• Toxicological Research
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• v.30 no.3
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• pp.179-184
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• 2014

Xenobiotics causing a variety of toxicity in biological systems could be classified as two types, inorganic and organic chemicals. It is estimated that the organic xenobiotics are responsible for approximately 80~90% of chemical-induced toxicity in human population. In the class for toxicology, we have encountered some difficulties in explaining the mechanisms of toxicity caused especially by organic chemicals. Here, a simple flowchart was introduced for explaining the mechanism of toxicity caused by organic xenobiotics, as the central dogma of molecular biology. This flowchart, referred to as a central dogma, was described based on a view of various aspects as follows: direct-acting chemicals vs. indirect-acting chemicals, cytochrome P450-dependent vs. cytochrome P450-independent biotransformation, reactive intermediates, reactivation, toxicokinetics vs. toxicodynamics, and reversibility vs. irreversibility. Thus, the primary objective of this flowchart is to help better understanding of the organic xenobiotics-induced toxic mechanisms, providing a major pathway for toxicity occurring in biological systems.

• The korean journal of orthodontics
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• v.10 no.1
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• pp.55-64
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• 1980

The purpose of this study was to investigate the interrelationship of the experimental group and control group by analyzing case histories, intraoral radiographs, orthopantomographs, intraoral slide films and dental casts. The data for this study were complied from 654 outpatients of the Department of Orthodontics, Seoul National University Hospital. The following conclusions were obtained. 1. When one or more thins molar teeth were congenitally missing, the incidence of the other congenitally missing teeth was high. 2. The frequency of congenitally missing teeth was comparatively higher in male, maxilla, class II and class III. 3. The congenitally missing srea of the third molar by Angle's classification was not significant. 4. The order of frequency of congenitally missing teeth was the third molar, the second premolar, the lateral incisor, the first premolar, the central incisor, the canine, the first molar, the second molar.

• Journal of The Korean Society of Clinical Toxicology
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• v.13 no.1
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• pp.43-45
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• 2015

Sulfoxaflor is the first insecticide belonging to the sulfoximine class and is efficient against sap-feeding insects that are resistant to other insecticides. Sulfoxaflor acts as a neurotoxin to the central nervous system of insects compared with very low toxicity to mammalian. We report on a case of a 67-year-old male who ingested insecticide and received conservative treatment for mild metabolic acidosis and gastrointestinal symptoms.

• The Pure and Applied Mathematics
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• v.8 no.2
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• pp.79-85
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• 2001

As most Of distributions in applications have a finite support, we introduce the class of finite distributions with the known shape of their central part and the unknown tails. Furthermore, we use the Huber minimax approach to determine the unknown characteristics of this class. We obtain the least informative distributions minimizing Fisher information for location in the classes of the truncated Gaussian and uniform distributions, and these results give the reasonable values of the thresholds of truncation. The properties of the obtained solutions are discussed.

• Korean Journal of Mathematics
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• v.30 no.3
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• pp.539-553
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• 2022

In the present paper, we aim to obtain several approximation properties of Stancu form Szász-Mirakjan-Durrmeyer operators based on Bézier basis functions with shape parameter λ ∈ [-1, 1]. We estimate some auxiliary results such as moments and central moments. Then, we obtain the order of convergence in terms of the Lipschitz-type class functions and Peetre's K-functional. Further, we prove weighted approximation theorem and also Voronovskaya-type asymptotic theorem. Finally, to see the accuracy and effectiveness of discussed operators, we present comparison of the convergence of constructed operators to certain functions with some graphical illustrations under certain parameters.

• Communications for Statistical Applications and Methods
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• v.31 no.2
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• pp.247-262
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• 2024

In this paper, we explore nonlinear sufficient dimension reduction (SDR) methods, with a primary focus on establishing a foundational framework that integrates various nonlinear SDR methods. We illustrate the generalized sliced inverse regression (GSIR) and the generalized sliced average variance estimation (GSAVE) which are fitted by the framework. Further, we delve into nonlinear extensions of inverse moments through the kernel trick, specifically examining the kernel sliced inverse regression (KSIR) and kernel canonical correlation analysis (KCCA), and explore their relationships within the established framework. We also briefly explain the nonlinear SDR for functional data. In addition, we present practical aspects such as algorithmic implementations. This paper concludes with remarks on the dimensionality problem of the target function class.

