• Applied Biological Chemistry
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• v.39 no.1
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• pp.70-76
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• 1996

A series of the herbicidal pyridylsulfonyl areas, none substitutent, 1-(4,6-dimethoxypyrimidine-2-yl)-3-(2-pyridylsulfonyl) urea, 3 and 3-trifluoromethyl substitutent, 1-(4,6-dimethoxypyrimidine-2-yl)-3-(3-trifluoromethyl-2-pyridylsulfonyl) urea, 5(Flazasulfuron) were synthesizied and the rate of hydrolysis of their has been studied in 25%(v/v) aqueous dioxane at $45^{\circ}C$. From the results of solvent effect($m{\ll}1,\;n{\ll}3\;&\;{\mid}m{\mid}{\ll}{\mid}{\ell}{\mid}$), thermodynamic parameter (${\Delta}S^{\neq}=0.54{\sim}\;-2.19\;e.u.\;&\;{\Delta}H^{\neq}=0.025\;Kcal.mol.^{-1}$), hydrolysis product analysis, $pK_a$ constant(3: 4.9 & 5: lit.4.6) and the rate equation, a marked difference in the kinetics of the reaction of 3 and 5(Flazasulfuron) was observed. It may be concluded that the hydrolysis of 5 proceeds through the $A-S_N2Ar$ reaction via conjugate acid$(5H^+)$ below pH 7.0, whereas, above pH 9.0, the hydrolysis proceeds through irreversibly $(E_1)_{anion}$ and reversibly $(E_1CB)_R$ mechanism via conjugate base(CB), respectively. But in case of 5, $A-S_N2Ar,\;(E_1)anion\;and\;(E_1CB)_R$ mechanism involved Smile rearrangement. The mate of rearrangement of 5 to a 3-trifluoromethyl-2-pyridylpyrimidinyl urea(PPU) in acid and 3-trifluoromethyl-2-pyridyl-4.6-dimethoxypyridinyl amine (PPA) in base was increased about 3.5 times by the introduction of trifluoromethyl group in the 3-position on the 2-pyridyl ring. From the basis of these findings, a possible mechanism for the hydrolysis of 5 was proposed and discussed.

• Korean Journal of Ichthyology
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• v.8 no.2
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• pp.74-83
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• 1996

The ultrastructure of the spermatozoa of the family Cobitidae, 6 genera and 12 species, was examinated under electron microscopes. Spermatozoa of the observed species consist of a head(nucleus), a short midpiece, and a single tai1(flagellum). It is of anacrosomal aquasperm type, lacking an acrosome. However, the spermatozoa of Nemacheilus toni has vestigal acrosome or acrosome-like vesicle in the anterior region of the nucleus during spermiogenesis, The nucleus of Cobitidae is approximately spherical except that N. toni is conic. The mid piece was under $3.0{\mu}m$ in length and contained 5-8 ring-shaped mitochodria. Genera Cobitis, Iksookimia, Niwaella, and Nemacheilus. have shorter midpiece, whereas Misgurnus and Lefua have longer midpiece. The flagellum was uniflagellate consisting of a typical 9+2 axoneme without fins.

• Korean Journal of Applied Biomechanics
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• v.22 no.4
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• pp.387-394
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• 2012

The purpose of this study was to compare and analyze the finger pressure and kinematic variables in the forehand hairpin net shot between skilled elite players and less skilled recreational players. Eight elite players(age: $18.1{\pm}0.8yrs$, height: $176.8{\pm}1.5cm$, weight: $640.9{\pm}48.6N$) with minimum of 6 years of experience and eight recreational players(age: $27.9{\pm}1.6yrs$, height: $177.1{\pm}6.1cm$, weight: $820.5{\pm}62.8N$) with less than one year experience were recruited in this study. For each trial being analyzed, four critical instants were identified from the video recordings: Right heel contact1 (E1), Right toe-off (E2), Right heel contact2 (E3), and Shuttlecock Impact (E4). Each hairpin net shot was broken into consecutive phases: E1~E2 (Right Landing Phase: RLP), E2~E3 (Sliding Step Phase: SSP), and E3~E4 (Impact Phase: IP). Temporal parameters, shuttlecock speed, linear and angular kinematics of body segments, and finger pressures were computed for this study. The results showed that The finger pressure of the ring finger and the middle finger for the skilled group during an impact had significantly greater than those of unskilled group. It is possible that all fingers were not used in the same manner when the racket was gripped in forehand hairpin. The result also suggested that the ring finger and the middle finger pushed the racket from top to bottom while having the mid-phalanx and proximal phalanx of index finger as an axis.

