• Journal of Korean Vacuum Science & Technology
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• v.2 no.2
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• pp.97-100
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• 1998

We have investigated the effects of crystalline activation on solid phase crystallization (SPC) of amorphous silicon (a-Si) thin films. Wet blasting and self ion implantation were employed as the activation treatments to induce macro or micro crystalline damages on deposited a-Si films. Low temperature and larger grain crystallization were obtained by the applied two-step activation. High degree of crystallinity was also observed on both furnace and rapid SPC. crystalline activations showed the promotion of nucleation on the activated regions and the retardation of growth in an amorphous matrix in SPC. The observed behavior of two-step SPC was strongly dependent on the applied activation and annealing processes. It was also found that the diversified effects by macro and micro activations on the SPC were virtually diminished as the annealing temperature increased.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.17 no.2
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• pp.55-62
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• 2017

Gaucher disease (GD) is an autosomal recessive lysosomal storage disorder caused by beta-glucosidase deficiency. An 18 month-old male with hepatosplenomegaly, anemia, thrombocytopenia, and growth retardation referred to our hospital. The patient showed neurological symptoms, such as supranuclear gaze palsy and developmental delay. Bone marrow biopsy performed to rule out malignancy and the results revealed no malignant cell; however, abnormal histiocytes suggesting storage disease was noted. Based on hepatosplenomegaly, bicytopenia and unexplained neurologic manifestations, enzyme activity and genetic analysis were conducted emergently with a strong suspicion of GD. Beta-glucosidase activity in leukocyte was decreased. GBA sequencing to confirm the diagnosis revealed compound heterozygous pathogenic variants (i.e., c.754T>A, c.887G>A), both previously reported as the cause of neuronopathic GD. Under the diagnosis of type 3 GD, the patient immediately received enzyme replacement therapy (ERT). After 17 months of ERT, the size of spleen decreased, and hemoglobin and platelet count returned to normal. In addition, the activity of chitotriosidase and angiotensin converting enzyme decreased. However, myoclonic movement and generalized seizure occurred at the age of 19 months and antiepileptic drug was started. Other neurological deterioration including supranuclear gaze palsy and developmental delay also persisted. A new therapy to overcome neurologic problems should be developed for patients with type 3 GD.

• Journal of Nutrition and Health
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• v.24 no.4
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• pp.366-377
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• 1991

A retrospective cohort study of low- income households was carried out on 679 mother-infant pairs to see the effect of weaning practices on growth between March, 1987 and January, 1988 in one rural area, one small city, and one big city, by measuring weight and height of children and intervewing mothers. The sample children showed a linear growth retardation from around 7 or 8 month based on WAZ and HAZ using the Korea Growth Standard. After adjusting both for birth-weight/length and morbidity effect, the ANCOVA test showed that :1) infants who were given supplements were not greater than those of not given. 2) infants who were eating supplements more frequently did not show a larger WAZ or HAZ than those of not eating or sometimes eating them. 3) The caloric intake rates of those of higher food frequencies were not greater than those of lower food frequencies. The context of nutrition education about weaning practices has to be changed stressing not only the early introduction of supplements but also the adequate amount of food intake to secure the rapid growth at this critical age.

• Clinical and Experimental Pediatrics
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• v.51 no.5
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• pp.546-550
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• 2008

In this untreated classic phenylketonuria (PKU) case, mental retardation is severe; however, there have been individuals- like the mother of this case- who have escaped mental retardation and all the other potential sequelae of phenylketonuria, despite having high blood phenylalanine levels, and very poor dietary control. It appears that they have nearly normal brain phenylalanine levels despite high blood phenylalanine (Phe) levels. A number of studies have now demonstrated considerable variability in blood vs. brain phenylalanine levels in phenylketonuria patients. Outcome of phenylketonuria appears to be related to brain phenylalanine levels. We report a case of "undiagnosed" maternal phenylketonuria syndrome. A female infant had low birth weight (2,400 g) with microcephaly. We examined her family and discovered that her mother was an undiagnosed phenylketonuria patient with a borderline intelligence quotient (IQ). The infant's sister, six years old, was diagnosed with phenylketonuria at the age of four years was mentally retarded and had received an operation for cleft lip and palate. the sister had also had a low birth weight (2,300 g). Her sister and mother were compound heterozygotes (mother: R243Q/Y325X; sister: Y325X/P407S). The infant and father were heterozygous carriers (baby: R243Q/ -; father: P407S/ - ).

