• Title/Summary/Keyword: model organism

Search Result 243, Processing Time 0.026 seconds

Microbiological Safety Concerns with Dairy Products from Farmstead Plants (목장형 유가공업의 미생물학적 안전성에 대한 고찰)

  • Lee, Jeeyeon;Yoon, Yohan
    • Journal of Dairy Science and Biotechnology
    • /
    • v.35 no.4
    • /
    • pp.215-220
    • /
    • 2017
  • The consumption of natural cheese in Korea has dramatically increased since 1997. However, most of the cheeses consumed in Korea are imported. Thus, surplus milk has accumulated in Korea. To solve this problem, the Ministry of Agriculture, Food and Rural Affairs established a policy to create a farmstead dairy industry. Although the law governing the industry was established in 2016, food safety guidelines have not been prepared. Milk and cheese are prone to contamination with mycotoxins such as aflatoxin M1 and ochratoxin A, antibiotic residues such as penicillin and tetracycline, and pathogenic bacteria including Listeria monocytogenes, Escherichia coli, Salmonella, and Staphylococcus aureus. L. monocytogenes infections have a very high mortality rate; hence, special attention should be paid to preventing contamination of milk and cheese with this organism. To ensure the microbiological safety of farmstead dairy products, the HACCP model has been used. However, this model is not suitable for current processing environments of farmstead dairy products because of the small size of the operations. In addition, scientific data on the microbiological safety of farmstead dairy product are limited and are urgently needed.

ABSORBED INTERNAL DOSE CONVERSION COEFFICIENTS FOR DOMESTIC REFERENCE ANIMALS AND PLANT

  • Keum, Dong-Kwon;Jun, In;Lim, Kwang-Muk;Choi, Yong-Ho
    • Nuclear Engineering and Technology
    • /
    • v.42 no.1
    • /
    • pp.89-96
    • /
    • 2010
  • This paper describes the methodology of calculating the internal dose conversion coefficient in order to assess the radiological impact on non-human species. This paper also presents the internal dose conversion coefficients of 25 radionuclides ($^3H,\;^7Be,\;^{14}C,\;^{40}K,\;^{51}Cr,\;^{54}Mn,\;^{59}Fe,\;^{58}Co,\;^{60}Co,\;^{65}Zn,\;^{90}Sr,\;^{95}Nb,\;^{99}Tc,\;^{106}Ru,\;^{129}I,\;^{131}I,\;^{136}Cs,\;^{137}Cs,\;^{140}Ba,\;^{140}La,\;^{144}Ce,\;^{238}U,\;^{239}Pu,\;^{240}Pu$) for domestic seven reference animals (roe deer, rat, frog, snake, Chinese minnow, bee, and earthworm) and one reference plant (pine tree). The uniform isotropic model was applied in order to calculate the internal dose conversion coefficients. The calculated internal dose conversion coefficient (${\mu}Gyd^{-1}$ per $Bqkg^{-1}$) ranged from $10^{-6}$ to $10^{-2}$ according to the type of radionuclides and organisms studied. It turns out that the internal does conversion coefficient was higher for alpha radionuclides, such as $^{238}U,\;^{239}Pu$, and $^{240}Pu$, and for large organisms, such as roe deer and pine tree. The internal dose conversion coefficients of $^{239}U,\;^{240}Pu,\;^{238}U,\;^{14}C,\;^3H$, and $^{99}Tc$ were independent of the organism.

