• Phonetics and Speech Sciences
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• v.9 no.3
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• pp.1-6
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• 2017

This study examined how early bilingual children produce sounds in their two languages articulated with the same manner of articulation but at different places of articulation. English affricates are palato-alveolar and Korean affricates are alveolar. This study analyzed the frequencies of center of gravity (COG), spectral peak (SP), and the second formant (F2) of word-initial affricates in English and Korean produced by twenty-four early Korean-English bilingual children (aged 4 to 7), and compared them with those of monolingual counterparts in the two languages. If early Korean-English bilingual children produce palato-alveolar affricates in English and alveolar affricates in Korean, they may produce Korean affricates with higher COGs, SPs, and F2s than English affricates. The early Korean-English bilingual children at the age of 4 produced English and Korean affricates with similar COGs, SPs, and F2s, and the COGs, SPs, and F2s of their Korean affricates were similar to those of the Korean monolingual counterparts. However, the early bilingual children at the age of 5 to 7 had lower COGs and SPs for English affricates with higher F2s compared to Korean affricates, and the COGs, SPs, and F2s of their English affricates were similar to those of the English monolingual counterparts.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.4
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• pp.450-455
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• 1991

Pleomorphic adenoma is a circumscribed tumor characterized microscopically by its pleomorphic or mixed appearance, and its clearly recognizable tissue intermingled with areas of mucoid, myxoid, or chondroid appearance. Plemorphic adenoma, the most common tumor of the salivary glands, is now generally accepted as epithelial and benign, and therefore an adenoma. Pleomorphic adenoma occurs about 10 times more often in the parotid gland than in the submandibular gland, and is rare in the sublingual gland of the major salivary gland. And it occurs most often in the parotid and lip, but is very rare in the buccal mucosa of the minor salivary gland. The reported age of occurrence for pleomorphic adenoma ranges from 5 to 84 years, with a peak incidence during the third decade. We experienced a case of pleomorphic adenoma which occurring in buccal mucosa of 13-year-old boy. And so both the site of origin and age of occurrence make this case unusual. This lesion was treated with surgical excision. No specific change has seen in 1 year postoperative follow-up.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.70.2-70.2
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• 2011

We present a study of the metallicities, ages, and alpha-elements of globular clusters (GCs) in nearby giant elliptical galaxies (gEs) (M87, M49, M60, NGC 5128, NGC 1399, NGC 1407, and NGC 4636) using data in the literature. We used only the data for the GCs derived from the comparison of absorption line indices with the single stellar population model. The metallicity distributions of GCs in these gEs are bimodal, showing the existence of metal-poor and metal-rich populations. All these gEs harbor young GCs with ages less than 5 Gyr as well as old GCs. The mean age of the metal-rich GCs ([Fe/H]>-0.9) is about 3 Gyr younger than that of the metal-poor GCs. The mean values for the alpha-elements of the GCs are smaller than or similar to that of the Milky Way GCs. All the GCs in these gEs show an age-metallicity relation; the larger the metallicities of the GCs are, the younger the GCs are. Old GCs with ages > 10 Gyr have two distinct sub-populations (metal poor and metal rich), while young GCs show a broad metallicity distribution with a single peak. We discuss these results in relation with the formation of GCs in gEs.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.31.2-31.2
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• 2013

We use grid-based hydrodynamic simulations to study star formation in nuclear rings in barred galaxies. The gaseous medium is assumed to be infinitesimally thin, isothermal, and unmagnetized. To investigate various situations, we vary the total gas content in the bar regions and the bar growth time. We find that star formation rate (SFR) in a nuclear ring is determined by the mass inflow rate to the ring rather than the total gas mass in the ring. The SFR shows a strong primary burst and weak secondary bursts at early time, and declines to small values at late time. The primary burst is caused by the rapid gas infall to the ring due to the bar growth, with its duration and peak depending on the bar growth time. The secondary bursts result from re-infall of the ejected gas by star formation feedback of the primary burst. When the SFR is low, ages of young star clusters exhibit an azimuthal gradient along the ring since star formation takes place mostly near the contact points between the dust lanes and the nuclear ring. When the SFR is large, on the other hand, star formation is widely distributed throughout the whole length of the ring, with no apparent age gradient of star clusters. Regardless of SFR, star clusters have a positive radial age gradient, with younger clusters located closer to the ring, since the ring shrinks in size over time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.557-562
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• 2002

