• Journal of the Society of Naval Architects of Korea
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• v.47 no.5
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• pp.671-679
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• 2010

This paper introduces a new hull form design method for the bow of a full ship, by actively applying the relation between the fore-body hull form and its wave resistance characteristics. For the hull form design, the Series 60($C_B=0.8$) hull is chosen as the parent ship, and Kracht's charts are used to determine the parameters of the bulbous bow in the early stages of hull form design. Several hull forms have been tested in order to obtain enough hull form variations with various bow shapes and design parameters in the search of the best design. In order to investigate the resistance characteristics of the designed hull forms, numerical simulations with corresponding model tests have been rigorously performed. For the numerical simulations, the Marker-density method is employed to track the nonlinear phenomena of the free surface(program IUBW). Model tests have also been performed to achieve an improved research performance using the designed hulls. Both numerical and experimental results show that the wave resistance of the hull forms can be effectively diminished if the bows are designed using the method introduced in this research. It is also expected that this research can facilitate better productivity in hull form design, especially at the preliminary design stage of a full ship type vessel.

• The Korean Journal of Pain
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• v.34 no.4
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• pp.463-470
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• 2021

Background: Although neuropathic pain is a severe and common pain, its pathophysiology has not been elucidated yet. Studies in recent years have focused on the immune system's role in the pathogenesis of neuropathic pain. The aim of this study was to investigate the role of immunological mechanisms in neuropathic pain and the effect of pregabalin by measuring immunological marker levels in peripheral blood before and after pregabalin treatment in postherpetic neuralgia (PHN) patients with neuropathic pain. Methods: Forty patients diagnosed with PHN were included in the study. CD4, T follicular cells (Tfh: CD4⁺CXCR5⁺PD1⁺), Th17 (CD4⁺CCR6⁺ and CD4⁺IL17A⁺), regulatory T cells (Treg: CD4⁺ CD25⁺foxp3⁺), Th1 (CD4⁺ CXCR3⁺ and CD4⁺ IFN-γ⁺) and Th2 (CD4⁺ IL-4⁺) cell ratios were measured in peripheral blood samples before treatment and after 3 months of treatment. Results: When immunological marker and inflammation parameter levels were compared before and after treatment, the helper T cell ratio (CD3⁺, CD4⁺) was 30.28 ± 12.27% before treatment and 34.93 ± 11.70% after treatment, so there was a statistically significant increase (P = 0.028). Th17 was 4.75 ± 5.02% before treatment and 5.80 ± 3.13% after treatment, and there was a statistically significant increase (P = 0.036). Conclusions: Immunological mechanisms play an essential role in the pathogenesis of neuropathic pain, immunologically based treatment approach will be the critical point of treatment.

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.469-476
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• 2021

Tricholoma matsutake is commercially important wild edible mushroom. The only method for cultivation of T. matsutake has been to use matsutake-infected pine trees. In this study, twenty-one fruiting bodies were collected from the matsutake-infected pine trees in the Hongcheon experimental site in 2020. The fruiting bodies from the existing production area of matsutake-infected pine tree and from its transplantation site were found to be identical through monitoring and analysis of 13 microsatellite markers. Transplanted matsutake-infected pine trees succeeded in fairy-ring formation and matsutake fruiting in 2010 and 2017 to 2020. In conclusion, the matsutake mycelium of transplanted matsutake-infected pine tree originates from the existing matsutake-infected pine tree production.

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.365-373
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• 2010

TILLING (Targeting Induced Local Lesions IN Genomes) is broadly regarded as an excellent methodology for reverse genetics applications. Approximately 15,000 $M_3$ TILLING lines have been developed via the application of gamma-ray irradiation to rice seeds (cv. Donganbyeo), followed by subsequent selections. In an effort to evaluate the genetic diversity of the TILLING population, we have employed the AFLP multiple dominant marker technique. A total of 96 (0.64%) TILLING lines as well as Donganbyeo were selected randomly and their genetic diversity was assessed based on AFLP marker polymorphisms using 5 primer combinations. An average of 100.4 loci in a range of 97 to 106 was detected using these primer combinations, yielding a total of 158 (31.4%) polymorphic loci between Donganbyeo and each of the 96 lines. A broad range of similarity from 80% to 96% with an average of 89.4% between Donganbyeo and each of the 96 lines was also observed, reflecting the genetic diversity of the TILLING population. Approximately 28 polymorphic loci have been cloned and their sequences were BLAST-searched against rice whole genome sequences, resulting in 20 matches to each of the gene bodies including exon, intron, 1 kb upstream and 1 kb downstream regions. Six polymorphic loci evidenced changes in the coding regions of genes as compared to the rice pseudomolecules, 4 loci of which exhibited missense mutations and 2 loci of which exhibited silent mutations. Therefore, the results of our study show that the TILLING rice population should prove to be a useful genetic material pool for functional genomics as well as mutation breeding applications.

