71 mM의 GABA가 생성되었고, 전환율은 78.95%로 확인되 었다. 또한 반코마이신을 포함한 10개의 항생제에 대한 감 수성을 조사한 결과 내성이 없는 것을 확인하였다.

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.

As the number of North Korean refugees increases in South Korean, their acculturation to life in their host country is coming to be an important social issue. This study explores some clothing-related barriers experienced by North Korean refugees and their moderating effects on acculturation to South Korea. Data were collected using a self-administered survey of 163 female and 37 male North Korean refugees in South Korea aged 20 to 69 years. Descriptive analyses, t-tests, ANOVA, Duncan tests, and moderated multiple regression were conducted using SPSS 20.0 and Process Macro v.3.3. The results show that the North Korean refugees who participated in the study had experienced clothing-related barriers regarding fashion terminology and shopping rituals in South Korea. In particular, those in their 60s perceived more clothing-related barriers than those in their 20s and 30s. Next, the clothing-related barriers experienced by North Korean refugees have a negative moderating influence on the relationship between self-esteem and acculturation in South Korea. This study provides a deeper understanding of the relationship between fashion and the acculturation of North Korean refugees to South Korea. The results of the study can be also helpful of government policy makers, practitioners, and academics to develop education programs for North Korean refugees.

In this study, epoxy composites were reinforced with multi-walled carbon nanotubes and fused silica particles, dispersing the fillers within the epoxy resin based on a simple physical method using only shear mixing and ultrasonication. The hybrid composite specimens with 0.6 wt% of carbon nanotubes and 50 wt% of silica particles showed improved mechanical properties, with increase in tensile strength and Young’s modulus up to 12 and 37%, respectively, with respect to those of the baseline specimens. The experimental results showed that the low thermal expansion of the silica particles improved the thermal stability of the composites compared with that of the baseline specimen, whereas the thermal expansion slightly increased, due to the increased heat transfer from the exterior to the interior of specimens by the carbon nanotube filler. The coefficient of thermal expansion of the hybrid composite specimen reinforced with 0.6 wt% of carbon nanotubes and 50 wt% of silica particles was decreased by 25%, and the thermal conductivity was increased by about 84%, compared with those of the baseline specimen.

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.

Pesticide application in agriculture provides significant benefits such as protection from disease, prevention of harmful insects, and increased crop yields. However, accurate toxicological tests and risk assessments are necessary because of many related adverse effects associated with pesticide use. In this review, we discuss and analyze residual pesticides contained in livestock feed in Korea. A pesticide residue tolerance standard for livestock feed has not been precisely established; so, risk assessments are required to ensure safety. Standards and approaches for animal criteria and appropriate methods for evaluating residual pesticides are discussed and analyzed based on technology related to animal product safety in Korea. The safety of livestock feed containing pesticides is assessed to establish maximum residue limits relative to pesticides. Analysis of residual pesticides in milk, muscle, brain, and fat was performed with a livestock residue test and safety evaluation of the detected pesticide was performed. Efficacy of organic solvent extraction and clean-up of feed was verified, and suitability of the instrument was examined to establish if they are effective, rapid, and safe. This review discussed extensively how pesticide residue tolerance in livestock feed and hazard evaluation may be applied in future studies.

Biofilms of oral microbes can cause various diseases in the oral cavity, such as dental caries, periodontitis and mucosal disease. Electrolyzed water generated by an electric current passed via water using a metal electrode has an antimicrobial effect on pathogenic bacteria which cause food poisoning. This study investigated the antimicrobial activity of electrolyzed waters using various metal electrodes on the floatage and biofilms of oral microbes. The electrolyzed water was generated by passing electric current using copper, silver and platinum electrodes. The electrolyzed water has a neutral pH. Streptococcus mutans, Porphyromonas gingivalis and Tannerella forsythia were cultured, and were used to form a biofilm using specific media. The floatage and biofilm of the microbes were then treated with the electrolyzed water. The electrolyzed water using platinum electrode (EWP) exhibited strong antimicrobial activity against the floatage and biofilm of the oral microbes. However, the electrolyzed water using copper and silver electrodes had no effect. The EWP disrupted the biofilm of oral microbes, except the S. mutans biofilm. Comparing the different electrolyzed waters that we created the platinum electrode generated water may be an ideal candidate for prevention of dental caries and periodontitis.

