• International Journal of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.262-268
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• 2023

It is necessary to investigate how age or gender affects visual perception and social skills in late adolescence. A study on the relevance of visual perception in late adolescence, a period that requires social adaptation through the development of social functions, is necessary. The purpose of this study is to investigate the relationship between visual perception and social skills in adolescence. Visual perception and social skill were evaluated for 18-24-year-olds, who are in late adolescence, and were analyzed for gender differences and correlations with chronological age. This study found that there was a difference in visual perceptual function according to gender in late adolescence, and it was significantly higher in men. There was no significant difference in social skills according to gender. However, there was a significantly positive correlation between chronological age and visual perception, but there was no correlation with social skills. These findings provide novel information regarding the developmental course of visual perception and social skill in late adolescence.

• Journal of Environmental Health Sciences
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• v.46 no.4
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• pp.368-375
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• 2020

Objectives: Some animal studies have reported that methyl mercury causes developmental toxicities such as placental and fetal weight loss, but the mechanism is still unclear. This study aimed to investigate the developmental toxicities of methyl mercury, focusing on placental endocrine function and fetal growth retardation in rats. Methods: Positively same-time-mated female Sprague-Dawley rats were purchased on gestational day (GD) eight and treated with 0, 5, 10 and 20 ppm of methyl mercury (n=5) dissolved in tap water from GD eight through 19. During treatment, the drinking water (methyl mercury) intake and body weight of each pregnant rat was measured daily. On day 19, caesarean sections were performed and blood samples were collected. Developmental data such as placental and fetal weights, fetus numbers, and placental efficiency (fetal weight/placental weight) were also collected. Placental prolactin-growth hormone (PRL-GH) family, such as placental lactogen (PL) -Iv, II, and prolactin-like protein (PLP) -B, levels in serum were analyzed by ELISA. Also, placental tissues were assigned to histochemistry. Results: The mean cumulative methyl mercury exposure for the 5, 10, and 20 ppm groups were 2.37, 4.63, and 9.66 mg, respectively. The mean daily exposure of the 5, 10, and 20 ppm groups were 0.24, 0.47, and 0.97 mg, respectively. Maternal body weight increased in accordance with GD. There was no significant difference in weight gain among the experimental groups. Histopathologic changes were not observed in placental tissues among the experimental groups. However, mean placental and fetal weights were lower in the 10 and 20 ppm exposed groups compared to the control. Placental efficiency was also lower in the 10 and 20 ppm exposed groups compared to the control. Serum PL-Iv and II levels were lower in the 10 and 20 ppm exposed groups than the control, in accordance with the changing pattern of placental and fetal weights and placental efficiency. Conclusion: The inhibitory effects of methyl mercury on the serum levels of placental PRL-GH family such as PL-Iv and II may be secondary leads to the reduction of placental efficiency and fetal growth retardation in rats.

• Korean Journal of Animal Reproduction
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• v.20 no.2
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• pp.191-196
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• 1996

The objective of this study were to investigate the effects of culture media and additives on the development of bovine in vitro matured(IVM) and in vitro fertilized(IVF) oocytes. In experiment 1, bovine oocytes were cultured in droplets of TC 199 supplemented with 10% fetal bovine serum(FBS) with or without hormones (5$\mu\textrm{g}$/ml FSH, 5$\mu\textrm{g}$/ml LH, 1$\mu\textrm{g}$/ml E2). Cleavage rates of embryos cultured for 40~44hrs after IVF were higher when embryos were cultured in TC 199 supplemented hormones (68.1%, 921/35) than without hormones (52.7%, 77/146), but the percentages of development beyond morulae stage were not difference (20.7%, 19.4%). In experiment 2, the effects of various media such as TC 199, synthetic oviduct fluid(SOF), CR1aa with different energy source (fatal bovine serum, FBS; bovine serum albumin, BSA) on developmental capacity of IVM/IVF bovine embryos were investigated. The developmental rates into morulae and blastocysts were 27.1, 10.7, 6.3 and 0%, respecitvely, in CR1aa plus 3mg/ml BSA, SOF plus 10% FBS, TC 199 plus 10% FBS, SOF plus 3mg/ml BSA. In experiment 3, the comparisons of bovine embryos developed to morulae and blastocysts in different culture media (TC 199, SOF, CR1aa, Menezo's B2) were investigated. The developmental capacity beyond morulae stage were 32.9, 26.6, 11.1 and 7.1%, respectively, in Menezo's B2 plus BSA, CR1aa plus BSA, SOF plus BSA, TC 199 plus FBS medium. The cell numbers of the blastocyst were not different in different cultrue media. In experiment 4, bovine embryos were co-cultured with vobine oviduct epithelial cells(BOEC) in TC 199 plus FBS, SOF plus BSA, CR1aa plus BSA, Menezo's B2 plus BSA. The morula and blastocyst rates were 44.7, 32.9, 26.0 and 23.3%, respectively, in CR1aa TC 199, SOF, and Menezo's B2 medium. The cell numbers of the blastocyst were similar to those of blastocyst developed in different culture media.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.394-400
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• 1998

