• Applied Chemistry for Engineering
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• v.26 no.6
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• pp.698-705
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• 2015

Two series of symmetric dimesogenic compounds containing a butylene or 1-methylbutylene spacer as a flexible group were synthesized. The mesogenic groups of synthesized compounds consist of an azobenzene group with a terminal substituent. Chemical structures as well as, thermal, mesomorphic, and photochemical properties of the synthesized compounds were investigated using FT-IR, $^1H-NMR$, differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and UV-visible spectrometry. P-H, P-F, and $P-OC_6H_{13}$ showed monotropic liquid crystal phases, whereas the others showed enantiotropic liquid crystal phases. Compounds with butylene group as a flexible spacer exhibited wider mesophase temperature ranges and higher thermal transition temperatures than compounds containing a 1-methylbutylene group. Compounds with a high absolute value of the Hammett substituent constant exhibited high thermal transition temperatures and improved stability in the liquid crystal phase. Furthermore, in the absence or presence of UV light illumination, terminal substituents of the azomesogenic group were important factors in deciding the maximum absorbance wavelength (${\lambda}_{max}$) and the rate of photoisomerization (K).

• Journal of Digital Convergence
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• v.11 no.11
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• pp.521-528
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• 2013

This study was performed to examine effects of PNF combined pattern training on balance ability and functional ability of hockey players. In order to achieve this purpose, total 28 participants were separated into two group: 14 comparison group and 14 experiment group, and the experiment group performed PNF combined pattern training for 12 week, 3 times a week, 60 minutes a day. Each group was measured beforehand, after 6 week and 12 week. balance ability was measured using GOOD BALANCE system and functional ability was measured using carioca and shuttle-run test. For statistically verifying above measured values, repeated measure analysis of variance was analyzed and have following results. As the comparing results of balance ability, normal standing eye close(NSEC) was ant-post and velocity moment of experiment group showed significant differences(p<.05). And one leg right eye close(OLREC) was ant-post, med-lat and velocity moment of experiment group showed significant differences (p<.05). Also, dynamic balance ability was ant-post and velocity moment of experiment groups showed significant differences(p<.05). As the comparing results of functional ability, shuttle-run of experiment group sowed significant differences(p<.05). From above results, balance ability of hockey players was shown to be improved through symmetric training of PNF combined pattern applied to hockey players, and it can be considered that this is actively recommended for training method to improve athletic performance of hockey players.

• Neonatal Medicine
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• v.17 no.2
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• pp.224-231
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• 2010

Purpose: Hospital readmissions have recently increased due to early hospital discharge and increased trends in breast-feeding. Neonatal hyperbilirubinemia can lead to fatal permanent neurological sequelae without appropriate management. Early detection and intervention are critical. We evaluated the clinical features, risk factors, and brain MRI findings of Korean newborns with idiopathic nonhemolytic hyperbilirubinemia to determine the optimal management policy. Methods: A retrospective review of the medical records of 79 newborns with idiopathic nonhemolytic hyperbilirubinemia was performed at the NICU of the Kyungpook National University Hospital from January 2006 to September 2009. All patients were 35 or more weeks of gestation, and their peak level of serum total bilirubin was more than 20 mg/dL. Results: The mean gestational age was $38^{+3}{\pm}1^{+4}$ weeks, and the mean age on admission was 8.8$\pm$4.0 days. The mean body weight (3,105$\pm$479 g) was decreased by 2.8$\pm$6.4 percent compared to the mean birth weight (3,174$\pm$406 g). There were no statistically significant differences for the peak serum bilirubin level or the duration and effects of phototherapy between the patients with and without risk factors, which included: breastfeeding, cephalohematoma, subdural hemorrhage, and/or ABO incompatibility. Patients were grouped according to change of body weight. Group I consisted of patients that gained weight compared to birth weight, and group II of patients that lost weight compared to birth weight. There were significant differences in the peak serum total bilirubin level between the two groups. Thirty nine patients had brain MRI evaluation; 21 patients had bilateral symmetric signal intensity increases in the globus pallidus compared to adjacent corticospinal tract and putamen on T1-weighted images. Conclusion: Bilirubin encephalopathy is preventable with early screening and proper management. Parents require instruction on feeding practices and follow-up to prevent complications from idiopathic nonhemolytic hyperbilirubinemia.

