• Journal of Veterinary Clinics
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• v.40 no.3
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• pp.189-196
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• 2023

This study was conducted to determine genetic diversities of Eimeria spp. detected from wildlife. From January 2020 to December 2021, molecular analysis was conducted for Eimeria spp. detected from wildlife rescued in Jeonbuk province, Korea. Polymerase chain reaction targeting 18 s rRNA gene for Eimeria spp. detected from 8 domestic pigeon (Columba livia domestica), 1 Oriental turtle dove (Streptopelia orientalis), 1 Eurasian eagle owl (Bubo bubo), 1 Azure-winged magpie (Cyanopica cyanus), 1 Moorhen (Gallinula chloropus), and 1 raccoon dog (Nyctereutes procyonoides) was conducted for phylogenetic analysis. Domestic pigeon and Oriental turtle dove were bound to the same cluster. In addition, carnivorous Eurasian eagle owl and poultry were bound to the same cluster. These results suggest that Eimeria spp. can be shared between similar species regardless of species along the food chain, suggesting that wild birds could be carriers of Eimeria spp. in Korea.

• Journal of People, Plants, and Environment
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• v.22 no.6
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• pp.621-628
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• 2019

The purpose of this study was to investigate the reliability and validity of the Korean version of the Connectedness to Nature Scale(K-CNS), which was translated from the Connectedness to Nature Scale(CNS) developed by Mayer and Frantz. For this study, questionnaires were conducted with a sample of 407 Korean citizens from various backgrounds and regions, with the ages ranging from 17 to 60. Exploratory factor analysis, internal consistency test and correlation checks were conducted on this questionnaires data. The results of exploratory factor analysis supported that the K-CNS has 10 items in a single factor. The internal consistency of the K-CNS was .880. The K-CNS was positively correlated to the NEP (New Environmental Paradigm), satisfaction with life, mental health, compassionate love, and negatively correlated to stress response. In addition, differences were found by group and age, but not by the gender. The K-CNS was higher in the natural-friendly group than in the general group. By age, the K-CNS scores was high in 40s and 50s than 10-39 years old.

• Elastomers and Composites
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• v.58 no.3
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• pp.136-141
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• 2023

Polyacrylic rubber (ACM) is well known for its excellent heat resistance and chemical stability. Additionally, its performance can be readily manipulated by modifying its functional groups, rendering it highly attractive to various industries. However, extreme climate changes have necessitated an expansion of the operating temperature range and lifespan of ACM products. This requires the optimization of both the compounding process and functional-group design. Hence, we investigated the relationship between the cross-linking system and mechanical properties of an ACM with a carboxylic cure site. The crosslink density is determined by chemical kinetics according to the structure of additives, such as diamine crosslinkers and guanidine accelerators. This interaction enables the manipulation of the scotch time and mechanical properties of the compound. This fundamental study on the correlation analysis between cross-linking systems, physical properties, and storage stability can provide a foundation for material research aimed at satisfying the increasingly demanding service conditions of rubber products.

• Progress in Superconductivity and Cryogenics
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• v.25 no.4
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• pp.10-13
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• 2023

To confirm the room-temperature superconductivity at ambient pressure as claimed in recent arXiv preprints by Lee et al., we followed the original authors' systematic solid-state synthesis recipe to reproduce Cu-doped Pb-apatite, known as LK-99. Using X-ray diffraction and Raman spectroscopy, we identified inclusion of various impurities alongside the apatite phase in our sample. While the sample exhibited an overall semiconducting behavior in electrical transport, an intriguing resistivity anomaly at 380 K was observed, possibly originating from a structural phase transition of the Cu_2-δS impurity. Based on the transport and magnetization measurements, we conclude that the sample is a non-magnetic semiconductor, with absence of superconductivity.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.27 no.4
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• pp.311-323
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• 2023

This paper introduces the industrial problem, the solution, and the results of the research conducted with Define Inc. The client company wanted to improve the performance of an object detection model on the floor plan dataset. To solve the problem, we analyzed the operational principles, advantages, and disadvantages of the existing object detection model, identified the characteristics of the floor plan dataset, and proposed to use of YOLO v5 as an appropriate object detection model for training the dataset. We compared the performance of the existing model and the proposed model using mAP@60, and verified the object detection results with real test data, and found that the performance increase of mAP@60 was 0.08 higher with a 25% shorter inference time. We also found that the training time of the proposed YOLO v5 was 71% shorter than the existing model because it has a simpler structure. In this paper, we have shown that the object detection model for the floor plan dataset can achieve better performance while reducing the training time. We expect that it will be useful for solving other industrial problems related to object detection in the future. We also believe that this result can be extended to study object recognition in 3D floor plan dataset.