Cryopreservation of embryos by vitrification is a simple method to preserve bovine embryos for subsequent embryo transfer, but embryonic viability after vitrification has been inconsistent and low compared with conventional slow freezing. The aim of the present study is to examine the effect of serum or serum albumin in a vitrification solution and epidermal growth factor(EGF) or fibroblast growth factor(FGF) on in vitro viability of bovine blastocysts frozen by vitrification. Bovine blastocysts were produced by in vitro maturation, fertilization of follicular oocytes and culture of embryos in a synthetic oviduct fluid medium(SOFM) containing BSA and 19 essential and nonessential amino acids. Blastocysts with excellent or good morphology were selected at 7 or 8 days after culture and utilized for vitrification. In experiment 1, blastocysts were vitrified in a solution containing semi-fetal calf serum(SFCS) or BSA(5 or 10mg/ml) and then their subsequent viabilities were examined by culturing thawed embryos in a SOFM containing BSA and 19 amino acids. Effect of EGF or FGF added to a SOFM containing polyvinyl alcohol(PVA) on the viability of vitrified-thawed blastocysts was investigated in experiment 2. BSA added at 5 or 10mg/ml to a vitrification solution showed significantly higher(p < 0.05) developmental rate to expanded and hatching blastocysts than SFCS, but there was no significant difference in the developmental rate to hatched blastocysts after thawing. Supplementation of a culture medium with EGF and/or FGF significantly increased(p < 0.05) embryo development to expanded blastocysts compared with control but showed no beneficial effect on the development to hatching or hatched blastocysts. Coculture of thawed embryos with granulosa cells in a TCM 199 containing 10% fetal calf serum(FCS) showed the highest developmental rate to expanded, hatching and hatched blastocysts among the groups tested. In conclusion, supplementation of a vitrification solution with BSA at 5mg/ml and culture of thawed blastocysts in a medium containing EGF and/or FGF can improve in vitro viability of bovine blastocysts frozen by vitrification.

• Journal of Korean Academy of Nursing
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• v.29 no.6
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• pp.1445-1454
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• 1999

This study was designed to investigate the effects of a sensory stimulation program on the growth (weight, height, head circumference, and chest circumference), behavioral development, behavioral states, and the heart rate of the infants. A total of 23 infants of 2 weeks old were divided into sensory stimualtion group (11 infants) and control group (12 infants). The infants of sensory stimulation group had received sensory stimulation for 6 weeks. Sensory stimulation program was composed of tactile and kinesthetic stimulation. We assessed growth, behavioral state and heart rate every week and behavioral development every 2 weeks. The results were as follows: 1. Body weight in sensory stimulation group, from two weeks after the sensory stimulation program, was significantly increased more than control group, but there was no significant difference in height, head circumference, and chest circumference between the two groups. 2. Behavioral developmental score of sensory stimulation group was significantly higher than that of control group from two weeks after the sensory stimulation program. Developmental states of sensory stimulation group showed more 'high average developmental state' than the control group from 4 weeks after sensory stimulation program. 3. Behavioral states of sensory stimulation group after the sensory stimulation program, the 'sleeping state' was significantly increased more than control group. The 'awakening state' and the state of fuss or crying were significantly less than those of the control group. 4. The heart rate of the sensory stimulation group after the sensory stimulation was significantly lower than the control group. These results indicate that the sensory stimulation program decreases heart rate and improves the sleeping state to be effective on promoting the growth and development of the infants. In view of these experiments, we suggest sensory stimulation program might be considered as a nursing intervention for growth and development of the infants not only in clinical settings but also at homes and in the communities.

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.277-281
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• 2006

Fourier transform - infrared spectroscopy (FT-IR) provides biochemical profiles containing overlapping signals from a majority of the compounds that are present when whole cell extracts are analyzed. We attempted to determine the ripeness of strawberry fruit flesh by FT-IR. Fruit ripeness was divided into four developmental stages based on fruit skin color: 'yellow-green', 'pink-green', 'pink', and 'red' stages. Principal component analysis of FT-IR data of inside fruit flesh extracts clustered samples of four different developmental stages into three discrete groups: (1) 'yellow-green' group, (2) 'pink-green' group, and (3) 'pink' and 'red' group. The most remarkable difference between four different developmental stages was found in the carbohydrate fingerprint region $(1,000-1,100cm^{-1})$ of the FT-IR spectrum, indicating that differences in carbohydrate compounds represented the ripeness of strawberry fruit. Overall results indicate that FT-IR in combination with PCA enables discrimination of the ripeness of strawberry fruit flesh.

