• Korean Journal of Optics and Photonics
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• v.3 no.3
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• pp.143-147
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• 1992

1)iscussed in this paper are the effects of phase modulation on the line spread functions (LSF) and MTFs of ;I binocular objective system. The binocular objective lens is made in Korea. It has rotationally symmetric aberrations. The LSFs and MTFs are measured experimentally. The phase modulation is carried out by applying phase retardation $\pi$ on the aperture. The area where the phase is not retarded presents a double annular type. The OTF curves of phase modulated aperture are compared with that of unmodulated aperture. The comparison shows that there is the aberration compensation effect in aberration loaded system. Therefore the performance of many optical system can be improved without any loss of light energy by properly modulating the phase on the aperture.

• Korean Chemical Engineering Research
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• v.57 no.2
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• pp.185-197
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• 2019

Deactivation of porous photocatalytic materials was studied using three types of microstructured particles: macroporous titania particles, titania microspheres, and porous silica microspheres containing CNTs and $TiO_2$ nanoparticles. All particles were synthesized by emulsion-assisted self-assembly using micron-sized droplets as micro-reactors. During repeated cycles of the photocatalytic decomposition reaction, the non-dimensionalized initial rate constants (a) were estimated as a function of UV irradiation time (t) from experimental kinetics data, and the results were plotted for a regression according to the exponentially decaying equation, $a=a_0\;{\exp}(-k_dt)$. The retardation constant ($k_d$) was then compared for macroporous titania microparticles with different pore diameters to examine the effect of pore size on photocatalytic deactivation. Nonporous or larger macropores resulted in smaller values of the deactivation constant, indicating that the adsorption of organic materials during the photocatalytic decomposition reaction hinders the generation of active radicals from the titania surface. A similar approach was adopted to evaluate the activation constant of porous silica particles containing CNT and $TiO_2$ nanoparticles to compare the deactivation during recycling of the photocatalyst. As the amount of CNTs increased, the deactivation constant decreased, indicating that the conductive CNTs enhanced the generation of active radicals in the aqueous medium during photocatalytic oxidation.

• Journal of Environmental Health Sciences
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• v.45 no.4
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• pp.310-320
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• 2019

Objectives: The purpose of this study is to identify the causes of the retardation of administrative relief under the Special Act on Remedy for Damages Caused by Humidifier Disinfectant and to suggest the systematic refurbishment of this act for the quick and fair of relief of damages. Methods: This study was conducted through the application of the case study, literature review and systematic interpretation of law methods. Results: The disease subject to administrative relief under the Special Act is defined as health damage causally associated to a substantial degree with exposure to humidifier disinfectant. This definition is a strict requirement in light of the legislative purpose of prompt and fair relief of damages. Furthermore, the damage relief committee established under the Special Act judged causal relationships according to a rigorous standard in terms of medical certainty. This medical evidence-based judgment is a result of the committee's failure to understand the normative meaning and function of a causal relationship as an outcome of inference based on empirical rules and common sense. Conclusions: Humidifier disinfectant health damage should be defined as a health-related injury capable of occurring or deteriorating after exposure to humidifier disinfectant (HD). If the fact that a particular injury occurred or worsened after exposure to HD was found, then the damage can be presumed as being caused by HD. However, this might not be the case when the injury was considered to have occurred or been exacerbated entirely due to other factors.

• Journal of Genetic Medicine
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• v.16 no.1
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• pp.15-18
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• 2019

SHORT syndrome is an extremely rare congenital condition due to a chromosomal mutation of the PIK3R1 gene found at 5q13.1. SHORT is a mnemonic representing six manifestations of the syndrome: (S) short stature, (H) hyperextensibility of joints and/or inguinal hernia, (O) ocular depression, (R) Rieger anomaly, and (T) teething delay. Other key aspects of this syndrome not found in the mnemonic include lipodystrophy, triangular face with dimpled chin (progeroid facies, commonly referred to as facial gestalt), hearing loss, vision loss, insulin resistance, and intrauterine growth restriction (IUGR). 3q duplication syndrome is rare syndrome that occurs due to a gain of function mutation found at 3q25.31-33 that presents with a wide array of manifestations including internal organ defects, genitourinary malformations, hand and foot deformities, and mental disability. We present a case of a 2 year and 3 month old male with SHORT syndrome and concurrent 3q duplication syndrome. The patient presented at birth with many of the common manifestations of SHORT syndrome such as bossing of frontal bone of skull, triangular shaped face, lipodystrophy, micrognathia, sunken eyes, and thin, wrinkled skin (progeroid appearance). Additionally, he presented with findings associated with 3q duplication syndrome such as cleft palate and cryptorchidism. Although there is no specific treatment for these conditions, pediatricians should focus on referring patients to various specialists in order to treat each individual manifestation.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.409-421
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• 2019

Investigation of hydroelastic responses of high-speed vessels in irregular sea state is of major interest in naval applications. A three dimensional nonlinear time-domain hydroelastic method in oblique irregular waves is developed, in which the nonlinear hydrostatic restoring force caused by instantaneous wetted surface and slamming force are considered. In order to solve the two technical problems caused by irregular sea state, the time-domain retardation function and Proportional, Integral and Derivative (PID) autopilot model are applied respectively. Besides, segmented model tests of a high-speed trimaran in oblique waves are performed. An oblique wave testing system for trimarans is designed and assembled. The measured results of main hull and cross-decks are analyzed, and the differences in distribution of load responses between trimarans and monohull ships are discussed. Finally, from the comparisons, it is confirmed that the present concept for dealing with nonlinear hydroelastic responses of ships in oblique irregular waves is reliable and accurate.

