• Clinical and Experimental Pediatrics
• /
• v.48 no.7
• /
• pp.711-715
• /
• 2005

Purpose : With the recent improved survival of extremely low birth weight infants(ELBWI), enteral feeding has become a major issue. This study investigates the effects of early enteral feeding in ELBWI on their morbidity, duration of hospitalization, and mortality. Methods : ELBWI admitted to the neonatal intensive care unit at Samsung Medical Center from November 1994 to April 2004 who survived more than 14 days were enrolled. ELBWI were divided into two groups : an early feeding group(EF), in which enteral feeding was started within 3 days after birth; and a late feeding group(LF), in which enteral feeding was started beyond 3 days after birth. 80 ELBWI came under EF, and 131 ELBWI under LF. Results : Birth weight and gestational age did not differ between the two groups. In EF, the time to achieve full enteral feeding and the duration of parenteral nutrition were significantly shorter than in LF. The incidence of bronchopulmonary dysplasia was significantly lower in EF, but the incidences of sepsis, necrotizing enterocolitis, and cholestasis were not different between the two groups. There was no difference in the survival rate between the two groups, but the duration of hospitalization was significantly shorter in EF. Conclusion : Early enteral feeding in ELBWI did not increase the incidence of necrotizing enterocolitis and sepsis, but rather decreased the incidence of bronchopulmonary dysplasia and shortened the duration of hospitalization.

• Journal of Nutrition and Health
• /
• v.44 no.2
• /
• pp.131-139
• /
• 2011

The purpose of this study was to obtain information related to life style characteristics, school achievement and snacking behaviors among underweight and overweight adolescents in Ulsan area. The survey was carried out by self-questionnaires with 464 adolescents (333 underweight and 131 overweight). The results were as follows: Average BMI of the subjects was $19.81{\pm}3.10\;kg/m^2$ which was normal range, but average BMI of underweight and overweight were $16.90{\pm}1.19\;kg/m^2$ and $25.38{\pm}2.16\;kg/m^2$ respectively. The 49.5% of underweight and 94.7% of overweight students have correct perception about their body image. In the sleeping time, 58.9% of underweight and 66.4% of overweight students go to bed after PM 12 o'clock. In the regularity of eating breakfast, 68.5% of underweight and 67.9% of overweight students skipping breakfast at least 5 times per week. 32.6% of the subjects had snack once or more a day. Underweight students had more frequently ate snack than overweight students. The criteria of choosing snack were taste (77.4%), nutrition (9.3%), and price (6.3%). Food as snack they frequently had fruits, milk & milk products, cookies in order. Underweight students had more dodkboki & sundae, candy & chocolate and cake & bread than overweight students, although overweight students had more milk & yogurt than underweight students. The group who had a higher school record, they significantly had more fruits, milk & milk products (p < 0.01) and had not less nutritious foods (p < 0.001). This study may provide basic information on weight status, sleeping and snacking behaviors of adolescents. Therefore they should have nutrition education program to improve their life style and snacking patterns for underweight and overweight adolescents toward healthy weight.

• The Journal of the Petrological Society of Korea
• /
• v.21 no.2
• /
• pp.235-247
• /
• 2012