• Applied Microscopy
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• v.43 no.4
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• pp.133-139
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• 2013

This study was carried out to investigate the effects of pycnogenol (PYC) on the cutaneous wound healing of the mice. The wounds were extracted on days 1, 3, 5, and 7 post-injury for histomorphometrical analysis including wound area, infiltrating inflammatory cells, wound contracture including collagen deposition. As the result, the wound area of PYC-treated group was larger than the control group on days 1 to 7. Inflammatory cells in the PYC-treated wounds were decreased at day 1 compared to the control wound tissue. From day 3 to 7, there was no significant difference between the control and the PYC-treated skin wounds. Though the degree of contraction in the PYC-treated group was lower than that of the control group from days 1 to 5, but appeared significantly higher on day 7. Compared to the control group, collagen accumulation in the PYC-treated group was higher than that of the control group from days 5 to 7. From this result, it may support the possibility that PYC would be useful agent for early inflammatory response and matrix remodeling phase of the skin wounds.

• Korean Journal of Child Education & Care
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• v.18 no.1
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• pp.53-76
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• 2018

The purpose of this study was to investigate the effect of child care type on infant's developmental outcomes assessed by K-ASQ, focusing on the child-centric role of nurture policy. For this, this study categorized child care type into types including home nurturing, child care center, and subtypes of each category. The findings of multiple regression analysis using the first-third wave data of Panel Study of Korean Children(PSKC) are as follows. First, the child care center experience had rather positive effect on the development of all abilities in the infants comparing to home nurturing. Second, the time of attending child care center was differently related to the development of motor, communication, and personal-social skill in infanthood. Finally, the accreditation of child care showed a difference only in terms of social development of infants. In conclusion, even if the experience of using child care center has positive impact on infant's developmental level, it is still in need of improving service quality such as reinforcing accreditation system.

• The Korean Journal of Malacology
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• v.22 no.2
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• pp.167-173
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• 2006

The embryos of marine bivalves have been commonly used in bioassays for quality assessments of marine environments. Although several standard protocols for the developmental bioassay of bivalves have been proposed, only a few trials for application of these protocols in environmental assessments or for the development of a new protocol with Korean species have been conducted. As such, there is a strong need to establish standard bioassay protocols with bivalves commonly found in Korean waters. To determine the sensitivity of Mytilus galloprovincialis to establish a standard bioassay, their fertilized eggs were exposed to six metals (Ag, Cd, Cr, Cu, Ni, and Zn). The order of biological impact was Ag > Cu > Ni > Zn > Cr > Cd and their lowest observed effective concentration were 5, 16.4, 25.4, 142, 187 and 1,500${\mu}g/l$, respectively. The proportion of normal larvae appeared to decrease linearly with the logarithm of each toxicant concentration within the tested range. The average values of median effective concentrations $(EC_{50})$ from the triplicate experiments for Ag, Cd, Cr, Cu, Ni, and Zn were 6.8, 1,797, 786, 16.6, 68.1, and 139.2${\mu}g/l$, respectively. There was a more than 100-fold difference in $EC_{50}$ values of Cu and Cd. The value of $EC_{50}$ or median lethal concentration of Cu was within the range observed for other bivalve developmental bioassays. The overall sensitivity of M. galloprovincialis in the present developmental bioassay was also similar to that of other marine organisms commonly used in aquatic bioassays (e.g. sea urchins, oysters). Hence, the bioassay using the embryo of M. galloprovincialis is considered to be a useful tool to monitor and evaluate the quality of marine aquatic environments.

• Journal of Embryo Transfer
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• v.12 no.3
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• pp.277-282
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• 1997

The purpose of this experiment was to determine the effects of thiol compounds, $\beta$-mercaptoethanol($\beta$-ME) and cystearrone with buffalo rat liver cell(BRLC) co-culture on the development and intracellular glutathione(GSH) concentrations of bovine embryos produced by in vitro inaturation(IVM) and in vitro fertilization(IVF). Bovine IVM /IVF embryos developed to 2~8 cell stage were co-cultured with BRLC in GRlaa with or without thiol compounds. The developmental rate beyond morulae stage in CRlaa containing 0, 10,25 and 50$\pi$M $\beta$-ME with BRLG were 63.0, 74.0, 72.3 and 77.1%, respectively. And the developmental rate with 0, 25, 50 and 75$\pi$M cystearnine with BRLC were 69.6, 77.6, 81.0 and 76.8%, respectively. The developmental rate beyond morulae stage of GRlaa containing thiol compound with BRLG group was higher than that of control group. The intracellular GSH concentrations of blastocysts cultured for 5 days in GRlaa containing 0 and 50$\pi$M $\beta$-ME or cysteamine with BRLG were 81.2 and 86.4, 83.2 and 84.2pM, respectively. The intracellular GSH concentrations of blastocysts in GRlaa containing thiol compounds with BRLG was slightly higher than that of control group The cell numbers of blastocysts were not difference in all experimental groups. These results indicate that thiol compounds with BRLG co-culture was increased the percentage of developed into morulae and blastocysts, and intracellular GSII concentrations of blastocysts embryos.