• Development and Reproduction
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• v.26 no.2
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• pp.79-90
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• 2022

Krüppel-like factor 10 (KLF10) regulates various cellular functions, such as proliferation, differentiation and apoptosis, as well as the homeostasis of several types of tissue. In the present study, we attempted a loss-of-function analysis of zebrafish Klf11a and Klf11b, which constitute human KLF10 homologs. Embryos injected with klf11b-morpholino (MO) showed developmental retardation and cell death, whereas klf11a-MO-injected embryos showed normal development. In klf11b-MO-injected embryos, a dramatic increase in the amount of zebrafish p53 mRNA might be the cause of the increase in that of bax. The degree of apoptosis decreased in the klf11b-MO and p53-MO co-injected embryos. These findings imply that KLF10 is a negative regulator of p53-dependent transcription, suggesting that the KLF10/p53 complex may play an important role in apoptosis for maintenance of tissue homeostasis during embryonic development.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.435-444
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• 2003

In 1957, Schwarz and Foltz discovered that selenium (Se) was an essential trace mineral and nutritionists then started extensive studies to figure out the metabolic function of this element which has been called as toxic mineral. The discovery that glutathione peroxidase (GSH-Px) contained Se demonstrated a biochemical role for Se as an essential trace element. The major physiological function of Se containing GSH-Px is thought to maintain low levels of $H_2O_2$ and other hydroperoxides in the cell to prevent tissues from peroxidation damages. It is known that the GSH-Px activity is increased when animals were fed high dietary levels of Se. Chemical properties of Se have much in common with sulfur (S) therefore Se would follow the sulfur pathways in its metabolism in animal body. Two sources of Se are available for supplementation of Se in animal feed. Inorganic Se can also exist in selenide (-2), elemental (0), selenite (+4) and selenate (+6) oxidation state with other minerals. When sulfur in S containing amino acids is replaced by Se, organic Se can be made and named "eleno"prior to the name of S containing amino acid, i.e. selenomethionine. Selenium deficiency affects humans as well as animals and dysfunctions such as exudative diathesis, retained placenta, mastitis, liver necrosis, Keshan disease, numerous diseases and cancer. From several centuries ago, Se toxicity was recognized in various animal species and much of the current toxic Se levels has been established largely based upon the controlled toxicity studies used inorganic Se. Toxic effects of Se in animal result in reduced feed intake, growth retardation, ataxia, diarrhea, alopecia and sloughing of hooves. However, several experiments demonstrated that Se deficiencies or toxicities were varied by dietary Se levels and sources. Recent studies demonstrated that the incidence of colorectal and prostate cancer was reduced by approximately 50% when humans consumed 200 ${\mu}g$ of Se daily.

• Journal of Preventive Medicine and Public Health
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• v.26 no.3 s.43
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• pp.412-429
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• 1993

For the purpose of promotion of mental health in the rural elderly, the author surveyed 558 elderlies aged 60 years or more, and assessed the prevalence rates of depression and cognitive impairment by using self-rating depression scale of Zung (SDS) and the Korean version of mini-mental state examination (MMSEK). Also the association between depression or cognitive function and socio-environmental factors were investigated. The major findings were as follows ; 1. The prevalence rates of severe depression and cognitive impairment were 20.9% and 14.9% in all the elderly of both sexes, respectively. 2. The rates of depression and cognitive impairment increased with increasing age in both sex groups. The mean scores of SDS increased and the mean scores of MMSEK decreased significantly among them (p<0.01). 3. Those being female, widows or widowers, and those having low levels of physical activity, showed significantly high the mean scores of depression and had significantly low the mean scores of cognitive impairment (p<0.01). 4. The depression scores relating to decreased libido, confusion, psychomotor retardation, hopelessness and indecisiveness were relatively high in both sexes. 5. All the items of mini-mental state examination were significantly correlated with depression. 6. In stepwise multiple regression analysis on depression, MMSEK, level of physical activity, chronic disease, marital status and family income were selected as highly correlated variables, and the $R^2$-value for these variables was 33.7%. 7. In stepwise multiple regression analysis on cognitive function, level of physical activity, age, depression, sex and marital status were selected as highly correlated variables, and the $R^2$-value for these variables was 62.6%. The depression and cognitive impairment of the elderly were positively correlated with nearly all sociodemographic variables.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.4
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• pp.339-349
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• 2014

If the maxillomandibular relationship is unstable or requires treatment for improved function and esthetics, the first treatment objective is to provide stable occlusal contacts. The patient has moderate mental retardation. Due to inadequate vertical overjet, horizontal arch malrelation and excessive tooth loss, full mouth rehabilitation was required. The purpose of treatment planning is to establish physiologic maxillomandibular relation. Using cephalometrics for occlusal analysis is an aid to make a decision. The amount of horizontal bone reduction was calculated with evaluating soft tissue profile. After provisional denture placement, healing of the surgical site and newly adapted arch relationship was evaluated. The patient satisfied with esthetics and showed stable holding contacts. Periodic examination is needed to exclude occlusal disharmony.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.2 s.42
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• pp.47-58
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• 2005

Dynamic response analysis in time dimain is conducted for floating bridges with discrete pontoons subject to spatial variation of ground motions. The Spatial variation of ground motions is considered with the coherency function model which represents wave passage, incoherence and local site effects. The superstructure of the bridge is represented by space frame and elastic catenary cable elements, the abutment us modelde with the spring element of FHWA guideline for considering soil structure interaction and the concept of retardation function is utilized to consider the frequency dependency of the hydrodynamic coefficients which are obtainde by boundary element method. multiple support excitations considering the spatial variation. The noticeable amplification of the response can be shown when the spatial variation of ground motions is incorporated in the anallysis of floating bridges.