• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.548-557
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• 2019

Staphylococcus species have a ubiquitous habitat in a wide range of foods, thus the ability to identify staphylococci at the species level is critical in the food industry. In this study, we performed rapid identification of Staphylococcus species using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS). MALDI-TOF MS was evaluated for the identification of Staphylococcus reference strains (n = 19) and isolates (n = 96) from various foods with consideration for the impact of sample preparation methods and incubation period. Additionally, the spectra of isolated Staphylococcus strains were analyzed using principal component analysis (PCA) and a main spectra profile (MSP)-based dendrogram. MALDI-TOF MS accurately identified Staphylococcus reference strains and isolated strains: the highest performance was by the EX method (83.3~89.5% accuracy) at species level identification (EDT, 70.3~78.9% accuracy; DT, less than 46.3~63.2% accuracy) of 24-h cultured colonies. Identification results at the genus level were 100% accurate at EDT, EX sample preparation and 24-h incubation time. On the other hand, the DT method showed relatively low identification accuracy in all extraction methods and incubation times. The analyzed spectra and MSP-based dendrogram showed that the isolated Staphylococcus strains were characterized at the species level. The performance analysis of MALDI-TOF MS shows the method has the potential ability to discriminate between Staphylococcus species from foods in Korea. This study provides valuable information that MALDI-TOF MS can be applied to monitor microbial populations and pathogenic bacteria in the food industry thereby contributing to food safety.

• Smart Structures and Systems
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• v.31 no.2
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• pp.101-111
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• 2023

Structural health monitoring (SHM) covers a range of damage detection strategies for buildings. In real-time, SHM provides a basis for rapid decision making to optimise the speed and economic efficiency of post-event response. Previous work introduced an SHM method based on identifying structural nonlinear hysteretic parameters and their evolution from structural force-deformation hysteresis loops in real-time. This research extends and generalises this method to investigate the impact of a wide range of flag-shaped or pinching shape nonlinear hysteretic response and its impact on the SHM accuracy. A particular focus is plastic stiffness (K_p), where accurate identification of this parameter enables accurate identification of net and total plastic deformation and plastic energy dissipated, all of which are directly related to damage and infrequently assessed in SHM. A sensitivity study using a realistic seismic case study with known ground truth values investigates the impact of hysteresis loop shape, as well as added noise, on SHM accuracy using a suite of 20 ground motions from the PEER database. Monte Carlo analysis over 22,000 simulations with different hysteresis loops and added noise resulted in absolute percentage identification error (median, (IQR)) in K_p of 1.88% (0.79, 4.94)%. Errors were larger where five events (Earthquakes #1, 6, 9, 14) have very large errors over 100% for resulted K_p as an almost entirely linear response yielded only negligible plastic response, increasing identification error. The sensitivity analysis shows accuracy is reduces to within 3% when plastic drift is induced. This method shows clear potential to provide accurate, real-time metrics of non-linear stiffness and deformation to assist rapid damage assessment and decision making, utilising algorithms significantly simpler than previous non-linear structural model-based parameter identification SHM methods.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.4
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• pp.516-527
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• 2024

Rapid, early, accurate detection and identification of the various pathogenic agents associated with the development of biological weapons is critical in preventing loss of life and limiting the impact of these organisms when used against civilian or military targets. The aim of this study was to produce a system for the simple, rapid, accurate and simultaneous detection and identification of Ricin, Botulinum toxin B and Staphylococcal enterotoxin B as a proof of principle for developing field appropriate reverse transcription loop-mediated isothermal amplification systems for the accurate identification of potential biological threats. These systems were designed to facilitate the identification of potential threats even in remote or resource-limited locations.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.587-593
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• 2003

There has been much interest in the Bluetooth technology since it could enable users to connect to a wide range of computing and telecommunication devices without the need to carry or connect cables. It delivers opportunities for rapid, ad-hoc connections, and in the future, could possibly enable automatic, unconscious, connections between devices. In this paper, we discussed a scatternet formation protocol for Bluetooth-based ad hoc networks and proposed the identification system of an object using Bluetooth Scatternets. Over the past few years, several studies have been made on the identification of an object by several RF(Radio Frequency) systems. But there are still some problems, the interference of signals as an example, for the identification of an object. The critical question is how to identify an object precisely without the interference of signals. This paper is an investigation of the Scatternet formation protocol for Bluetooth-based ad hoc networks and the identification system of an object using Bluetooth Scatternets composed of multiple Piconets.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.448-455
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• 2003

Because cosmetics are applied directly to human skin, contamination of such products by microorganisms should be carefully avoided. Since cosmetics are usually kept at room temperature and contain large amounts of nitrogen and carbon sources, they may easily become contaminated by a variety of microorganisms, such as bacteria, filamentous fungi, and yeasts. The rapid and accurate identification of these microorganisms is essential to prevent further expansion of such contamination and the damage it causes. However, more than 30 days and laboratory skills are usually necessary in order to identify microorganisms in cosmetic materials. These time and labor constraints may allow further damage of the cosmetic products and thereby harm the consumer.(omitted)

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2635-2639
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• 2013

The rapid and accurate identification of biological agents is a critical step in the case of bio-terror and biological warfare attacks. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry has been widely used for the identification of microorganisms. In this study, we describe a method for the rapid and accurate discrimination of Bacillus anthracis spores using MALDI-TOF MS. Our direct in-situ analysis of MALDI-TOF MS does not involve subsequent high-resolution mass analyses and sample preparation steps. This method allowed the detection of species-specific biomarkers from each Bacillus spores. Especially, B. anthracis spores had specific biomarker peaks at 2503, 3089, 3376, 6684, 6698, 6753, and 6840 m/z. Cluster and PCA analyses of the mass spectra of Bacillus spores revealed distinctively separated clusters and within-groups similarity. Therefore, we believe that this method is effective in the real-time identification of biological warfare agents such as B. anthracis as well as other microorganisms in the field.

