• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2466-2472
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• 2013

Human immunodeficiency virus type-1 (HIV-1) is a causative agent of Acquired immunodeficiency syndrome (AIDS), which has affected a large population of the world. Viral envelope glycoprotein (gp120) is an intrinsic protein for HIV-1 to enter into human host cells. Molecular docking guided molecular dynamics (MD) simulation was performed to explore the interaction mechanism of heterobiaryl derivative with gp120. MD simulation result of inhibitor-gp120 complex demonstrated stability. Our MD simulation results are consistent with most of the previous mutational and modeling studies. Inhibitor has an interaction with the CD4 binding region. Van der Waals interaction between inhibitor and Val255, Thr257, Asn425, Met426 and Trp427 were important. This preliminary MD model could be useful in exploiting heterobiaryl-gp120 interaction in greater detail, and will likely to shed lights for further utilization in the development of more potent inhibitors.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.251-268
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• 1986

Selecting a site for the safe disposal of radioactive waste requires the evaluation of a wide range of geologic, mineralogic, hydrologic, and physicochemical properties. Although highly diverse, these properties are in fact interrelated. Site requirements are also diverse because they are influenced by the nature of the radionuclides in the waste, for example, their half-lives, specific energy, and chemistry. A fundamental consideration in site selection is the mineralogy of the host rock, and one of the most ubiquitous mineral groups is clay minerals. Clays and clay minerals as in situ lithologic components and engineered barriers may playa significant role in retarding the migration of radionuclides. Their high sorptivity, longevity (stability), low permeability, and other physical factors should make them a very effective retainer of most radionuclides in nuclear wastes. There are, however, some unanswered questions. For example, how will their longevity and physicochemical properties be influenced by such factors as radionuclide concentration, radiation intensity, elevated temperatures, changes in redox condition, pH, and formation fluids for extended periods of time? Understanding of mechanisms affecting clay mineral-radionuclide interactions under prevailing geochemical conditions is important; however, the utilization of experimental geochemical information related to physicochemical properties of clays and clay-bearing materials with geohydrologic models presents a uniquely challenging problem in that many assessments have to be based on model predictions rather than on experiments. These are high-priority research investigations that need to be addressed before complete reliance for disposal area performance is made on clays and clay minerals.

• Biomolecules & Therapeutics
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• v.29 no.4
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• pp.353-364
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• 2021

The gastrointestinal (GI) tract is a series of hollow organs that is responsible for the digestion and absorption of ingested foods and the excretion of waste. Any changes in the GI tract can lead to GI disorders. GI disorders are highly prevalent in the population and account for substantial morbidity, mortality, and healthcare utilization. GI disorders can be functional, or organic with structural changes. Functional GI disorders include functional dyspepsia and irritable bowel syndrome. Organic GI disorders include inflammation of the GI tract due to chronic infection, drugs, trauma, and other causes. Recent studies have highlighted a new explanatory mechanism for GI disorders. It has been suggested that autophagy, an intracellular homeostatic mechanism, also plays an important role in the pathogenesis of GI disorders. Autophagy has three primary forms: macroautophagy, microautophagy, and chaperone-mediated autophagy. It may affect intestinal homeostasis, host defense against intestinal pathogens, regulation of the gut microbiota, and innate and adaptive immunity. Drugs targeting autophagy could, therefore, have therapeutic potential for treating GI disorders. In this review, we provide an overview of current understanding regarding the evidence for autophagy in GI diseases and updates on potential treatments, including drugs and complementary and alternative medicines.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.7
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• pp.48-56
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• 2011

