• Journal of Dairy Science and Biotechnology
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• v.39 no.2
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• pp.63-67
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• 2021

Antibiotics are widely used to improve productivity in the dairy industry. However, the inappropriate use of antibiotics causes the deterioration in the quality of dairy products undergoing fermentation and maturation. Hence, probiotic use is emerging as an alternative to curb the increased utilization of antibiotics. Probiotics are defined as "living microorganisms that, when administered in appropriate amounts, confer health benefits on the host." They may improve host disease resistance by regulating intestinal microflora balance and promote animal growth and development. In the dairy industry, probiotics have been studied to increase milk production by improving digestion in dairy cows, enhance the content of dairy components such as milk fat and protein, reduce the risk of mastitis in cows, and increase calf weight. Thus, the use of probiotics can improve the production and safety of dairy products. However, some probiotics are still unstable during storage and have low quality and safety issues. Therefore, to reduce the use of antibiotics in the dairy industry, probiotics should be developed and produced considering the above-mentioned problems.

• IMMUNE NETWORK
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• v.14 no.1
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• pp.38-44
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• 2014

K/BxN serum can transfer arthritis to normal mice owing to the abundant autoantibodies it contains, which trigger innate inflammatory cascades in joints. Little is known about whether gut-residing microbes affect host susceptibility to autoantibody-mediated arthritis. To address this, we fed C57BL/6 mice with water containing a mixture of antibiotics (ampicillin, vancomycin, neomycin, and metronidazol) for 2 weeks and then injected them with K/BxN serum. Antibiotic treatment significantly reduced the amount of bacterial genomic DNA isolated from fecal samples, in particular a gene encoding 16S ribosomal RNA derived from segmented filamentous bacteria. Arthritic signs, as indicated by the arthritic index and ankle thickness, were significantly attenuated in antibiotic-treated mice compared with untreated controls. Peyer's patches and mesenteric lymph nodes from antibiotic-treated mice contained fewer IL-17-expressing cells than those from untreated mice. Antibiotic treatment reduced serum C3 deposition in vitro via the alternative complement pathway. IL-$17^{-/-}$ congenic C57BL/6 mice were less susceptible to K/BxN serum-transferred arthritis than their wild-type littermates, but were still responsive to treatment with antibiotics. These results suggest that gut-residing microbes, including segmented filamentous bacteria, induce IL-17 production in GALT and complement activation via the alternative complement pathway, which cause the host to be more susceptible to autoantibody-mediated arthritis.

• Journal of Microbiology and Biotechnology
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• v.24 no.6
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• pp.740-747
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• 2014

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is a very serious disease in rice-growing regions of the world. In spite of their economic importance, there are no effective ways of protecting rice plants from this disease. Bacteriophages infecting Xoo affect the population dynamics of the pathogen and consequently the occurrence of the disease. In this study, we investigated the diversity, host range, and infectivity of Xoo phages, and their use as a bicontrol agent on BLB was tested. Among the 34 phages that were isolated from floodwater in paddy fields, 29 belonged to the Myoviridae family, which suggests that the dominant phage in the ecosystem was Myoviridae. The isolated phages were classified into two groups based on plaque size produced on the lawn of Xoo. In general, there was a negative relationship between plaque size and host range, and interestingly the phages having a narrow host range had low efficiency of infectivity. The deduced protein sequence analysis of htf genes indicated that the gene was not a determinant of host specificity. Although the difference in host range and infectivity depending on morphotype needs to be addressed, the results revealed deeper understanding of the interaction between the phages and Xoo strains in floodwater and damp soil environments. The phage mixtures reduced the occurrence of BLB when they were treated with skim milk. The results indicate that the Xoo phages could be used as an alternative control method to increase the control efficacy and reduce the use of agrochemicals.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.1
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• pp.233-241
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• 2013

One fundamental issue in ad hoc networks is the alternative node election problem, which reflects how well a sensor network is monitored or tracked by sensors. In this paper, we proposed EEAP(Energy-Efficient Alternative Paths). This is a method of selecting an alternative node for path routing management. When some node disconnection on the path routing, using pre-selected backup node provides immediately recover the path recovery. When selecting an alternative node of Step-Parents head node on the path management, the node's energy level and distance information are cared in context-awareness. This is not only increased the system's capacity cost effectively, but also reduce transmission power entire nodes consume energy. As a result, each node could efficiently management and improves the life time for mobile host and extends system coverage.

• Journal of Information Processing Systems
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• v.4 no.4
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• pp.133-144
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• 2008

Clusters have become a popular alternative for building high-performance parallel computing systems. Today's high-performance system area network (SAN) protocols such as VIA and IBA significantly reduce user-to-user communication latency by implementing protocol stacks outside of operating system kernel. However, emerging parallel applications require a significant improvement in communication latency. Since the time required for transferring data between host memory and network interface (NI) make up a large portion of overall communication latency, the reduction of data transfer time is crucial for achieving low-latency communication. In this paper, Eager Data Transfer (EDT) mechanism is proposed to reduce the time for data transfers between the host and network interface. The EDT employs cache coherence interface hardware to directly transfer data between the host and NI. An EDT-based network interface was modeled and simulated on the Linux-based, complete system simulation environment, Linux/SimOS. Our simulation results show that the EDT approach significantly reduces the data transfer time compared to DMA-based approaches. The EDTbased NI attains 17% to 38% reduction in user-to-user message time compared to the cache-coherent DMA-based NIs for a range of message sizes (64 bytes${\sim}$4 Kbytes) in a SAN environment.