Effects of Information Quality of Online Travel Agencies on Trust and Continuous Usage Intention: An Application of the SOR Model

  • LEE, Seul Ki;MIN, So Ra
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.8 no.4
    • /
    • pp.971-982
    • /
    • 2021
  • The purpose of this study was to investigate the relationship between information quality, Online Travel Agency (OTA) trust, and continuous usage intention provided by OTA through the application of the SOR(Stimulus-Organism-Response) model. To achieve the purpose of the study, 234 responses were used for analysis, and the hypotheses were tested through the SPSS v.21 program and AMOS v.21 programs. The research results can be classified into the following three categories. First, it was determined that accuracy, timeliness, and usefulness among the factors for information quality had a significant positive effect on OTA trust and continuous usage intention. Second, it was determined that OTA trust was found to have a significant positive effect on continuous usage intention. Third, it was determined that OTA trust had an indirect effect on the relationship between accuracy, timeliness, usefulness, and continuous usage intention among the factors for information quality. This study looked at the lower dimension of information quality, which was insufficient in the field of OTA. This study can be used as basic data to, in practice, build a user-centered informational provision environment by identifying the factors that promote the continuous usage intention of consumers, which is linked to the revenue of online travel agencies.

Study of User Reuse Intention for Gamified Interactive Movies upon Flow Experience

  • Han, Zhe;Lee, Hyun-Seok
    • Journal of Multimedia Information System
    • /
    • v.7 no.4
    • /
    • pp.281-293
    • /
    • 2020
  • As Christine Daley suggested, "interaction-image" is considered to be typical in the age of "Cinema 3.0", which integrates the interactivity of game art and obscures the boundary between producers and customers. In this case, users are allowed to involve actively in the scene as "players" to manage the tempo of the story to some extent, it, thus, makes users pleased to watch interactive movies repeatedly for trying a diverse option to unlock more branch lines. Accordingly, this paper aims to analyze the contributory factors and effect mechanism of users' reuse intention for gamified interactive movies and offer specific concepts to improve the reuse intention from the interactive film production and operation perspectives. Upon integrating the Flow theory and Technology Acceptance Model (TAM) and separating the intrinsic and extrinsic motivations of key factors based on Stimulus-Organism-Response (S-O-R), the research builds an empirical analysis model for users' reuse intention with cognition, design, attitude emotional experience and conducts an empirical analysis on 425 pieces of valid sample data applying SPSS22 and Amos23. The results show that user satisfaction and flow experience impact users' reuse intention highly and perceived usefulness, perceived ease of use, perceived enjoyment, remote perception, interactivity, and flow experience have significant positive influence on user satisfaction experience.

Moderated Mediation of Anticipatory Hope between Green Fashion Advertising Appeals and Word of Mouth -The Role of Perceived Consumer Effectiveness-

  • Choi, Dooyoung;Lee, Ha Kyung
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.46 no.3
    • /
    • pp.513-529
    • /
    • 2022
  • Based on the stimulus-organism-response model, this study investigated the effects of three types of green performance appeals (i.e., before-, after-, and before/after-appeals) on consumer word of mouth (WOM) mediated by anticipatory hope. As the degree of consumer susceptibility to advertising varies by individual, individual perceived consumer effectiveness (PCE) was examined as a moderated mediating variable. A total of 191 responses were analyzed using SPSS 27.0 for analysis of variance and PROCESS procedure. Results showed the mediating role of anticipatory hope between advertising appeals and WOM: participants reported greater anticipatory hope when they viewed the advertisement with after- and before/after-appeals. This mediation was moderated by participants' PCE. The effect of green performance appeals on WOM was mediated by participants' anticipatory hope when their PCE was low; however, when participants' PCE was high, the mediation was not significant. The findings show that advertising appeals highlighting the effectiveness of green performance can attract consumers who do not believe that product consumption affects a sustainable environment and spread WOM. This research provides insights to fashion brands by suggesting effective green advertising strategies that can increase consumers' voluntary information-sharing behavior.