Recently, new storage device SSD(Solid State Disk) based on NAND flash memory is gradually replacing HDD(Hard Disk Drive) in mobile device and thus a variety of research efforts are going on to find the cost-effective ways of performance improvement. By increasing the NAND flash channels in order to enhance the bandwidth through parallel processing, DRAM buffer which acts as a buffer cache between host(PC) and NAND flash has become the bottleneck point. To resolve this problem, this paper proposes an efficient low-cost scheme to increase SSD performance by improving DRAM buffer bandwidth through scheduling techniques which utilize DRAM multi-banks. When both host and NAND flash multi-channels request access to DRAM buffer concurrently, the proposed technique checks their destination and then schedules appropriately considering properties of DRAMs. It can reduce overheads of bank active time and row latency significantly and thus optimizes DRAM buffer bandwidth utilization. The result reveals that the proposed technique improves the SSD performance by 47.4% in read and 47.7% in write operation respectively compared to conventional methods with negligible changes and increases in the hardware.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.1
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• pp.100-108
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• 2003

By choosing Multicast for transmission of educational contents in the Remote Educational System, we can reduce the server load and increase network bandwidth utilization. We design and implement Multicast Middleware for the Remote Educational System in this paper. There are three characteristics in this Multicast Middleware: 1) Through Centralized Multicast Group Management for passive members, it allows a host to make multicast group, which is composed of receivers, called Group Member and who are chosen by the host, called group Maker. Because, all groups are created by the Group Maker in Centralized Group Management, Group Member's join action will be passive 2) Maintenance and recovery of multicast group information in order to restore from exception and crash; the maintenance and recovery mechanism of Group Maker is distinct from that of Group Member. 3) The mechanism which enables to transmit large size multimedia data through multicasting and remove additional copy operation through shared buffer. Fragmentation/de-fragmentation for large data delivery results in additional copy operation in user level. But by using user level shared buffer, it can be done without user Bevel copy operation. By applying to Remote Educational environment which consists of 30 PCs and Fast Ethernet, we can examine the efficiency of this middleware, which can transmit 18frames/sec movie which resolution 320 $\times$ 120 pixels, 128Kbps encoded sound data and some text data.

• Journal of Life Science
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• v.28 no.10
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• pp.1244-1253
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• 2018

Rumen microbiome consists of a wide variety of microorganisms, such as bacteria, archaea, protozoa, fungi, and viruses, that are in a symbiotic relationship in a strict anaerobic environment in the rumen. These rumen microbiome, a vital maker, play a significant role in feed fermentation within the rumen and produce different volatile fatty acids (VFAs). VFAs are essential for energy metabolism and protein synthesis of the host animal, even though emission of methane gas after feed fermentation is considered a negative indicator of loss of dietary energy of the host animal. To improve rumen microbial efficiency, a variety of approaches, such as feed formulation, the addition of natural feed additives, dietary feed-microbes, etc., have taken to increase ruminant performance. Recently with the application of high-throughput sequencing or next-generation sequencing technologies, especially for metagenomics and metatranscriptomics of rumen microbiomes, our understanding of rumen microbial diversity and function has significantly increased. The metaproteome and metabolome provide deeper insights into the complicated microbial network of the rumen ecosystem and its response to different ruminant diets to improve efficiency in animal production. This review summarized some recent advances of rumen microbiome techniques, especially "meta-omics," viz. metagenomic, metatranscriptomic, metaproteomic, and metabolomic techniques to increase feed fermentation and utilization in ruminants.

• Journal of KIISE:Information Networking
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• v.30 no.4
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• pp.461-473
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• 2003

Multimedia applications are much more sensitive to QoS(Quality of Service) than text based ones due to their data continuity. In order to provide a fast moving MH(Mobil Host) using multimedia application with a consistent QoS,an efficient call admission mechanism is in need. This paper proposes the 2SCA(2-Step Call Admission) scheme based on cal admission scheme using pripority to guarantee the consistent QoS for mobile multimedia applications. A calls of MH are classified new calls, hand-off calls, and QoS upgrading calls. The 2SCA is composed of the basic call admission and advanced call admission; the former determines the call admission based on bandwidth available in each cell and the latter determines the call admission by applying DTT(Delay Tolerance Time), PQeueu(Priority Queue), and UpQueue(Upgrade Queue) algorithm according to the type of each call blocked at the basic call admission stage. In order to evaluate the performance of our mechanism, we measure the metrics such as the dropping probability of new calls, dropping probability of hand-off calls, and bandwidth utilization. The result shows that the performance of our mechanism is superior to that of existing mechanisms such as CSP(Complete Sharing Policy), GCP(Guard Channel Policy) and AGCP(Adaptive Guard Channel Policy).