• Clinical and Experimental Pediatrics
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• v.62 no.9
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• pp.353-359
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• 2019

Background: Researchers have shown that eosinophil peroxidase (EPO) is a relatively accurate marker of eosinophilia and eosinophil activity. However, its use as a marker of eosinophilic inflammation in nasal secretions is limited because the diagnostic cutoff values of EPO for use as a one-time test for allergic diseases such as allergic rhinitis have not been established. Purpose: To identify the correlation between nasal eosinophil count and EPO in children and adolescents with rhinitis. Methods: We recruited patients <18 years of age with rhinitis for more than 2 weeks or more than 2 episodes a year whose nasal eosinophil and EPO were measured at a single allergy clinic. The eosinophil percentage was calculated by dividing the eosinophil count by the number of total cells under light microscopy at ${\times}1,000$ magnification. EPO and protein were measured from nasal secretions. We retrospectively analyzed the correlation between nasal eosinophils and protein-corrected EPO (EPO/protein) value. Results: Of the 67 patients enrolled, 41 were male (61.2%); the mean age was $8.2{\pm}4.0years$. The median nasal eosinophil count was 1 and percentage was 1%. The median protein-corrected EPO value was $12.5ng/{\mu}g$ (range, $0-31ng/{\mu}g$). There was a statistically significant correlation between eosinophil count and percentage (P<0.001). However, the eosinophil percentage and EPO did not correlate. The eosinophil count and EPO had a statistically significant correlation (P=0.01). The EPO cutoff value examined for nasal eosinophil counts of 2, 5, 10, and 20 was $17.57ng/{\mu}g$ regardless of the reference count. The largest area under the curve value was obtained when the receiver operating characteristic curve was drawn using the eosinophil count of 2. Conclusion: Nasal eosinophil count was significantly associated with protein-corrected EPO.

• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.298-308
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• 2020

Genetic diversity among Thaumatococcus daniellii populations in the southwestern region of Nigeria were assessed using morphometric and molecular markers to determine the population structure and existing genetic relationship for its improvement, conservation and sustainable utilisation. Populations from five locations in each of the six states were used for the study. Morphometric data were collected on folia characters and analysed for variability. Genome DNA was isolated from the plant leaf and amplified by polymerase chain reaction with inter-simple sequence repeat markers (ISSR) to determine the allelic polymorphism, marker effectiveness and genetic relationship of the population. The results showed significant variations in petiole length and leaf dimensions of the populations within and across the states. These morphometric traits are the major parameters that delimit the populations and they correlated significantly at P≤0.05. Analysis of the electrophoregram showed that the ISSR markers are effective for the diversity study. A total of 136 loci were amplified with an average of 7.16 loci per marker, 63.2% of the loci were polymorphic. The Principal Coordinate Analysis revealed that seven factors accounted for 81.6% of the variation and the dendrogram separated the populations into two major groups at a genetic distance of 10 (about 90% similarity) with sub-groups and clusters. Most populations within the state had a high degree of similarity, nonetheless, strong genetic relationship exists among populations from different states. The close relationship between populations across the states suggests a common progenitor, which are likely separated by ecological or geographical isolation mechanisms.

• Asia Marketing Journal
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• v.17 no.1
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• pp.123-148
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• 2015

Built on regulatory focus theory, this article develops a research model proposing the relationship between management controls (outcome, activity and capability), sales employees' prevention and promotion focus and their behavioral responses (feedback seeking from different sources and relationship investment). The model also suggests that salesperson perceived organizational fit (P-O fit) contributes by influencing the situational self-regulatory mechanism based on regulatory fit theory. To analyze the data, a structural equation model procedure using LISREL 8.5 was employed. To access the potential common method bias, the MV" marker method was applied using a scale theoretically unrelated to at least one scale in the analysis as the MV marker. The results showed that the greater the salesperson's perceived activity control system, the greater the extent of employee prevention focus. The findings also showed that output control and capability control system are positively related to the promotion focus of salespeople. Salespeople's prevention focus relates negatively to the relational investment and positively to organization feedback seeking. The results indicate that salespeople who have promotion focus exhibit the predicted positive influence on their relationship investment. A significant contribution of this research framework is suggesting salesperson regulatory focus as a mediator and its' effects on different types of sales-related behaviors. The author suggests that the motivational orientations of salespeople play key roles in shaping feedback seeking behaviors from different sources; broadly, that employees with a promotion focus will be more sensitive to customers' feedback, and employees with a prevention focus will seek more feedback from the organization. Furthermore, salespeople with a promotion focus will invest more resources to build relationships with customers than salespeople with a prevention focus. This research also explains the moderating role of person-organization fit on the effect of salespeople's regulatory focus and behavioral responses based on regulatory fit theory