Recent progress in using Drosophila as a platform for human genetic disease research

  • Wan Hee Yoon
    • Journal of Genetic Medicine
    • /
    • v.20 no.2
    • /
    • pp.39-45
    • /
    • 2023
  • As advanced sequencing technologies continue to uncover an increasing number of variants in genes associated with human genetic diseases, there is a growing demand for systematic approaches to assess the impact of these variants on human development, health, and disease. While in silico analyses have provided valuable insights, it is essential to complement these findings with model organism studies to determine the functional consequences of genetic variants in vivo. Drosophila melanogaster is an excellent genetic model for such functional studies due to its efficient genetic technologies, high gene conservation with humans, accessibility to mutant fly resources, short life cycles, and cost-effectiveness. The traditional GAL4-UAS system, allowing precise control of gene expression through binary regulation, is frequently employed to assess the effects of monoallelic variants. Recombinase medicated cassette exchange or CRISPR-Cas9-mediated GAL4 insertion within coding introns or substitution of gene body with Kozak-Gal4 result in the loss-of-function of the target gene. This GAL4 insertion strategy also enables the expression of reference complementary DNA (cDNA) or cDNA carrying genetic variants under the control of endogenous regulatory cis elements. Furthermore, the CRISPR-Cas9-directed tissue-specific knockout and cDNA rescue system provides the flexibility to investigate candidate variants in a tissue-specific and/or developmental-timing dependent manner. In this review, we will delve into the diverse genetic techniques available in Drosophila and their applications in diagnosing and studying numerous undiagnosed diseases over the past decade.

Research on the Impact of Chinese E-commerce Festivals on College Students' Purchase Intentions

  • Shan YI;Liu YUANYUAN;Sun QIUYAN
    • The Journal of Industrial Distribution & Business
    • /
    • v.15 no.9
    • /
    • pp.29-35
    • /
    • 2024
  • Purpose: With the rapid development of the e-commerce industry, online e-commerce festivals represented by the "Double Eleven Online Shopping Festival" and "618 Mid-Year Promotion" in China play a unique role in consumer activities and have an important impact on various consumers. As aborigines in the Internet era, college students have huge consumption potential. In order to meet the pursuit of a better life for college students and achieve impressive business results, e-commerce platforms will launch various e-commerce festivals. Research design, data and methodology: This article constructs a research model based on the stimulus organism response model and clue utilization theory, proposes relevant hypotheses, and uses SPSS 27.0 to test the proposed hypotheses. From the perspectives of promotion level, timeliness, and variety of categories, this study aims to verify the impact of e-commerce festivals on college students' purchasing intentions and draw relevant conclusions. Results: Empirical verification has shown that the promotion level, timeliness, variety of categories, and holiday trust of e-commerce festivals have a significant positive impact on the e-commerce festival trust of college students as a consumer group. Conclusions: The conclusion on college students' purchasing intentions not only has guiding significance for the formulation of marketing strategies for enterprises, but also helps to understand the current behavior patterns of young consumers.

Evaluation of phlorofucofuroeckol-A isolated from Ecklonia cava (Phaeophyta) on anti-lipid peroxidation in vitro and in vivo

  • Lee, Ji-Hyeok;Ko, Ju-Young;Oh, Jae-Young;Kim, Eun-A;Kim, Chul-Young;Jeon, You-Jin
    • ALGAE
    • /
    • v.30 no.4
    • /
    • pp.313-323
    • /
    • 2015
  • Lipid peroxidation means the oxidative degradation of lipids. The process from the cell membrane lipids in an organism is generated by free radicals, and result in cell damage. Phlorotannins, well-known marine brown algal polyphenols, have been utilized in functional food supplements as well as in medicine supplements to serve a variety of purposes. In this study, we assessed the potential anti-lipid peroxidation activity of phlorofucofuroeckol-A (PFF-A), one of the phlorotannins, isolated from Ecklonia cava by centrifugal partition chromatography in 2,2-azobis (2-amidinopropane) dihydrochloride (AAPH)-stimulated Vero cells and zebrafish system. PFF-A showed the strongest scavenging activity against alkyl radicals of all other reactive oxygen species (ROS) and exhibited a strong protective effect against ROS and a significantly strong inhibited of malondialdehyde in AAPH-stimulated Vero cells. The apoptotic bodies and pro-apoptotic proteins Bax and caspase-3, which were induced by AAPH, were strongly inhibited by PFF-A in a dose-dependent manner and expression of Bcl-xL, an anti-apoptotic protein, was induced. In the AAPH-stimulated zebrafish model, additionally PFF-A significantly inhibited ROS and cell death, as well as exhibited a strong protective effect against lipid peroxidation. Therefore, these results suggest that PFF-A has excellent protective effects against ROS and lipid peroxidation induced by AAPH in both an in vitro Vero cell model and an in vivo zebrafish model.