This study was to estimate population growth parameters of the freshwater bivalve, Corbicula (Corbiculina) papyacca (Heude) in Korea. Samples were collected from Jojong stream in Chungpyeong from September 1999 to August 2000. Ages were determined from the ring of shell, The shell length of the samples ranged from 4,2 mm to 28.1 mm, The ring on the surface of shell was formed once a year from January to March, Marginal increment analysis of shell rings indicated that annuli were formed in June. Spawning period was estimated to be May to August with a peak between June and July through fatness analysis, and thus rings were considered to be true annual marks. Von Bertalanffy's growth parameter were estimated from a nonlinear method with the value of logical maximum shell length ($L_{propto}$) was 34,36 mm, K was 0.1531/year, logical age of shell length 0 ($t_{0}$) was -0,5246 year, and logical maximum total weight ($W_{propto}$) was 11.42 g.

• Journal of Chest Surgery
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• v.16 no.3
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• pp.356-361
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• 1983

Pulmonary tuberculosis is still one of unsolved problems in Korea due to increased number of far-advanced and drug-resistant patients, who have poor pulmonary function. We have analyzed 1332 operated Gases during the period of 1958-1981. Annual incidence of the disease decreased from 110 [1960] to 21 [1980]. The ratio between male and female was 7:3 and the age of peak incidence was in the 3rd and 4th decades. Recently, patients below the age of 20 years were slightly decreased, but above 50 years were slightly increased. The patients consisted of far-advanced case in 60% and moderately-advanced in 39% in 1980, as compared with 40% and 59% correspondingly in 1965. Preoperative sputum positively decreased from 91% [1958-1963] to 43.8% [ 1974-1981 ]. Medically treated patients for more than 3 years increased from 16% [1958-1963] to 51% [1974-1981]. From the view of surgical indication, totally destroyed hung increased from 27% [1958-1963] to 4396 [1974-1981 ]. Therefore, pneumonectomy occupied 53.8% of total surgical management recently. Mode of surgical treatment showed that thoracoplasty [33%], resection [57%] in 1958-1963 and thoracoplasty [2%], resection [98%] in 1974-1981. As Semb`s thoracoplasty was the first choice of treatment until 1960, thereafter resection became the choice. Postoperative mortality increased from 1.6-2.096 to 396 recently as well as morbidity. It was mainly due to increased number of poor pulmonary function and postoperative spread of disease. On the basis of our experience, far-advanced and drug-resistant patients increased in number recently, whose pulmonary function was poor. So postoperative mortality and morbidity increased. Proper surgical intervention should be considered before the appearance of resistance for all chemotherapeutic drugs.

• Journal of Bone Metabolism
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• v.25 no.4
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• pp.213-217
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• 2018

Patients with gastrointestinal disease (GI) are at risk for osteopenia or osteoporosis, which can lead to fractures. Although these patients may be at risk from a young age, gastroenterologists often overlook this fact in practice. There are well-known GI diseases associated with osteopenia and osteoporosis, such as the post-gastrectomy state, inflammatory bowel disease (IBD), and celiac disease. As there is an increase in the prevalence of IBD patients, newly diagnosed celiac disease in adulthood, and gastric cancer survivors following gastrectomy, bone disease in these patients becomes an important issue. Here, we have discussed osteoporosis and fractures in GI disease, especially in the postgastrectomy state, IBD, and celiac disease. Although the pathogenesis of bone loss in each disease has not been fully identified, we have confirmed that the prevalence of osteoporosis and fractures in each of these diseases is high. There are scarce studies comparing the prevalence of osteoporosis or osteoporotic fractures in GI disease patients with studies in postmenopausal women, and specific guidelines for their management in each disease have not been established. Intensive surveillance and management are needed to ensure that these patients attain peak bone mass for age and sex to prevent fractures.