Explicit environmental attitude measures tend to produce strong socially desirable responses (Bruni & Schultz, 2010; Milfont & Duckitt, 2010; Stern & Dietz, 1994) and fail to capture more than what participants consciously recall (e.g., explicit belief, past behavior, Dunlap, Van Liere, Mertig, Jones, 2000; Schultz, Shriver, Tabanico, & Khazian, 2004). A number of studies have highlighted the popularity of environmental issues in common discourse in various countries, which leads individuals to eagerly express pro-environmental explicit attitudes (Dunlap, 1998; Leiserowitz, 2005; Meijers & Stapel, 2011). Therefore, an explicit measure of environmental attitudes would hardly be an unbiased indicator of prior knowledge and experience when testing the effect of subtle feeling on judgments: although a participant explicitly reports favorable attitudes toward environment or related issues, it does not necessarily mean that she or he has knowledge and experience to hinder the regulatory fit effects. Using the Implicit Association Test, we examined whether the extent to which individuals are implicitly biased toward (or against) sustainability moderates the regulatory focus by construal level interaction. Scores from the indirect measure of attitudes served as the indicator of the strength of associations between the concept of sustainability and evaluations that may result form its frequent pairing with desirable consumption patterns or repeated exposure to persuasive messages promoting sustainability. Specifically, we showed that the regulatory focus – construal level fit effect will be greater among individuals who have not formed significant associations about sustainability since these individuals are more likely to rely on feeling right from regulatory fit rather than using prior experience or knowledge.

절삭가공에서 가공양의 과다 및 가공부위와 형상은 절삭저항에 의한 절삭 열을 발생시키고 이 열로 인해 가공품의 정밀도에 변형을 가져온다. 절삭가공 시 공작기계에서 발생하는 오차의 40~70%는 열 변형 오차에 의해서 발생한다. 박판 박판 블레이드는 절삭 열을 받아들이는 공작물의 두께가 얇기 때문에 열 변형 오차에 쉽게 정밀도가 저하된다. 이때에 뒤틀림이 발생하면 정밀도는 매우 큰 오차를 포함하게 된다. 본 연구의 목적은 박판의 절삭가공에서 열 변형이 발생함을 예측하고 발생 부위에 따라 어떤 변형이 발생하는 지를 측정하여 파악하고자 한다. 또한, 측정된 결과를 통해 열 변형을 최소화하는 가공방법을 제시한다.

Basic creep in concrete at an early age plays an important role in the mechancal properties of young concrete and many researches on this field have been carried out. According to recent some studies, however, it is the conclusion that for some cases the basic creep measured from the sealed concrete specimen shows inaccurate results. More specifically, for high-strength concrete (HSC), the incorrectness is more apparent due to autogenous shrinkage occurred at an early age. This paper shows the results obtained from experimental study to evaluate the effect of autogenous shrinkage on basic creep. In this study, four different mixture proportions of which primany test variable is water-cement ratio (w/c) were placed and autogenous shrinkage and basic creep tests on the specimen were performed with age and various loading levels. From this research, it was found that the differences between apparent creep and real creep were remarkable in HSC at an early age. Therefore, it is recommended to modify existing basic creep model equation by considering autogenous shrinkage.

This study examined the effects of startup firm's knowledge assets on the effectiveness of their sales strategies, efficiency of sales activities, and management performance, after categorizing these assets into customer knowledge assets and technology knowledge assets. Furthermore, the moderating effects of promotion focus by CEOs and sales managers of startup firms were analyzed. For the analysis, dyadic questionnaire surveys were conducted targeting the CEOs and sales managers of startup firms established at the Gyeongnam Technopark and the KAIST Technology Business Incubation Center in Korea. Hypotheses were verified through structural equation modeling, and moderating effects were identified through ANOVA. CEO's customer knowledge asset strengthened their effectiveness of sales strategies, and sales manager's technology knowledge asset strengthened the efficiency of their sales activities. Also, CEO's effectiveness of sales strategies and sales manager's efficiency of sales activities have been found to enhance startup firm's management performance. Meanwhile, the moderating effect of promotion focus strengthened CEO's effectiveness of sales strategies through CEO's customer knowledge asset and interaction as CEO's promotion focus level increased, but promotion focus of sales managers did not have any significant interaction effect. This study provides implications by offering empirical evidence on startup firms with regard to knowledge assets.