• Journal of Music and Human Behavior
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• v.2 no.1
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• pp.17-33
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• 2005

Music has a vital meaning in peoples' lives, mostly as a communication medium for thoughts and feelings. Because music is nonthreatening and nonjudgmental, its viability works for everyone. The purpose of this research is firstly to compare the effectiveness of existing social rehabilitation program and music integrated social rehabilitation program for people with mental retardation. Secondly, the study purported to find out if the music integrated social rehabilitation program was effective, then how various musical activities can assist communication and expression, and further assist social interactions among the people with mental retardation. The data were collected using Emotions Assessment Tool, Social Skills Assessment, and Skills development in Music were used. Also, verbal contents, voices, gestures, nonverbal expressions were observed and analyzed. As the result, it is shown that the music integrated social rehabilitation program has enhanced communicative and expressive skills of adults with mental retardation, and further improved social interactive skills. This implies that music had positive effects to the mental patients on their social relationship activities, than the program without music integration. The results support previous findings that music can be an effective communicative and expression tool.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.202-210
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• 2005

In this study, the fly ash was employed as a possible alternative to the bentonite for its high sorption capacity against cationic heavy metal. To consider the constituents of barrier possibly used, the specimens were mixed with different material contents (fly ash : weathered soil : bentonite), then sorption test was performed. Also the specimens were molded on the wet side of optimum moisture contents like mixing ratio of sorption test and their hydraulic conductivities were measured in flexible-wall permeameters. And to confirm the effect of dissolved cations, the hydraulic conductivity tests were repeated by converting the permeant liquids from water to $Cd^{2+}$ solution. Finally, the Cd-concentration at the effluent was analyzed for 500hrs to compare the effectiveness of each specimen in contaminant retardation. Test results showed that the more the ratio of fly ash increase, the more Kd value increase, and the hydraulic conductivity of weathered soil/bentonite (95:5) mixture was the lowest $(2.9*10^{-8}cm/sec)$, and specimens made of fly ash and fly ash/weathered soil mixtures showed similar hydraulic conductivity. Although the permeant liquid was changed from water to $Cd^{2+}$ solution, the hydraulic conductivity of all specimens except for weathered soil maintained similarly like before. Consequently, the initial breakthrough point of Cd in weathered soil specimen was observed at about 5hrs after the test started while that of fly ash specimens was not observed during the whole test period of 500hrs. The results implied that fly ash had a sufficient retardation capacity against contaminant transport possibly by its high sorption capacity although it showed little effect on the reduction of hydraulic conductivity. Based on the test results, it could be concluded that the fly ash can be possibly used as a suitable barrier material in containment system to attenuate the contaminant transport for its high retardation capacity and for the low cost.

• Applied Chemistry for Engineering
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• v.21 no.6
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• pp.627-631
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• 2010

This study was performed to test the combustion-retardation properties of Pinus rigida-based materials by the treatment of ammonium salts. Pinus rigida plate was soaked by the treatment with three 20 wt% ammonium salt solutions consisting ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP), respectively, at the room temperature. After the drying specimen treated with chemicals, combustion properties were examined by the cone calorimeter (ISO 5660-1). When the ammonium salts were used as the retardant for Pinus rigida, the flame retardancy improved due to the treated ammonium salts in the virgin Pinus rigida. However the specimen shows increasing CO over virgin Pinus rigida and It is supposed that toxicities depend on extents. Also, the specimen with ammonium sulfate showed both the lower total smoke release (TSR) and lower total smoke production (TSP) than those of virgin plate. Among the specimens, the sample treated with diammonium phosphate showed a strong inhibitory effect of combustion.

