• Korean Journal of Animal Reproduction
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• v.12 no.1
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• pp.24-30
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• 1988

These experiments were carried out to develop new techniques for In Vitro separatin of X-and Y-bearing spermatozoa. The bull semen was applied to the various Gel-Columns filled with swellen Sephadex G-50 Fine and then elutriated wtih Locke solution (elutriation rate; 1ml/3-4min., 1ml/1-2min.). Elutriated solution was fractionated into 1ml by automatic Fraction Collector and spermatozoa included in each fraction were subjected to the estimation of viability and recovery rate, and to B-body test. The results obtained in these experiments were summarized as follows: 1. When the column size and the elutriation rate were adjusted to 15$\times$1.6cm and 1ml/3-4min., respectively, the highest sperm concentration was obtained from the 8th to the 12th fraction. 2. As a trend, the viability of spermatozoa was improved by chromatography, and the degree of improvement ranged 5 to 10 percentage. 3. The average recovery rate of spermatozoa applied to column was 73.2 percentage and ranged 52.6 to 81.3 percentage. 4. The lowest rate of B-body bearing spermatozoa following chromatography was obtained when the column size and the elutriation rate were adjusted to 15$\times$0.8cm and 1ml/1-2min., respectively.

• The Korean Journal of Pharmacology
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• v.10 no.1 s.15
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• pp.47-52
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• 1974

The isolated rabbit gall bladder strips were prepared according to the technique described by Amer and Becvar (1969). The strips were placed in a bath containing 100 ml of Locke-Ringer solution maintained at $38^{\circ}C$. Oxygen was continuously bubbled through the solution. The tension of the muscle strip was initially adjusted to 0.7g. The contractile response was measured isometrically by a force-displacement transducer connected to a polygraph. The effect of a number of autonomic drugs were studied for their interaction with caerulein (Prof. V. Erspamer, F.I. 6934 Caerulein, Farmitalia, Italia), a gastrin or CCK.PZ like peptide, on isolated rabbit gall bladder strips. In this preparation caerulein produced contractions of CCK-PZ type, but the relative potency on a weight basis was 40 times that of CCK-PZ. The response of caerulein was not modified by either cholinergic or alpha or beta adrenergic blockade. However, the response of caerulein and of barium on the strips were prevented by papaverine or aminophylline. Isoproterenol, papaverine or aminophylline alone relaxed the preparation whereas caerulein, CCK-PZ, acetylcholine, serotonin, histamine or barium chloride contracted the preparation. In summary, it is concluded that caerulein on the gall bladder strip seems to act independently of the autonomic nervous system and mediated via mechanisms apparently similar to those involved in the action of barium chloride.

• The Korean Journal of Pharmacology
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• v.13 no.2
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• pp.49-59
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• 1977

Adrenergic receptors are now classified into alpha type and beta type These adrenergic receptors are distributed in various tissue in different patterns. Therefore, the adrenergic response of a certain tissue may be different from those of the other tissues, and such differences may exist among various species of animals. In this paper, the authors attempt to reevaluate the effect of epinephrine on the isolated atria, aortic strips, and vas deferenses of rabbits preincubated with alpha receptor blockades (ergotamine and dibenamine) and beta receptor blockades (propranolol and dichloroisoproterenol) in Locke-Ringer bathing medium. The results obtained were summarized as follows; 1) The dose dependent responses of isolated atria to epinephrine were significantly inhibited by propranolol and dichloroisoproterenol, and slightly inhibited by dibenamine, but not affected by ergotamine. 2) The dose dependent responses of excised aortic strips to epinephrine were significantly inhibited by ergotamine and dibenamine, but the responses were slightly potentiated by propranolol, and significantly by dichloroisoproterenol. 3) The dose dependent responses of isolated vas deferenses to epinephrine were significantly inhibited by ergotamine and dibenamine, but slightly potentiated by propranolol and dichloroisoproterenol.