Peridotite xenoliths hosted by alkali basalts from South Korea occur in Baengnyeong Island, Jeju Island, Boeun, Asan, Pyeongtaek and Ganseong areas. K-Ar whole-rock ages of the basaltic rocks range from 0.1 to 18.9 Ma. The peridotites are dominantly lherzolites and magnesian harzburgites, and the constituent minerals are Fo-rich olivine ($Fo_{88.4-92.0}$), En-rich orthopyroxene, Di-rich clinopyroxene, and Cr-rich spinel (Cr# = 7.8-53.6). Hydrous minerals, such as pargasite and phlogopite, or garnet have not been reported yet. The Korean peridotites are residues after variable degree of partial melting (up to 26%) and melt extraction from fertile MORB mantle. However, some samples (usually refractory harzburgites) exhibit metasomatic enrichment of the highly incompatible elements, such as LREE. Equilibration temperatures estimated using two-pyroxene geothermometry range from ca. 850 to $1050^{\circ}C$. Sr and Nd isotopic compositions in clinopyroxene separates from the Korean peridotites show trends between depleted MORB-like mantle (DMM) and bulk silicate earth (BSE), which can be explained by secondary metasomatic overprinting of a precursor time-integrated depleted mantle. The Korean peridotite clinopyroxenes define mixing trends between DMM and EM2 end members on Sr-Pb and Nd-Pb isotopic correlation diagrams, without any corresponding changes in the basement. This is contrary to what we observe in late Cenozoic intraplate volcanism in East Asia which shows two distinct mantle sources such as a DMM-EM1 array for NE China including Baengnyeong Island and a DMM-EM2 array for Southeast Asia including Jeju Island. This observation suggests the existence of large-scale two distinct mantle domains in the shallow asthenosphere beneath East Asia. The Re-Os model ages on Korean peridotites indicate that they have been isolated from convecting mantle between ca. 1.8 and 1.9 Ga.

• Journal of Korean Home Economics Education Association
• /
• v.17 no.2
• /
• pp.79-93
• /
• 2005

The purpose of this was to present the efficient directions of nutrition education for elementary school children. We examined the problems of eating habits. nutrition knowledge, and perception and expectations on nutrition education of elementary school children in school. This study was carried out using a self-administered questionnaire and subjects were 562 elementary school children in Gyeonggi Province. All data in this research was analyzed through SAS program, and the frequency$(\%)$ and the $mean{\pm}S.D.$ on each question were calculated. Data for each group was analyzed according to sex and the difference among the groups were treated for significance by using chi-square test and Student t-test. About $87.6\%$ of the children have a meal over three times a day, and $76.7\%$ answered that they ate at a certain time regularly everyday. Only $69.6\%$ of subjects said that they ate breakfast everyday, showing very high levels of skipping breakfast. The most common frequency of eating snacks was 'once a day' in both sexes(male $52.2\%$, female $48.6\%$). In the perception on the eating habits, $69.3\%$ of children recognized problems on dieting habits, such as unbalanced diet. irregular eating time, and overeating. The perceived and correct knowledge of nutrition were $99.5\%$ and $86.9\%$, respectively. Most of the children$(99.1\%)$ acknowledged that nutrition education need to be carried out in school. And children want to deeply deal with 'cooking', 'growth and nutrition', 'good eating habits', 'nutrition and disease', These results indicated that elementary school children tended to have undesirable eating behaviors, but the rate of children who recognize the importance and the needs of nutrition education in school was high. Therefore, their parents and teachers need to perform continuous education through a curriculum and life instruction so that students have healthy habits by considering what the problems of nutrition habits are, as the elementary students considerably recognize problems of their own dietary habits and needs of nutrition education.

• The korean journal of orthodontics
• /
• v.28 no.2 s.67
• /
• pp.237-253
• /
• 1998

Surgical-orthodontic treatment is performed for the skeletal Class III patients with no remaining growth and too big a skeletal discrepancy (or camouflage treatment, and two jaw surgery is needed in order to have maximum effect in such patients. In two jaw surgery cases, surgical alteration of the occlusal plane is necessary to establish optimal function, esthetics and postoperative sability, therefore the establishment of the occlusal plane is essential in diagnosis and treatment. The object of this study is to evaluate the stability of the indiviual ideal occlusal plane bsaed on the architectural and structural craniofacial analysis of Delaires. Thus, the subjects of this study were 48 patients who underwent two jaw surgery, and divided in two groups. Each group were composed of 24patients, A group were operated with ideal occlusal plane and B group were not. Two groups were compared at the preoperative, immediate postoperative (average 4.3days), and long-term postoperative (average 1.3years) lateral cephalometric radiographs. The following results were obtained: 1. There was no significance in occlusal plane angulation between $T_2\;and\;T_3$. Average long term follow-up changes of occlusal Plane angle were $0.24^{\circ}{\pm}2.43$, with FH plane and $0.15{\circ}{\pm}2.16{\circ}$ with SN plane in all 48 patients. These results demonstrated that the occlusal plane after two jaw surgery in skeletal Class III malocclusion was stable. 2. There was no significance in postoperative stability of occlusal plane between A and B group. 3. There was no significance in postoperative stability of occlusal plane depending on surgeon and operative method within each group. 4. The postoperative changes of occlusal plane were correlated to the postoperative changes of jaw rather than tooth position. 5. There was no correlation between the postoperative changes of occlusal plane and maxillary impaction and mandibular setback with surgery.