• Journal of The Korean Association For Science Education
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• v.27 no.6
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• pp.529-545
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• 2007

Questioning forms an integral part of most strategies for effective teaching when the class consists of difficult content. Science including chemistry is usually content-rich, but difficult to understand without supporting lab experiments, subsidiary visual materials and model kits. Engaging the attention and interest of students in such a subject, therefore, is the key to the success of a daily lesson in the classroom. However, generating meaningful questions requires a certain level of information and metacognitive skills on the part of the teacher. The purpose of this study was to find out the framework of effective teachers' questioning with a large group in chemistry class: how teachers used questioning to engage their students in such a big class, to identify a variety of forms of feedback provided by students and to develop a model of question-inducing strategies. We investigated the teachers' recognition of their questioning and the students' recognition of teachers' questioning by surveying over 82 teachers and 434 students in Korea. The survey findings show that the questionnaire can be categorized into four elements: the theme of the teachers' questions (T), students' inquiries (I), methods of teachers' questioning (M) and encouragement of students (E). These elements can be analyzed and sub-categorized to find out which elements are effective in good questioning, even though the elements are interwoven tetrahedrally.

• Korean Journal of Materials Research
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• v.34 no.2
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• pp.105-110
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• 2024

Scanning probe microscopy (SPM) has become an indispensable tool in efforts to develop the next generation of nanoelectronic devices, given its achievable nanometer spatial resolution and highly versatile ability to measure a variety of properties. Recently a new scanning probe microscope was developed to overcome the tip degradation problem of the classic SPM. The main advantage of this new method, called Reverse tip sample (RTS) SPM, is that a single tip can be replaced by a chip containing hundreds to thousands of tips. Generally for use in RTS SPM, pyramid-shaped diamond tips are made by molding on a silicon substrate. Combining RTS SPM with Scanning spreading resistance microscopy (SSRM) using the diamond tip offers the potential to perform 3D profiling of semiconductor materials. However, damage frequently occurs to the completed tips because of the complex manufacturing process. In this work, we design, fabricate, and evaluate an RTS tip chip prototype to simplify the complex manufacturing process, prevent tip damage, and shorten manufacturing time.

• Journal of Veterinary Science
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• v.25 no.1
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• pp.10.1-10.11
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• 2024

In livestock industry, there is growing interest in methods to increase the production efficiency of livestock to address food shortages, given the increasing global population. With the advancements in gene engineering technology, it is a valuable tool and has been intensively utilized in research specifically focused on human disease. In historically, this technology has been used with livestock to create human disease models or to produce recombinant proteins from their byproducts. However, in recent years, utilizing gene editing technology, cattle with identified genes related to productivity can be edited, thereby enhancing productivity in response to climate change or specific disease instead of producing recombinant proteins. Furthermore, with the advancement in the efficiency of gene editing, it has become possible to edit multiple genes simultaneously. This cattle breed improvement has been achieved by discovering the genes through the comprehensive analysis of the entire genome of cattle. The cattle industry has been able to address gene bottlenecks that were previously impossible through conventional breeding systems. This review concludes that gene editing is necessary to expand the cattle industry, improving productivity in the future. Additionally, the enhancement of cattle through gene editing is expected to contribute to addressing environmental challenges associated with the cattle industry. Further research and development in gene editing, coupled with genomic analysis technologies, will significantly contribute to solving issues that conventional breeding systems have not been able to address.

• BMB Reports
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• v.57 no.1
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• pp.50-59
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• 2024

The application of gene engineering in livestock is necessary for various reasons, such as increasing productivity and producing disease resistance and biomedicine models. Overall, gene engineering provides benefits to the agricultural and research aspects, and humans. In particular, productivity can be increased by producing livestock with enhanced growth and improved feed conversion efficiency. In addition, the application of the disease resistance models prevents the spread of infectious diseases, which reduces the need for treatment, such as the use of antibiotics; consequently, it promotes the overall health of the herd and reduces unexpected economic losses. The application of biomedicine could be a valuable tool for understanding specific livestock diseases and improving human welfare through the development and testing of new vaccines, research on human physiology, such as human metabolism or immune response, and research and development of xenotransplantation models. Gene engineering technology has been evolving, from random, time-consuming, and laborious methods to specific, time-saving, convenient, and stable methods. This paper reviews the overall trend of genetic engineering technologies development and their application for efficient production of genetically engineered livestock, and provides examples of technologies approved by the United States (US) Food and Drug Administration (FDA) for application in humans.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.3
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• pp.292-301
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• 2024

It is challenging to simultaneously estimate parameters in a stock-recruitment relationship, steepness, and natural mortality rate with the other parameters within an age-structured assessment model even in a data-rich situation. Such a problem leads to uncertainty in estimates of management references such as maximum sustainable yield (MSY), which are affected by those components. The objective of this study was to evaluate the effects of those parameters on MSY by analyzing the process of estimating the MSY. For illustration, we used two data sets: The chub mackerel Scomber japonicus in the Korean waters and the yellowtail flounder Limanda ferruginea in the Southern New England-Mid Atlantic. As a result, the natural mortality rate influenced spawning stock biomass per recruit, yield per recruit, and MSY, while steepness affected MSY. A sensitivity analysis enabled us to estimate the natural mortality rate and steepness. The optimal set of steepness and natural mortality was 1.0 and 0.37 per year for the chub mackerel, and 0.35, and 0.8 per year for the yellowtail flounder, respectively.