• Journal of Educational Research in Mathematics
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• v.8 no.2
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• pp.405-423
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• 1998

This study aims to reflect the origin and the meaning of open education and to derive pedagogical principles for open mathematics education. Open education originates from Socrates who was the founder of discovery learning and has been developed by Locke, Rousseau, Froebel, Montessori, Dewey, Piaget, and so on. Thus open education is based on Humanism and Piaget's psychology. The aim of open education consists in developing potentials of children. The characteristics of open education can be summarized as follows: open curriculum, individualized instruction, diverse group organization and various instruction models, rich educational environment, and cooperative interaction based on open human relations. After considering the aims and the characteristics of open education, this study tries to suggest the aims and the directions for open mathematics education according to the philosophy of open education. The aim of open mathematics education is to develop mathematical potentials of children and to foster their mathematical appreciative view. In order to realize the aim, this study suggests five pedagogical principles. Firstly, the mathematical knowledge of children should be integrated by structurizing. Secondly, exploration activities for all kinds of real and concrete situations should be starting points of mathematics learning for the children. Thirdly, open-ended problem approach can facilitate children's diverse ways of thinking. Fourthly, the mathematics educators should emphasize the social interaction through small-group cooperation. Finally, rich educational environment should be provided by offering concrete and diverse material. In order to make open mathematics education effective, some considerations are required in terms of open mathematics curriculum, integrated construction of textbooks, autonomy of teachers and inquiry into children's mathematical capability.

• The Korean Journal of Pharmacology
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• v.16 no.1 s.26
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• pp.35-39
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• 1980

In this study, the effects of phenoxybenzamine and related drugs on the action of CCK-PZ and caerulein were examined in isolated gall bladder of guinea pig and higher esophagus strip of fowl. The strips were placed in a bath containing Locke-Ringer solution maintained at $38^{\circ}C$. Oxygen was continuously bubbled through the solution. The contractile response was measured isometrically by a force displacement transducer connected to polygraph. In isolated gall bladder preparation caerulein produced contractile response of CCK-PZ type, but the relative potency on a weight basis was 30 times stronger than CCK-PZ. The response of caerulein or CCK-PZ was not blocked by cholinergic blocking agent and both alpha and beta adrenergic blockades, however, the response of caerulein or CCK-PZ was exceptionally blocked by phenoxybenzamine. In isolated esophagus strip CCK-PZ with high concentration produced marked contraction which was not modified by atropine and other blocking agents, whereas the response was blocked by phenoxybenzamine. These results lead to the conclusion that phenoxybenzamine inherently inhibits the contractile response of CCK-PZ and caerulein on esophagus and other smooth muscle.

• The Korean Journal of Pharmacology
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• v.11 no.1 s.17
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• pp.15-18
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• 1975

The effect of skin extracts of Korean amphibian, poisonous snake and fresh-water fish were determined for their caerulein-like action on rabbit gall bladder strips. The isolated gall bladder strips were prepared according to the technique described by Amer and Becvar(1969). The strips were placed in a bath containing 100ml of Locke-Ringer solution maintained at $38^{\circ}C$. Oxygen was continuously bubbled through the solution. The tension of the muscle strip was initially adjusted to 0.7g. The contractile response was measured isometrically by a force-displacement transducer connected to a polygraph. In this rabbit gall bladder strip caerulein produced contraction of CCK-PZ type. The skin extract of Korean amphibian also elicited similar contraction as caerulein, which extracted from Australian amphibian, Hyla caerulea, by Erspamer et al. The calculated amount was approximately $2{\mu}g$ caerulein per gram of skin tissue in Korean amphibian and the potency was about 1/200 of that seen in Australian amphibian. The contraction of gall bladder strip by our amphibians occurs in decreasing order; Rana Nigromaculata coreana Okada, Rana nigromaculata Hallowell, Hyla arborea japonica Gunther and Bombina orientalis Boulenger. The skin extracts of poisonous snake and fresh-water fish produced no caerulein-like activity.

• Journal of English Language & Literature
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• v.58 no.6
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• pp.1103-1117
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• 2012

This paper focuses on eighteenth-century English pastor, poet, and hymnist, Isaac Watts (1674-1748), a significant yet neglected nonconformist dissenter, who defines a public religion and transforms poetry as a new literary political genre. During England's post-Revolutionary religio-political turmoil, Watts's poem, "The Hurry of the Spirits, in a Fever and Nervous Disorders" (1734), deliberately engages in a methodical refusal to settle upon a single system of images or terms for describing or referring to the speaker's identity or situation. Watts's, literal and metaphoric, refusal to identify with one religio-political approach to nonconformist dissent has been the very point of criticism that not only undermines the poet's monumental work on hymns but also the lasting impact that the poet had upon England's national consciousness. This study, therefore, questions why the poet refuses to choose one ideal path in his pursuit for religious freedom and, further, analyzes how the hymn writer defends his demotic aesthetics. This paper investigates Watts's comprehensive and detailed formulation of what a secularized "social religion" should entail and, further, explores its beneficial role in the pursuit for society's peace. In contrast to Milton's apocalyptic vengeance, Watts's nonconformist goal seeks to balance and locate authority in the individual with the ancient ideal of a "sacred order" that is represented in "The Hurry of the Spirits" through the means of poetic imagination.