• The Plant Pathology Journal
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• v.36 no.4
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• pp.305-313
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• 2020

Host shifting and host expansion of fungal plant pathogens increases the rate of emergence of new pathogens and the incidence of disease in various crops, which threaten global food security. Magnaporthe species cause serious disease in rice, namely rice blast disease, as well as in many alternative hosts, including wheat, barley, and millet. A severe outbreak of wheat blast due to Magnaporthe oryzae occurred recently in Bangladesh, after the fungus was introduced from South America, causing great loss of yield. This outbreak of wheat blast is of growing concern, because it might spread to adjacent wheat-producing areas. Therefore, it is important to understand the host range and population structure of M. oryzae and related species for determining the evolutionary relationships among Magnaporthe species and for managing blast disease in the field. Here, we collected isolates of M. oryzae and related species from various Poaceae species, including crops and weeds surrounding rice fields, in Korea and determined their phylogenetic relationships and host species specificity. Internal transcribed spacer-mediated phylogenetic analysis revealed that M. oryzae and related species are classified into four groups primarily including isolates from rice, crabgrass, millet and tall fescue. Based on pathogenicity assays, M. oryzae and related species can infect different Poaceae hosts and move among hosts, suggesting the potential for host shifting and host expansion in nature. These results provide important information on the diversification of M. oryzae and related species with a broad range of Poaceae as hosts in crop fields.

• Journal of Korean Home Economics Education Association
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• v.10 no.1
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• pp.59-76
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• 1998

This study employs a case study method to examine the current implementation of student teaching program in a particular teacher education institution and its affiliated school. The purpose of this study is to improve the quality of home economics student teaching program by promoting collaboration of teacher education institution and host schools. Following five research problems are addressed : (1)Examining the problems of student teaching from the literature review ; (2)Identifying the problems of student teaching recognized by home economics student teachers ; (3)Identifying the problems of student teaching and plans for improvements suggested in the seminar held for home economics teacher ; (4)Analyzing and comparing the differences of opinion between home economics student teaching program ; and (5)Suggesting alternative implementation plans for improving student teaching program by promoting collaboration of teacher education institution and host schools.

• Korean Journal of Poultry Science
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• v.48 no.4
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• pp.297-318
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• 2021

Coccidiosis is a major parasitic disease in the poultry industry, with great economic implications worldwide. It is a ubiquitous protozoan infection caused by several species of the genus Eimeria (host-specific) that colonize and reproduce in the intestine of birds, ultimately altering the health and performance of the flock. At present, several methods are used to diagnose coccidiosis in poultry, including field and laboratory techniques (intestinal lesion scoring, oocyst counting in feces, and biochemical and molecular diagnosis). Traditionally, diagnosed flocks have been treated either by vaccination to improve the active immunity of the birds against coccidiosis or supplementation of prophylactic anticoccidials to ameliorate the deleterious effects of coccidiosis. However, these methods has certain drawbacks such as vaccine-induced coccidiosis, drug resistance, and residual drug accumulation in the host. Consequently, alternative safe anti-coccidial agents, including the use of phytogenic compounds, have been explored for preventing coccidiosis. Here, we provide a simple overview of the literature on poultry coccidiosis by focusing on the etiology, diagnostic practices, and preventive measures.

• Korean Journal of Agricultural Science
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• v.44 no.2
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• pp.145-180
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• 2017

Alternanthera mosaic virus (AltMV) is a member of the genus Potexvirus which has been known for less than twenty years, and has been detected in Australasia, Europe, North and South America, and Asia. The natural host range to date includes species in at least twenty-four taxonomically diverse plant families, with species in at least four other families known to be infected experimentally. AltMV has been shown to differ from Potato virus X (PVX), the type member of the genus Potexvirus, in a number of ways, including the subcellular localization of the Triple Gene Block 3 (TGB3) protein and apparent absence of interactions between TGB3 and TGB2. Differences between AltMV variants have allowed identification of viral determinants of pathogenicity, and identification of residues involved in interactions with host proteins. Infectious clones of AltMV differing significantly in symptom severity and efficiency of RNA silencing suppression have been produced, suitable either for high level protein expression (with efficient RNA silencing suppression) or for Virus-Induced Gene Silencing (VIGS; with weaker RNA silencing suppression), demonstrating a range of utility not available with most other plant viral vectors. The difference in silencing suppression efficiency was shown to be due to a single amino acid residue substitution in TGB1, and to differences in subcellular localization of TGB1 to the nucleus and nucleolus. The current state of knowledge of AltMV biology, including host range, strain differentiation, host interactions, and utility as a plant viral vector for both protein expression and VIGS are summarized.

• Journal of Korean Society of Rural Planning
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• v.19 no.2
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• pp.149-162
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• 2013

This study intended to suggest Voluntourism as a solution for alternative rural tourism for regional activation. Voluntourism is a form of alternative tourism on values of variety of tourism demand from pleasure to virtue. This study analyzed actual state of WWOOF(World-Wide Opportunities on Organic Farms) activities being operated in Korean rural village, one of representative of Voluntourism. Study aimed to explore the possibility of WWOOF activity as one of model of alternative rural tourism. We apply grounded theory method one of qualitative study methods for analysis of WWOOF Activities because WWOOF is still small activity in Korea. In result, we figure out the actual condition of WWOOF Korea activities as a vouluntourism through paradigm model of host and guest who had experience in WWOOF Korea. WWOOF activity is in its early stage so there many tasks. We suggested ideas for improving WWOOF activities to be one of new rural tourism business.