• Macromolecular Research
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• v.17 no.1
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• pp.37-43
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• 2009

To fabricate dental nanocomposites containing finely dispersed silica nanoparticles, nearly monodispersed silica nanoparticles smaller than 25 nm were synthesized without forming any aggregates via a modified sol-gel process. Since silica nanoparticles synthesized by the Stober method formed aggregates when the particle size is smaller than 25 nm, the synthetic method was modified by changing the reaction temperature and adding poly(1-vinyl-2-pyrrolidinone) (PVP) to the reaction mixture. The size of the formed silica nanoparticles was reduced by increasing the reaction temperature or adding PVP. Furthermore, the formation of aggregates with primary silica nanoparticles smaller than 25 nm was prevented by increasing the amount of PVP added to the reaction mixture. To enhance the dispersion of the silica particles in an organic matrix, the synthesized silica nanoparticles were treated with 3-methacryloxypropyltrimethoxysilane ($\gamma$-MPS). A dental nanocomposite containing finely dispersed silica nanoparticles could be produced by using the surface-treated silica nanoparticles.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8455-8461
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• 2015

In this paper, we propose new search algorithms using SVD(Singular Value Decomposition) for fast search of Raman spectrum. In the proposed algorithms, small number of the eigen vectors obtained by SVD are chosen in accordance with their respective significance to achieve computation reduction. By introducing pilot test, we exclude large number of data from search and then, we apply partial distance search(PDS) for further computation reduction. We prepared 14,032 kinds of chemical Raman spectrum as the library for comparisons. Experiments were carried out with 7 methods, that is Full Search, PDS, 1DMPS modified MPS for applying to 1-dimensional space data with PDS(1DMPS+PDS), 1DMPS with PDS by using descending sorted variance of data(1DMPS Sort with Variance+PDS), 250-dimensional components of the SVD with PDS(250SVD+PDS) and proposed algorithms, PSP and PSSP. For exact comparison of computations, we compared the number of multiplications and additions required for each method. According to the experiments, PSSP algorithm shows 64.8% computation reduction when compared with 250SVD+PDS while PSP shows 157% computation reduction.

• Sleep Medicine and Psychophysiology
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• v.8 no.2
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• pp.129-137
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• 2001

Objectives: The purpose of this study is to investigate the effects of 38-hour sleep deprivation on fine motor performance. The Motor Performance Series (MPS) in the Vienna Test System (computerized neurocognitive function tests) was used in this study. Methods: Twenty four subjects participated in this study. Subjects had no past history of psychiatric disorders and physical illness. Subjects had normal sleep-waking cycle without current sleep disturbances and were all right-handed (Annett's Hand Preference Questionnaire: above +9 points). To minimize the learning effects, familiarization with the Vienna Test System was performed one day before the study. Subjects were to get up at 6:00 in the morning after getting enough sleep according to his or her usual sleep-wake cycle. After awakening, subjects remained awake for 38 hours under continuous surveillance. During two consecutive study days, the subjects tested MPS at 7 AM and 7 PM each day, which means the MPS was done four times in total. During the experiment, anything that could affect the subjects' sleep such as coffee, tea, alcohol, a nap, tiring sports, and all medications were prohibited. Results: In MPS, the fine motor functions of both hands decreased after 38 hours of sleep deprivation. The decrement in motor performance was prominent in the dominant right hand. In the right hand, the total number of tapping was reduced (p<.005), and the number of misses (p<.05) and the length of misses (p<.05) of line tracking, the total length of inserting a short pin (p<.01), the total length of inserting a long pin (p<.05), and the number of misses in aiming (p<.05) increased. Such performance decrement was distinct in the morning sessions. Conclusions: These results suggest that fine motor performance decrement during sleep deprivation is predominant in the right hand, which exerts maximal motor function. The finding of decrement in motor function in tapping during sleep deprivation also suggested that the time required for exhaustion of muscles is shortened during sleep deprivation. More deterioration of motor performance was shown in the morning, which could be explained as circadian rhythm effects.

• Journal of mucopolysaccharidosis and rare diseases
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• v.3 no.1
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• pp.9-13
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• 2017

Tandem mass spectrometry and other new technologies for the multiplex and quantitative analysis of dried blood spots have emerged as powerful techniques for the early screening and assessment of newborns for lysosomal storage diseases (LSDs). Screening newborns for these diseases is important, since treatment options, including enzyme replacement therapy or hematopoietic transplantation, are available for some LSDs, such as infant-onset Pompe disease, Fabry disease, some types of mucopolysaccharidoses (MPSs), and Krabbe disease. For these diseases, early initiation of treatment, before symptoms worsen, often leads to better clinical outcomes. Several problems, however, are associated with newborn screening for LSDs, including the development of accurate test methods to reduce low false-positive rates and treatment guidelines for late-onset or mild disease variants, the high costs associated with multiplex assays, and ethical issues. In this review, we discuss the history, current status, and ethical problems associated with the newborn screening for LSDs, including MPSs.