Reflection on Kinetic Models to the Chlorine Disinfection for Drinking Water Production

  • Lee, Yoon-Jin;Nam, Sang-ho
    • Journal of Microbiology
    • /
    • v.40 no.2
    • /
    • pp.119-124
    • /
    • 2002
  • Experiments for the characterization of inactivation were performed in a series of batch processes with the total coliform used as a general indicator organism based on the chlorine residuals as a disinfectant. The water samples were taken from the outlet of a settling basin in a conventional surface water treat- ment system that is provided with the raw water drawn from the mid-stream of the Han River, The inactivation of total coliform was experimentally analysed for the dose of disinfectants contact time, filtration and mixing intensity. The curves obtained from a series of batch processes were shaped with a general tailing-off and biphasic mode of inactivation, i.e. a sharp loss of bacterial viability within 15 min followed by an extended phase. In order to observe the effect of carry-over suspended solids on chlorine consumption and disinfection efficiency, the water samples were filtered, prior to inoculation with coliforms, with membranes of both 2.5$\mu$m and 11.0 $\mu$m pore size, and with a sand tilter of 1.0 mm in effective size and of 1.4 in uniformity coefficient. As far as the disinfection efficiency is concerned, there were no significant differences. The parameters estimated by the models of Chick-Wat-son, Hom and Selleck from our experimental data obtained within 120 min are: log(N/N$\_$0/)=-0.16CT with n=1, leg(N/N$\_$0/)=-0.71C$\^$0.87/ with n 1 for the Chick-Watson model, log (N/N$\_$0/)=-1.87C$\^$0.47/ T$\^$0.36/ for the Hom model, log (MHo)=-2.13log (1+CT/0.11) for the Selleck model. It is notable that among the models reviewed with regard to the experimental data obtained, the Selleck model appeared to most closely resemble the total coliform survival curve.

Evaluation and Assessment of Biosafety for Bacillus thuringiensis (Bt)-transgenic Rice: Responses of Daphnia magna Fed on Bt-transgenic Rice Variety (해충저항성 Bacillus thuringiensis (Bt) 벼의 환경위해성 평가: 해충저항성 Bt벼가 물벼룩(Daphnia magna)에 미치는 영향)

  • Oh, Sung-Dug;Shin, Hye-Chul;Sohn, Soo-In;Lee, Ki-Jong;Kim, Hyo-Jin;Ryu, Tae-Hun;Lee, Jang-Yong;Park, Beom-Seok;Kweon, Soon-Jong;Suh, Seok-Cheol;Park, Jong-Sug
    • Journal of Applied Biological Chemistry
    • /
    • v.54 no.4
    • /
    • pp.296-302
    • /
    • 2011
  • Insect-resistant transgenic rice was developed by inserting the mCry1Ac1 a modified gene from the soil bacterium Bacillus thuringiensis (Bt). For biosafety assessment, we studied the effects on survival of cantor Daphnia magna, a commonly used as a model organism in ecotoxicological studies. D. magna fed on Bt rice and its near non-genetically modified (GM) counterparts (Nakdong) grown in the same environment (100% ground rice suspension). The Bt rice was comfirmed to have the insertion of T-DNA and protein expression by the polymerase chain reaction and ELISA analysis. Feeding study showed similar cumulative immobility and abnormal response of D. magna between Bt rice and non-GM counterparts. 48 h-$EC_{50}$ values of Bt rice and non-GM rice showed 4,429 and 2,889 mg/L respectively. The rice no observed effect concentration (NOEC) values for D. magna was suggested 1,000 mg/L. We conclude that the tested Bt-rice and Nakdong similar cumulative immobility for D. magna the widely used model organism. We found out that there is strong possibility that the growth of Bt rice didn't affect to non-target insects.