• Journal of Aquaculture
• /
• v.11 no.1
• /
• pp.11-17
• /
• 1998

Variations of hepatocyte in the larval liver of grouper, Epinephelus akaara wre examined to understand the effect of starvation during the first feeding period, 3 to 5 days after hatching. Total length of the fed larvae increased from the 5th day after hatching, although no significant difference between the fed and starved larvae was found untill the 4th day after hatching. Survival rate of the starved larvae decreased from the 4th day after hatching, and almost all of the larvae died by the 5th day after hatching. Nuclear size of hepatocyte in the starved larvae starterd to decrease from the 4th day after hatching. The sizes by 4th and 5th days after hatching in the starved larvae were 1.4 to 1.9 times smaller than those in the fed ones. Hepatocytes in the starved larvae showed irregular morphology in which the nuclei were irregularly shrunk and highly compacted from the 4th day, while hepatocyte nuclei in the fed ones maintained their uniform features during the whole experimental period. These results implied that the initial larval food should be supplied at least within the 4th day after hatching. Also, it suggested that the size of hepatocyte nucleus might be and indicator of starvation for wild and cultured grouper larvae.

• Tuberculosis and Respiratory Diseases
• /
• v.47 no.5
• /
• pp.650-659
• /
• 1999

Background/Aims: It is well recognized that all aerobic cells have the protective mechanisms in order to minimize the tissue damage induced by various reactive oxygen species(ROS). Thioredoxin peroxidase(TPX) which has been recently identified and characterized functions to convert peroxide to water. The protein is also found in various subtypes(TPX-A & B, MER5, HS22 and HORF-06) and is known to be ubiquitous in most human cells. Especially, ischemic brain injuries, partial hepatectomy and radiation induced DNA damages. In treating lung cancer, radiation therapy has a major place in the local control and the relief of symptoms, but radiation induced free radical injury and resulting pulmonary fibrosis has been the major drawback of the therapy. However, little is known about the protective mechanisms and biologic modulations against radiation-induced tissue damages. Methods: Eighteen mice were divided into six groups, 3 in each group, and fifteen had received 900cGy of radiation. The mice were sacrificed according to the pre determined time schedule; immediate, 1, 2, 3 and 6 weeks after irradiation. Extracts were made from the lungs of each mice, Western blot analysis of various subtypes of TPX were done after SDS-P AGE. Examination of H & E stained slides from the same irradiated specimens and the control specimens were also performed. Results: No difference in the intensity of the immunoreactive bands in the irradiated lung samples of the mice compared to the unirradiated control was observed regardless of the time intervals, although H & E examination of the sample specimens demonstrated progressive fibrotic changes of the irradiated lung samples. Conclusion: In conclusion, according to our data, it is suggested that various thioredoxin peroxidase subtypes and catalase which are known to be increased in many repair processes may not be involved in the repair of the radiation injury to the lung and subsequent fibrosis.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.20 no.3
• /
• pp.151-157
• /
• 2015