• Journal of the Korean Society of Systems Engineering
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• v.14 no.1
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• pp.44-51
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• 2018

The purpose of RAM analysis in weapon systems is to reduce life cycle costs, along with improving combat readiness by meeting RAM target value. We analyzed the sensitivity of the RAM analysis parameters to the use of the operating system by using the Markov Process based model (MPS, Markov Process Simulation) developed for RAM analysis. A Markov process-based RAM analysis model was developed to analyze the sensitivity of parameters (MTBF, MTTR and ALDT) to the utility of the 81mm mortar. The time required for the application to reach the steady state is about 15,000H, which is about 2 years, and the sensitivity of the parameter is highest for ALDT. In order to improve combat readiness, there is a need for continuous improvement in ALDT.

• Journal of mucopolysaccharidosis and rare diseases
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• v.1 no.2
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• pp.49-53
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• 2015

Prader-Willi syndrome (PWS) is a complex multisystem genetic disorder characterized by hypothalamic-pituitary dysfunction. Many features of PWS indicate a deficiency in growth hormone (GH) production, and these findings provide a rationale for GH therapy in PWS. It is possible that rhGH therapy could have beneficial effects in adults with PWS, similar to those in adults with GH deficiency (GHD) of non-syndromic cause. However, there is a paucity of data on the use of GH in adults with PWS. Here, the previous studies about efficacy and safety of rhGH therapy in PWS adults are summarized. Briefly, rhGH therapy in PWS adults may improve body composition, leading to increased lean body mass and decreased fat mass, as well as decreased subcutaneous and visceral adiposity without overall changes in body mass index. There may be at least transient deterioration in glucose homoeostasis in some PWS patients on rhGH therapy, which requires further study. In addition, clinical care guidelines for rhGH therapy in adults with PWS were suggested.

• Journal of mucopolysaccharidosis and rare diseases
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• v.1 no.2
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• pp.40-43
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• 2015

Prader-Willi syndrome (PWS), a complex genetic disorder, arises from suppressed expression of paternally inherited imprinted genes on chromosome 15q11-q13. Characteristics include short stature, intellectual disability, behavioral problems, hypogonadism, obesity, and reduced bone and muscle. The life expectancy of persons with PWS has increased in recent years. Cardiovascular diseases, diabetes, dermatological, and orthopedic problems are common physical complaints in older people with PWS. Behavioral problems are major concerns in adults with PWS into old age. And aging is also associated with significant social and economic changes. Age-related physical morbidity, physical appearance, behavioral and psychiatric problems, functional decline and economic problems can be combined in older PWS. The care for older people with PWS requires a life span approach that recognizes the presence, progression, and consequences of specific morbidity.

• Korean Journal of Veterinary Service
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• v.22 no.1
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• pp.9-13
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• 1999

Mycoplasmal pneumonia of swine(MPS) cause by Mycoplasma hyopneumoniae has been recognized as a serious impediment to swine production due to chronic respiratory disorder which result in the weight loss and decreased feed conversion. The disease causes a great economic losses in pig industry by characterizing with high morbidity, low mortality, growth retardation and low feed efficiency. The present study was conducted to investigate the titers of antibody against M hyopneumoniae from the regional and seasonal groups of the slaughtered pigs by enzyme-linked immunosorbent assay(ELISA). The result have shown that the average seropositive rate of M hyopneumoniae infection was 84.6% . The regional seropositive rate in Korea showed 87.4% in Kyonggj, 83.4n in Kangwon, 89.2% in Chungnam and 77.6% in Chungbuk area, respectively. Also the seasonal seropositive rate was appeared as 78.6% in spring,90.1% in summer, 76.9% in autumn and 83.8% in winter, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.85.1-85.1
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• 2011

The magnetic field at the surface of the Sun is concentrated in magnetic features that often have spatial extents of 100 km or less. The study of the fine scale structure of the Sun's magnetic field has been hampered by the limited spatial resolution of the available observations. This has recently changed thanks to various new high-resolution facilities, among them the SUNRISE observatory, built around the largest solar telescope to leave the ground, and containing two science instruments. SUNRISE successfully had its first long-duration science flight on a stratospheric balloon in June 2009 and a host of scientific results have been obtained from the data. After a brief introduction to the Sunrise mission, an overview of selected results obtained so far will be given. A reflight at higher solar activity is currently being prepared.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.3 no.1
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• pp.7-15
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• 1997

The purpose of this study was to exame the pain relief effects of myofascial pain syndrome patient by Post-Isometric Relaxation. From July, 1996 to January, 1997, PIR was applied to myofascial pain syndrome associated with musculoskelatal lesions and was examed on 17 muscles in 98 patients at Sun General Hospital, Taejon city. The results of this study were as follows ; 1. Immediate pain relief group was 58(59%). 2. Only tenderness relief group was 24(25%). 3. No effect group was 16(16%). These results could be confirmed that the increased tension of the affected muscles with the resulting pain relieved by restoring the full stretch length of the muscle by PIR.