• Journal of Biosystems Engineering
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• v.15 no.3
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• pp.219-229
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• 1990

The compression creep behavior of grains when loaded depends not only on load but also on duration of load application. The most common methods of studying the load-time characteristics of agricultural products is by employing rheological models such as Burger's model. However it is sometimes not sufficient to describe the viscoelastic behavior of grains to be Burger's model. For this reason, this study was conducted to develop the rheological model which represented the creep compliance response of the rough rice kernel and was a function of initial stress applied and time. The effects of the initial stress applied and the moisture content on the compression creep behavior of the rough rice kernel were analyzed. The results were obtained from the study as follows: 1. Since the viscoelastic behavior of the rough rice kernel was nonlinear, the transient and steady state creep compliance was satisfactorily modelled as follows: $$J({\sigma},t)=A{\sigma}^B[C+Dt-exp(-Ft)]$$ But, for the every stress applied, the compression creep behavior of the samples tested can be well described by Burger's model respectively. 2. The creep compliance, the instantaneous elastic strain, the retarded elastic strain and the viscous strain of the sample tested generally increased in magnitude with increasing the applied initial stress and the moisture content used in the tests. At low moisture content, the creep compliance for the Japonica-type rough rice kernel Was a little higher than those for Indica-type and at high moisture content, vice versa at high moisture content. 3. The retardation times of the samples had not an uniform tendency by the initial stress and the moisture content. The retardation times ranged from 0.66 to 6.76 seconds, and the creep progressed from transient to steady state at a relatively high rate. 4. The less viscous strain than the instantaneous elastic strain for the samples tested indicated that rough rice kernel behaved as a viscoelastic body characterized by elasticity than viscosity.

• Polymer(Korea)
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• v.24 no.4
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• pp.545-555
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• 2000

Surface defects in injection molded parts due to the unsteady flow are related to the dimension of gate, operational conditions and rheological properties of polymer. In this study we have examined surface defects in injection molding for PC, PBT and PC/ABS alloy with several injection speeds. We have used various cavity shapes that are tensile, flexural and impact test specimens with various gate and cavity thicknesses. Through this study we have observed that the formation of surface defect associated with jetting during filling stage in injection molding is strongly related to not on]v die swell but retardation of die swell. Large die swell eliminates jetting however the large retardation of die swell stimulates jetting. Reducing the thickness ratio of cavity to gate can reduce or eliminate jetting and surface defects. It also enlarges process window that can produce steady flow of polymer melt in injection molding.

• Clinical and Experimental Pediatrics
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• v.61 no.7
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• pp.221-225
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• 2018

Purpose: Congenital hypothyroidism (CH) is the most common endocrine disorder in children. Thyroid hormone deprivation results not only in mental retardation but also growth retardation. This study investigates the final height (FH) in Korean patients with CH detected by newborn screening and examines factors that may affect the FH. Methods: The medical records of Korean CH patients (n=45) were reviewed. The FH was examined and target height (TH) was calculated based on mid-parental height. The FH z score (FHZ) and TH z score (THZ) were computed using the 2007 Korean National Growth Chart. The FHZ and THZ were compared with a Student t test. The impact of the etiology of CH (athyreosis, dyshormonogenesis, ectopic thyoid, hypoplastic thyroid), initial serum thyroid stimulating hormone (TSH) level, initial free thyroxine (T4) level, and time of therapy initiation based on FH was assessed. Results: The mean FHZ was $0.10{\pm}1.01$ for male patients and $-0.11{\pm}1.09$ for female patients. There were no significant differences between FHZ and THZ for both female (P=0.356) and male patients (P=0.237). No significant relationship was found between FH and the etiology of CH, initial TSH level, initial free T4 level, and the time of therapy initiation. Conclusion: Early intervention and satisfactory management do not appear to impede growth in Korean patients with CH. Thus, early detection and proper management of patients with CH detected by newborn screening program are necessary.