Recent laboratory studies have documented that mixotrophic dinoflagellates Dinophysis spp. and heterotrophic dinoflagellate Oxyphysis oxytoxoides share a common prey, i.e. the mixotrophic ciliate Mesodinium rubrum. Nonetheless, very little is known about the population dynamics and species interactions among these protists in natural environments. To investigate the interactions between the dinoflagellate predators and their ciliate prey in the field, we took the samples twice a day from 26 July to 28 August, 2011 at a fixed station in Masan Bay and analyzed their abundances. During this study, salinity was highly variable, ranging from 5 to 28, due to the periodic input of rainfalls to the sampling station. Water temperature was on average $26.5^{\circ}C$ until 20 August and thereafter was about $21^{\circ}C$ by the end of the sampling period. The ciliate M. rubrum occurred persistently throughout the sampling period, ranging from 13 to $492\;cells\;mL^{-1}$. Cell densities of D. acuminata and O. oxytoxoides ranged from undetectable level to $19,833\;cells\;L^{-1}$ and from undetectable level to $100,333\;cells\;L^{-1}$, respectively. The high abundance of D. acuminata mostly followed the blooming of the ciliate M. rubrum, but it often did not peak even during heavy blooms of the prey, probably due to sensitivity to large salinity fluctuation and also presumably overlapped grazing by other mixotrophic dinoflagellates. The abundance of O. oxytoxoides was detected only when water temperature was lower than $24^{\circ}C$, indicating that water temperature is an important environmental factor to control the population dynamics of the dinoflagellate species.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.20 no.4
• /
• pp.192-198
• /
• 2015

Picophytoplankton, a group of tiny microorganisms of less than $3{\mu}m$, play an important role as a major primary producer in tropical open ocean as well as temperate coastal waters. Until now, more than 20 and 10 clades of Synechococcus and Prochlorococcus, respectively, have been identified in various marine environments, and its biogeographical distribution have been well studied as well as ecological niches of its major clades. To understand a distribution of diverse picocyanobacterial clades and environmental factors regulating their distribution, picocyanobacterial abundance and genetic diversity was investigated in adjacent waters of Dokdo showing diverse physical properties not only by seasonal variation but also by diverse physical processes. Synechococcus abundances were low in winter and then exponentially increased as water temperature increased up to $20^{\circ}C$. Above $20^{\circ}C$, the abundances tended to be saturated. On the contrary, Prochlorococcus was undetected or occupied a minor fraction of picocyanobacteria in most seasons. In summer, however, Prochlorococcus belonging to HLII ecotype occupied a significant fraction (up to 7%) of picocyanobacteria. In spring and early summer, the steep increase of Synechococcus abundances were resulted from growth of cold water-adapted Synechococcus belonging to clades I and IV. In summer, diverse Synechococcus clades including warm and pelagic water-favoring clade II tended to replace clades I and IV with maintaining high abundance. The water-column stability as well as temperature were found to be important factors regulating the Synechococcus abundances. Moreover, inflow and mixing of distinct water masses with different origins exerted significant influence on the composition of Synechococcus in the study area. Thus, physical processes as well as natural seasonal variation of environmental factors should be considered to better understand ecology of planktonic organisms around Dokdo.

• Korean Journal of Ecology and Environment
• /
• v.36 no.3 s.104
• /
• pp.235-241
• /
• 2003

The effect of ultraviolet (UV) radiation on the characteristics of algae-derived dissolved organic matter (DOM) was examined by comparing the biodegradability and DOM fraction distribution of algal DOM before and after UV exposure. Algal DOM from two axenic cultures of Microcystis aeruginosa and Oscillatoria agardhii were irradiated for 24 h at a UV intensity of 42 W/$m^2$. A complete degradation of algal DOM during the UV exposure did not occur, remaining at constant concentrations of dissolved organic carbon(DOC). After UV exposure, however, microbial degradations were reduced by 17% in M. aeruginosa and 53% in O. agardhii, respectively, and decomposition rates also were two times lower in UV exposed algal DOM. In addition, the chemical compositions of algal DOM altered substantially after UV radiation exposure. The proportions of hydrophilic bases (HiB; protein-like DOM) decreased considerably in both algal DOM sources after UV exposure (16.8% and 20.0% of DOM, respectively), whereas those of hydrophilic acids (HiA; carboxylic acids-like DOM) increased as much as the decrease of the HiB fraction. Capillary ion electrophoresis (CE) analysis showed that several carboxylic acids increased significantly after UV exposure, further confirming an increase in HiA fractions. The results of this study clearly indicate that algal DOM can be changed in its chemical composition as well as biodegradability without complete degradation by UV radiation.