• Korean journal of applied entomology
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• v.59 no.4
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• pp.281-293
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• 2020

The Korean thistle (Cirsium setidens) is grown in Gangwon province as a food ingredient called gondre. Based on regular monitoring of Korean thistle cultivation, we detected local outbreaks of a stick insect causing severe damage. Here we report the identification of the stick insect and its ecological characteristics. The survey involved 3 farms located in Jeongeon-gun, Gangwon province and lasted from May 28 to October 1 in 2019. According to morphological and DNA analyses the stick insect was identified as Ramulus koreanus Kwon Ha and Lee. a member of the family Phasmatidae. Its outbreak in the Korean thistle farms was observed from June 11 to August 22 with peak density on July 23. Spatial distribution analyses, using Taylors power law and Greens index showed that R. koreanus was uniformally distributed. Food consumption rate of Korean thistle leaves was estimated as 60.98±4.35 ㎠/day/adult. The main food plants were identified as Juglans mandshurica and Aronia melanocarpa. Further study needs to pursue the mechanism of the outbreak and its possible impact on agricultural and forest ecosystems. Additionally, means to relieve crop damage need to be identified.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.6
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• pp.835-841
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• 2018

Objective: The aim of this study was to investigate the reversibility and safety of KISS1 metastasis suppressor (KISS1) gene vaccine in immunocastration. Methods: Six eight-week old ram lambs were randomly divided into vaccinated and control groups. The vaccine (1 mg/ram lamb) was injected at weeks 0, 3, and 6 of the study. Blood samples were collected from the jugular vein before primary immunization and at weeks 2, 4, 6, 10, 14, 22, and 30 after primary immunization. All ram lambs were slaughtered at 38 weeks of age, and samples were collected. Results: The specific anti-KISS1 antibody titers in vaccinated animals were significantly higher and the serum testosterone level was significantly lower than those in the control groups from week 4 to 14 after primary immunization (p<0.05). No significant difference was observed at weeks 22 and 30 after the primary immunization. Similar results were also found for scrotal circumference, testicular weight, length, breadth, and spermatogenesis in seminiferous tubules in week 30 after primary immunization. KS (KISS1-hepatitis B surface antigen S) fusion fragment of KISS1 gene vaccine was not detected in host cell genomic DNA of 9 tissues of the vaccinated ram lambs by polymerase chain reaction. Conclusion: The effects of KISS1 gene vaccine in immunocastration were reversible and no integration events were recorded.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.9
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• pp.1776-1785
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• 2015

Content Centric Network (CCN) has been introduced as a new paradigm due to a shift of users's perspective of using Internet from host-centric to content-centric. On the other hand, a demand for video streaming has been increasing. Thus, Adaptive streaming has been introduced and researched for achieving higher user's satisfaction. If an architecture of Internet is replaced with CCN architecture, it is necessary to consider adaptive video streaming in CCN according to the demand of users. However, if the same rate decision algorithm used in Internet is deployed in CCN, there are a limitation of utilizing content store (CS) in CCN router and a problem of reflecting dynamic requirements. Therefore, this paper presents a framework adequate to CCN protocol and cache utilization, adapting content naming method of exploiting regular expression to the rate decision algorithm of the existing adaptive streaming. In addition, it also improves the quality of video streaming and verifies the performance through dynamic expression strategies and selection algorithm of the strategies.