• Computers and Concrete
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• v.31 no.5
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• pp.457-468
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• 2023

Buildings, bridges, and dams are examples of civil infrastructure that play an important role in public life. These structures are prone to structural variations over time as a result of external forces that might disrupt the operation of the structures, cause structural integrity issues, and raise safety concerns for the occupants. Therefore, monitoring the state of a structure, also known as structural health monitoring (SHM), is essential. Owing to the emergence of the fourth industrial revolution, next-generation sensors, such as wireless sensors, UAVs, and video cameras, have recently been utilized to improve the quality and efficiency of building forensics. This study presents a method that uses a target-based system to estimate the dynamic displacement and its corresponding dynamic properties of structures using UAV-based video. A laboratory experiment was performed to verify the tracking technique using a shaking table to excite an SDOF specimen and comparing the results between a laser distance sensor, accelerometer, and fixed camera. Then a field test was conducted to validate the proposed framework. One target marker is placed on the specimen, and another marker is attached to the ground, which serves as a stationary reference to account for the undesired UAV movement. The results from the UAV and stationary camera displayed a root mean square (RMS) error of 2.02% for the displacement, and after post-processing the displacement data using an OMA method, the identified natural frequency and damping ratio showed significant accuracy and similarities. The findings illustrate the capabilities and reliabilities of the methodology using UAV to evaluate the dynamic properties of structures.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.2
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• pp.160-167
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• 2023

This study focuses on the development of a Last-Mile delivery service using unmanned vehicles to deliver goods directly to the end consumer utilizing drones to perform autonomous delivery missions and an image-based precision landing algorithm for handoff to a robot in an intermediate facility. As the logistics market continues to grow rapidly, parcel volumes increase exponentially each year. However, due to low delivery fees, the workload of delivery personnel is increasing, resulting in a decrease in the quality of delivery services. To address this issue, the research team conducted a study on a Last-Mile delivery service using unmanned vehicles and conducted research on the necessary technologies for drone-based goods transportation in this paper. The flight scenario begins with the drone carrying the goods from a pickup location to the rooftop of a building where the final delivery destination is located. There is a handoff facility on the rooftop of the building, and a marker on the roof must be accurately landed upon. The mission is complete once the goods are delivered and the drone returns to its original location. The research team developed a mission planning algorithm to perform the above scenario automatically and constructed an algorithm to recognize the marker through a camera sensor and achieve a precision landing. The performance of the developed system has been verified through multiple trial operations within ETRI.

• International Journal of Stem Cells
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• v.16 no.4
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• pp.438-447
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• 2023

Recently, ex-vivo gene therapy has emerged as a promising approach to enhance the therapeutic potential of mesenchymal stem cells (MSCs) by introducing functional genes in vitro. Here, we explored the need of using selection markers to increase the gene delivery efficiency and evaluated the potential risks associated with their use in the manufacturing process. We used MSCs/CD that carry the cytosine deaminase gene (CD) as a therapeutic gene and a puromycin resistance gene (PuroR) as a selection marker. We evaluated the correlation between the therapeutic efficacy and the purity of therapeutic MSCs/CD by examining their anti-cancer effect on co-cultured U87/GFP cells. To simulate in vivo horizontal transfer of the PuroR gene in vivo, we generated a puromycin-resistant E. coli (E. coli/PuroR) by introducing the PuroR gene and assessed its responsiveness to various antibiotics. We found that the anti-cancer effect of MSCs/CD was directly proportional to their purity, suggesting the crucial role of the PuroR gene in eliminating impure unmodified MSCs and enhancing the purity of MSCs/CD during the manufacturing process. Additionally, we found that clinically available antibiotics were effective in inhibiting the growth of hypothetical microorganism, E. coli/PuroR. In summary, our study highlights the potential benefits of using the PuroR gene as a selection marker to enhance the purity and efficacy of therapeutic cells in MSC-based gene therapy. Furthermore, our study suggests that the potential risk of horizontal transfer of antibiotics resistance genes in vivo can be effectively managed by clinically available antibiotics.