• Applied Microscopy
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• v.18 no.1
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• pp.1-20
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• 1988

There's been arguments on the different morphological status between the nucleus accumbens septi and nucleus fundus striati of ventral striatum. Authors carried out the comparative study on the neuronal cell types of these nuclei, in the chick and the rat. Results are summarized as follows: In the nucleus accumbens septi of the chick, there found 3 main cell types. Type I cells are oval or spindle-shaped. They are the most abundant cell types, comprising more than 80% of neurons. The pale nucleus is usually indented. The cytoplasm is also pale and contains small amount of mitochondria, rough r-ER and Golgi complexes. This cell has a few symmetric synapses on the cell membrane. Type II cells are pale large cells. They are polygonal or irregularly-shaped. They contain pale spherical nucleus, and the pale cytoplasm with relatively large amount of mitochondria, free ribosomes and well-developed Golgi complexes. Some axo-somatic synapes are found on the cell. Type III cells are oval or spherical-shaped. The nucleus is relatively pale and large, In the dense cytoplasm, well developed. r-ER formed typical Nissl's body, and there found many mitochondria, ribosomes and lysosomes. In the chick fundus striati nucleus, there also found 3 main cell types. Type I cells are small and spindle-shaped. This type is the most abundant one and constitutes more the 80% of the neurons. Morphological features other than it's shape, is generally similar with that of Type I cell in the nucleus accumbens. Type II cells are irregularly shaped large cells. Dense cytoplasm contains large amount of cell organelles. Some axo-somatic synapses are found. Type III cells are small dense cells. This oval cell contains the oval nucleus, and the plentiful cytoplasm with well developed r-ER, ribosomes and mitochondria. In the nucleus accumbens septi of the rat, there found 4 main cell types. Type I cells are small, oval or spherical cells, comprising more than 90% of all the neurons. Spherical nucleus shows typical chromatin rim along the nuclear membrane. Dense cytoplasm contains many ribosomes and mitochondria. Type II cells are large oval cells. The eccentric nucleus is deeply invaginated. Pale cytoplasm contains large amount of ribosomes, Golgi complexes, mitochondria, and dense bodies. Type III cells are pale, large, oval cells. They contain moderate amount of ribosomes and mitochondria, and some scattered stacks of r-ER. Type IV cells are small pale cells. Small oval nucleus is indented and shows chromatin rim. Only small amount of ribosomes and mitochondria can be found. In the nucleus fundus striati of the rat, there also found 4 main cell types. Type I cells are spherical or oval cells, comprising more than 90% of the neurons. The chromatin rim of the spherical nucleus is not so prominent as compared to the rim of type I cell in the nucleus accumbens septi. The cytoplasm contains moderate amount of mitochondria, ribosomes and some scattered r-ER. A few axo-somatic synapses were found. Type II cells are small round or polygonal cells. Golgi complexes are especially well-developed in this cell type. The cytoplasm also contains moderate amount of mitochondria, ribosomes, and dense bodies. Type III cells are small cells. The large nucleus shows prominent chromatin rim. The cytoplasm contains many ribosomes and mitochondria. Type IV cells are large, spheircal or oval cells. The nucleus is deeply indented. The plentiful cytoplasm contains large amount of ribosomes, mitochondria, Golgi complexes, neurotubules, but not r-ER. In the present study, it is clear that the nucleus accumbens septi and the nucleus fundus striati are independant cell groups, according to their cytoarchitectonics and the ultrastructural features of their cell types.

• KDI Journal of Economic Policy
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• v.12 no.2
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• pp.51-79
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• 1990

Research on technical efficiency, an important dimension of market performance, had received little attention until recently by most industrial organization empiricists, the reason being that traditional microeconomic theory simply assumed away any form of inefficiency in production. Recently, however, an increasing number of research efforts have been conducted to answer questions such as: To what extent do technical ineffciencies exist in the production activities of firms and plants? What are the factors accounting for the level of inefficiency found and those explaining the interindustry difference in technical inefficiency? Are there any significant international differences in the levels of technical efficiency and, if so, how can we reconcile these results with the observed pattern of international trade, etc? As the first in a series of studies on the technical efficiency of Korea's manufacturing industries, this paper attempts to answer some of these questions. Since the estimation of technical efficiency requires the use of plant-level data for each of the five-digit KSIC industries available from the Census of Manufactures, one may consture the findings of this paper as empirical evidence of technical efficiency in Korea's manufacturing industries at the most disaggregated level. We start by clarifying the relationship among the various concepts of efficiency-allocative effciency, factor-price efficiency, technical efficiency, Leibenstein's X-efficiency, and scale efficiency. It then becomes clear that unless certain ceteris paribus assumptions are satisfied, our estimates of technical inefficiency are in fact related to factor price inefficiency as well. The empirical model employed is, what is called, a stochastic frontier production function which divides the stochastic term into two different components-one with a symmetric distribution for pure white noise and the other for technical inefficiency with an asymmetric distribution. A translog production function is assumed for the functional relationship between inputs and output, and was estimated by the corrected ordinary least squares method. The second and third sample moments of the regression residuals are then used to yield estimates of four different types of measures for technical (in) efficiency. The entire range of manufacturing industries can be divided into two groups, depending on whether or not the distribution of estimated regression residuals allows a successful estimation of technical efficiency. The regression equation employing value added as the dependent variable gives a greater number of "successful" industries than the one using gross output. The correlation among estimates of the different measures of efficiency appears to be high, while the estimates of efficiency based on different regression equations seem almost uncorrelated. Thus, in the subsequent analysis of the determinants of interindustry variations in technical efficiency, the choice of the regression equation in the previous stage will affect the outcome significantly.