• Journal of the Korean Society of Costume
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• v.39
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• pp.139-166
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• 1998

This dissertation is to help understanding about the emergence of active children's clothes in the latter part of the 18th century in England. In previous ages children had not been look-ed upon as children, but as incomplete and in-ferior men and women, the costume of children had not been distinguishable from that of their elders. The early eighteenth-century chil-d could not play in comfort because they dressed like their parents. But in the third quarther of the eighteenth century children became free from their con-comfortable and became active. English chil-dren's clothes was prevailing even in Europe as well. In the background of this liberation, there were many enlightened ideas, such as philosophers of enlightenment, doctors, writers, educators. Among these John Locke and Jean Jacque Rousseau criticized openly about rampant fashion which was distorting the body by corset and hoop. Rousseau was the one who wrote$\boxDr$Emile$\boxUl$and played the most important role to free children from an old fashioned idea, and emphasized to bring up children by the natural process of mental and physical development as human beings are a part of nature. Fashion reflects politic, economic, social, ideology, culture of the days and these factor function to create fashion which shows“Time Spirit”.Children's clothes, like those of their parents, follow the fashion, but with a difference, the form of which varies with the attitude to the child. Thus this dissertation was to study in relation with the background of the times in the latter part of 18th century in England and Rousseau's Naturalism in connection with the emergence of active children's clothes. The result is that diffusion of the idea of freedom and equality, the growth of bourgeoisie, the development of clothing and tex-tile industry have influenced to the emergence of active children's clothes. Also a great deal of middle and high class parents devoted to their children's education and was influenced by Rousseau's Naturalism. Specially the bourgeoisie who made their fortune by their own effort were eager to educate their achievement and business by their children through education. This factor influenced to the children's clothes as well.

• The Korean Journal of Physiology
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• v.9 no.1
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• pp.69-76
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• 1975

Cardiac performances were analyzed in intact turtle heart(Amyda japonica), perfusing with turtle Ringer-Locke's solution containing various hydrogen ion concentration, at several levels of arterial and venous pressure. 1. Ventricular work increased when venous pressure, or venous filling pressure increased, and also increased when arterial pressure increased. 2. The higher the arterial pressure, the lower the cardiac to output, for arterial pressure is the resistance to the ventricular blood flow. On the other hand, in specific arterial pressure, cardiac output was proportional to the venous filling pressure. 3. Heart rates did not change significantly during the perfusion with Ringel· solution of various pH. 4. In the heart Perfused with Ringer solution of various pH, ventricular work was the highest at PH 7.6 (at 6 $cmH_2O$ arterial pressure and 8 $cmH_2O$ venous pressure, the ventricular work was 63.09m$\cdot$cm). However, within the range of pH $7.1{\sim}7.6$, there were no significant changes in cardiac output and ventricular work. Below the level of pH 7.0, ventricular work decreased to less than 56% of maximium value (at $6cmH_2O$ arterial pressure and $8cmH_2O$ venous Pressure, ventricular work was 36.0$gm{\cdot}$ at pH 7.0). At pH 7.7 ventricular work decreased to less than 48% of maximum value (ventricular work: 30.0 $gm{\cdot}$). The nature of the cardiac performance at the various arterial and venous pressures was similar to that of normal heart. 5. Turtle heart seemed to be relatively insensitive to acid-base disturbances. The mechanism of negative inotropic effect of hydrogen ion was discussed.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.5
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• pp.82-87
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• 2008

This paper presents a new fast locking dual-slope phase-locked loop. The conventional dual-slope phase-locked loop consists of two charge pumps and two phase-frequency detectors. In this paper, the dual-slope phase-locked loop was achieved with a charge pump and a phase-frequency detector as adjusting a current of the charge pump according to the phase difference. The proposed circuit was verified by HSPICE simulation with a $0.35{\mu}m$ CMOS standard process parameter. The phase locking time of the proposed dual-slope phase-locked loop was $2.2{\mu}s$ and that of the single-slope phase-locke loop was $7{\mu}s$.