• Clinical and Experimental Pediatrics
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• v.65 no.4
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• pp.182-187
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• 2022

We frequently encounter newborn infants with thrombocytosis in the neonatal intensive care unit. However, neonatal thrombocytosis is not yet fully understood. Thrombocytosis is more frequently identified in newborns and young infants, notably more often in those younger than 2 years than in older children or adults. The production of megakaryocytes (megakaryopoiesis) and platelets (thrombopoiesis) is mainly regulated by thrombopoietin (TPO). Increased TPO levels during infection or inflammation can stimulate megakaryopoiesis, resulting in thrombopoiesis. TPO concentrations are higher in newborn infants than in adults. Levels increase after birth, peak on the second day after birth, and start decreasing at 1 month of age. Initial platelet counts at birth increase with gestational age. Thus, preterm infants have lower initial platelet counts at birth than late-preterm or term infants. Postnatal thrombocytosis is more frequently observed in preterm infants than in term infants. A high TPO concentration and low TPO receptor expression on platelets leading to elevated plasma-free TPO, increased sensitivity of megakaryocyte precursor cells to TPO, a decreased red blood cell count, and immaturity of platelet regulation are speculated to induce thrombocytosis in preterm infants. Thrombocytosis in newborn infants is considered a reactive process (secondary thrombocytosis) following infection, acute/chronic inflammation, or anemia. Thrombocytosis in newborn infants is benign, resolves spontaneously, and, unlike in adults, is rarely associated with hemorrhagic and thromboembolic complications.

• Korean Journal of Poultry Science
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• v.44 no.4
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• pp.245-251
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• 2017

A dose-response experiment was conducted to determine the lysine requirement for broiler breeder hens during pre-peak production. Totally, one hundred and twenty-six flock 23-week-old Ross 308 broiler breeder hens with similar body weight were selected ($2,188{\pm}32g$) for a 6-week experiment. Hens were fed with a basal diet of corn-wheat-soybean meal formulated to achieve the Ross 308 breeder nutrient specifications (2016), except for lysine. The 7 graded, daily lysine intake levels used in this experiment were 732, 785, 838, 891, 944, 997, and 1,050 mg, and hens were restricted to 133 g of feed throughout this experiment. Pen based egg production were recorded once a day and all eggs were weighed daily. Age at sexual maturity was determined when the hens attained age at 25% production. Body weight at 23~29 weeks of age was not affected (P>0.05) by lysine levels. By fitting a linear-plateau model, the daily lysine requirements for feed conversion ratio, total produced egg weight, and age at sexual maturity at 23~29 weeks of age were estimated as 865, 907, and 891 mg, respectively. Using a quadratic-plateau model, the daily lysine requirement at 23~29 weeks of age were estimated as 974, 964, and 950 mg for feed conversion ratio, total produced egg weight, and age at sexual maturity, respectively. These results suggested that the daily lysine requirement for modern broiler breeder hens according to the National Research Council (1994) are insufficient for higher total produced egg weight, sexual maturity, and feed efficiency, and 120% of the NRC recommendation level would improve hen productivity when data are fitted under linear- and quadratic-plateau models.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.562-566
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• 2005

This study was conducted to investigate the developmental relationship between fatty acid composition in different lipid fractions and stearoyl-CoA desaturase (SCD) gene expression in steer muscles during growth. Twenty Hanwoo steers were used at 6, 12, 18, 24 and 30 months of age. Fatty acid composition and SCD mRNA level were analyzed. In the total lipid fraction, developmental profiles of C18:1, as the product of SCD enzyme, and SCD mRNA level were significantly increased between 6 months and 12 months of age. During this period, the percentage of C18:1 increased from 31.9% to 49.5% in the total lipid. The increased C18:1 level was maintained until 30 months of age within the range of 44.8- 49.9%. In contrast, the C18:0 composition decreased with age and this decrease was compensated by the increase of the C18:1. However, the sum of C18:0 and C18:1 was changed before and after 12-month old by a 20% increase. Unlike the C18 fatty acids, the C16 fatty acids such as C16:0 and C16:1 did not show a consistent change with age in steers' muscle. On the other hand, C18:2 proportion as a major polyunsaturated fatty acid in muscle was significantly reduced from 21.1% at 6 months of age to 4.4% at 12-months old and then this reduced level was maintained until 30 months within the range of 7.4-11.4%. As in the C18:1 composition during early stages, a 2-fold significant increase was observed in the $\Delta^9$-desaturase index of C18 fatty acid as a measure of SCD activity, but not in that of C16 fatty acid. Also, the steady-state level of SCD mRNA reached a peak at 12 months of age. Thus, the positive relationship between the C18:1 composition and the $\Delta^9$-desaturase (SCD enzyme) index of C18 fatty acid or SCD mRNA level was demonstrated during growth, but the negative relationship between the C18:2 composition and the above three indices was demonstrated at the same time, indicating that the sharp induction of SCD mRNA may be closely related to the dramatic reduction of C18:2, which is known as a suppressor of SCD gene expression during growth.