• Journal of Microbiology
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• v.39 no.3
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• pp.213-218
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• 2001

The treatment of Patients with bacteraemia and septicemia requires accurate and rapid identification of the pathogen so that the physician can be guided regarding the selection of the proper antimicrobial therapy. The usual procedure is to withdraw an aliquot of the positive blood culture sample for gram staining and subculturing on the media for the growth and subsequent identification, and susceptibility determinations. It was noticed that during the process some microbiologists would sniff the effluent gases that are products of metabolism and in some cases guess the identity of the bacterium. That Prompted us to engage in systematic investigation of two gram positive and two gram negative bacteria using an electronic nose that had been proven successful in distinguishing the aroma of coffee beans from different sources. The investigation was successful in illustrating the efficacy of such a device in this clinical setting to distinguish Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis. A representative set of patterns obtained with this apparatus is displayed as well. A representative set of patterns obtained with this apparatus is displayed as well. No effort was made to determine an optimal set of sensors for some specific set of bacterial metabolism gaseous products.

• Journal of Microbiology
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• v.41 no.4
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• pp.312-319
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• 2003

In an attempt to develop a method for rapid and accurate identification of six Vibrio species that are clinically important and most frequently detected in Korea, 16S rDNA restriction fragment length polymorphism (RFLP) of Vibrio type strains, as well as environmental isolates obtained from the Korean coastal area, was analyzed using ten restriction endonucleases. Digestion of the 16S rDNA fragments amplified by polymerase chain reaction (PCR) with the enzymes gave rise to 2~6 restriction patterns for each digestion for 47 Vibrio strains and isolates. An additional 2~3 restriction patterns were observed for five reference species, including Escherichia coli, Aeromonas hydrophila, A. salmonicida, Photobacterium phosphoreum, and Plesiomonas shigelloides. A genetic distance tree based on RFLP of the bacterial species correlated well with that based on 16S rDNA sequences. The very small 16S rDNA sequence difference (0.1%) between V. alginolyticus and V. parahaemolyticus was resolved clearly by RFLP with a genetic distance of more than 2%. RFLP variation within a species was also detected in the cases of V. parahaemolyticus, V. proteolyticus, and V. vulnificus. According to the RFLP analysis, six Vibrio and five reference species were assigned to 12 genotypes. Using three restriction endonucleases to analyze RFLP proved sufficient to identify the six pathogenic Vibrio species.

• The Plant Pathology Journal
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• v.39 no.3
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• pp.303-308
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• 2023

The global climate change and international trade have facilitated the movement of plants across borders, increasing the risk of introducing novel plant viruses in new territories. Ixora coccinea exhibited virus-like foliar symptoms, including mosaic and mild mottle. An Oxford Nanopore Technologies-based compact and portable MinION platform was used to identify the causal viral pathogen. The complete genome sequence of jasmine virus H (JaVH; 3867 nt, JaVH-CNU) was determined and found to share 88.4-90.3% nucleotide identity with that of Jasminum sambac JaVH isolate in China. Phylogenetic analysis based on the complete amino acid sequences of RNA-dependent RNA polymerase and coat protein revealed that JaVH-CNU was grouped separately with other JaVH isolates. This is the first report of a natural JaVH infection of I. coccinea. The application of rapid nanopore sequencing for plant virus identification was demonstrated and is expected to provide accurate and rapid diagnosis for virus surveillance.

• Korean Journal of Plant Taxonomy
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• v.47 no.2
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• pp.124-131
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• 2017

Species identification is a fundamental and routine process in plant systematics, and linguistic-based dichotomous keys are widely used in the identification process. Recently, novel tools for species identification have been developed to improve the accuracy, ease to use, and accessibility related to these tasks for a broad range of users given the advances in information and communications technology. A visual identification key is such an approach, in which couplets consist of images of plants or a part of a plant instead of botanical terminology. We developed a visual identification key for 101 taxa of Orchidaceae in Korea and evaluated its performance. It uses short statements for image couplets to avoid misinterpretations by users. The key at the initial steps (couplets) uses relatively easy characters that can be determined with the naked eye. The final steps of the visual key provide images of species and information about distributions and flowering times to determine the species that best fit the available information. The number of steps required to identify a species varies, ranging from three to ten with an average of 4.5. A performance test with senior college students showed that species were accurately identified using the visual key at a rate significantly higher than when using a linguistic-based dichotomous key and a color manual. The findings presented here suggest that the proposed visual identification key is a useful tool for the teaching of biodiversity at schools, for the monitoring of ecosystems by citizens, and in other areas that require rapid, easy, and accurate identifications of species.