• Imaging Science in Dentistry
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• v.37 no.4
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• pp.217-220
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• 2007

Purpose: The purpose of this study was to compare the location of the mandibular canal in Class III malocclusion to its location in normal occlusion for adults. Materials and Methods: For this study 32 skeletal Class III patients and 26 normal patients were observed. Four measurements were taken on cross sectional tomography between the first and second molars: the distance from the mandibular canal to the inner surface of both the buccal and lingual cortices, the distance from the mandibular canal to the inferior border of the mandible, and the buccolingual width of the mandible. The buccolingual location of the canals was classified as lingual, central, or buccal. Each measurement was analyzed with an independent t test to compare Class III malocclusion to normal occlusion. Results: Compared to the control group, the prognathic group had a shorter distance from the canal to the inner surface of the lingual cortex and to the base of the mandible. A higher percentage of the canals were located lingually in the prognathic group. Conclusion: This study showed that the mandibular canal was located more lingually and inferiorly in prognathic patients than in patients with normal occlusion. These results could help surgeons to reduce injuries to the inferior alveolar nerve.

• Journal of Engineering Education Research
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• v.20 no.1
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• pp.53-62
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• 2017

This paper explored how university students viewed flipped learning from their own perspectives. Using qualitative research methods, 5 students from a Computer Graphics course at a mid-scale university in Seoul were interviewed for this purpose. Researchers collected data about their learning experiences, emotions, and reflections about flipped learning in general and its components such as online materials, in-class activities, and instructor guidance. Research findings indicated that students were not so much conscious about the unfamiliarity of the class, the increased work load, nor the online lectures. They rather prioritized 'what they could actually learn' from the course, and thus defined flipped learning as a method which enabled students to constantly check and fill in the gaps in their learning through team-based activities and prompt feedback from the professor. A combination of students' positive attitude and active participation in team-based activities, the overall atmosphere of the department which supported interactivity and collaboration, the professor's emphasis on learning-by-doing and student-centered learning appeared to form their notions of flipped learning. The use of technology did not appear to heavily impact students' conceptions of flipped learning. Researchers suggest that pedagogical beliefs of the professor, culture surrounding the learner, and the good match between the course content and instructional strategies are central for designing a successful flipped learning class.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.2
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• pp.19-27
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• 2016

This study typified the rural centers with myeon locations in Hwasun-gun which showed comprehensive and various class types through settlement class structure analysis. It is also for establishing the awareness of strengthening functions and facilities of the centers and the directions of strengthening it. Subjects of the study could be classified into three types including base type (Neungju-myeon), general type (Nam-myeon) and decline type (Dongbok-myeon) through the analysis of settlement class structure. Neungju-myeon location as the base type could function as the myeon location by itself and tended to serve education, health and welfare functions through the strengthening of central living functions. Nam-myeon location as the general type required sports facilities management based on the vicinity and accessibility to the senior's welfare functions. Dongbok-myeon location as the decline type required the accessibility to public health facilities and the security of vicinity to the facilities because of its high population of the aged.

• Earthquakes and Structures
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• v.3 no.5
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• pp.649-673
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• 2012

Recent studies have highlighted the importance of accounting for aging and deterioration of bridges when estimating their seismic vulnerability. Effects of structural degradation of multiple bridge components, variations in bridge geometry, and comparison of different environmental exposure conditions have traditionally been ignored in the development of seismic fragility curves for aging concrete highway bridges. This study focuses on the degradation of multiple bridge components of a geometrically varying bridge class, as opposed to a single bridge sample, to arrive at time-dependent seismic bridge fragility curves. The effects of different exposure conditions are also explored to assess the impact of severity of the environment on bridge seismic vulnerability. The proposed methodology is demonstrated on a representative class of aging multi-span reinforced concrete girder bridges typical of the Central and Southeastern United States. The results reveal the importance of considering multiple deterioration mechanisms, including the significance of degrading elastomeric bearings along with the corroding reinforced concrete columns, in fragility modeling of aging bridge classes. Additionally, assessment of the relative severity of exposure to marine atmospheric, marine sea-splash and deicing salts, and shows 5%, 9% and 44% reduction, respectively, in the median value bridge fragility for the complete damage state relative to the as-built pristine structure.