• Journal of Conservation Science
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• v.37 no.2
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• pp.154-166
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• 2021

The royal seal, in either gold or jade, is used to symbolize Joseon's royal family, and it is made up of a Bonu (a handle), Bosin (a body), Bomun (a letter inscribed on the seal), and Bosu (a string attached to the seal). The Bosu was designed to enhance the seal's dignity and facilitate convenient handling. Bosu consists of Kkeun-mog and Bangwool-sul (decorated with gilt paper), which are made of Bangwool, Bangwool-mog, and Sul. In this study, the form survey, color, material, and composition of 318 Bosu pieces from the Joseon Dynasty and Korean Empire produced from 1441 to 1928 were analyzed. As time passed, the strings on the seals became longer and thinner. Bangwool-mog disappeared from the mid-1800s, and a ring appeared at the end of the Sul. Most of the colors used were scarlet, but orange and purple were also identified. Although most of the Bosu are silk, five Bosu from the 1900s and one Bosu from the 1740s (likely replaced in the 1900s) are estimated to be rayon. The gilt paper's main chemical components used to decorate the Bangwool-sul vary according to age. Until the mid-1800s, gold (Au) was used for the Sul and Bangwool, but since the mid-1800s, gold (Au) and brass (Cu-Zn) were used for Sul and Bangwool, respectively, and then brass (Cu-Zn) was used for Sul and Bangwool. While the Bosu was a seal accessory, it can be used to identify changes in the manufacturing techniques and materials of the period.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.35-41
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• 2015

The age and growth of the Marbled sole, Pleuronectes yokohamae were investigated using left sagittal otoliths of 832 individuals collected in the mid-southern waters of Korea from January 2006 to April 2007. The seasonal changes in the ratio of an translucent zone to interval between annular rings revealed that the boundaries between translucent and opaque parts of the otolith were annual growth rings formed between May and June once a year. The spawning period was November to March and therefore the duration from fertilization to the complete formation of the annual growth ring became fifteen months. The parameters of von Bertalanffy growth equations estimated using the average standard length at each age are the $L_{\infty}$ of 48.04cm, K of 0.1406/year and $t_0$ of -0.5116 for female and 26.14cm, 0.3056/year and -0.8202 for male, respectively. Finally, it is suggested that the growth of female is faster than that of male from age-2.

• Journal of the Korean Mathematical Society
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• v.54 no.6
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• pp.1733-1757
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• 2017

Let $R={\oplus}_{{\alpha}{\in}{\Gamma}}R_{\alpha}$ be an integral domain graded by an arbitrary torsionless grading monoid ${\Gamma}$, ${\bar{R}}$ be the integral closure of R, H be the set of nonzero homogeneous elements of R, C(f) be the fractional ideal of R generated by the homogeneous components of $f{\in}R_H$, and $N(H)=\{f{\in}R{\mid}C(f)_v=R\}$. Let $R_H$ be a UFD. We say that a nonzero prime ideal Q of R is an upper to zero in R if $Q=fR_H{\cap}R$ for some $f{\in}R$ and that R is a graded UMT-domain if each upper to zero in R is a maximal t-ideal. In this paper, we study several ring-theoretic properties of graded UMT-domains. Among other things, we prove that if R has a unit of nonzero degree, then R is a graded UMT-domain if and only if every prime ideal of $R_{N(H)}$ is extended from a homogeneous ideal of R, if and only if ${\bar{R}}_{H{\backslash}Q}$ is a graded-$Pr{\ddot{u}}fer$ domain for all homogeneous maximal t-ideals Q of R, if and only if ${\bar{R}}_{N(H)}$ is a $Pr{\ddot{u}}fer$ domain, if and only if R is a UMT-domain.

• Journal of the Korean Mathematical Society
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• v.51 no.2
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• pp.239-250
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• 2014

Let R be a commutative Noetherian (not necessarily local) ring, I an ideal of R and M a finitely generated R-module. In this paper, by computing the local cohomology modules and Ext-modules via the injective resolution of M, we proved that, if for an integer t > 0, dim$_RH_I^i(M){\leq}k$ for ${\forall}i$ < t, then $$\displaystyle\bigcup_{i=0}^{j}(Ass_RH_I^i(M))_{{\geq}k}=\displaystyle\bigcup_{i=0}^{j}(Ass_RExt_R^i(R/I^n,M))_{{\geq}k}$$ for ${\forall}j{\leq}t$ and ${\forall}n$ >0. This shows that${\bigcup}_{n>0}(Ass_RExt_R^i(R/I^n,M))_{{\geq}k}$ is a finite set for ${\forall}i{\leq}t$. Also, we prove that $\displaystyle\bigcup_{i=1}^{r}(Ass_RM/(x_1^{n_1},x_2^{n_2},{\ldots},x_i^{n_i})M)_{{\geq}k}=\displaystyle\bigcup_{i=1}^{r}(Ass_RM/(x_1,x_2,{\ldots},x_i)M)_{{\geq}k}$ if $x_1,x_2,{\ldots},x_r$ is M-sequences in dimension > k and $n_1,n_2,{\ldots},n_r$ are some positive integers. Here, for a subset T of Spec(R), set $T_{{\geq}i}=\{{p{\in}T{\mid}dimR/p{\geq}i}\}$.

• Molecules and Cells
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• v.43 no.1
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• pp.76-85
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• 2020

MARCH5 is a RING finger E3 ligase involved in mitochondrial integrity, cellular protein homeostasis, and the regulation of mitochondrial fusion and fission. To determine the function of MARCH5 during development, we assessed transcript expression in zebrafish embryos. We found that march5 transcripts were of maternal origin and evenly distributed at the 1-cell stage, except for the mid-blastula transition, with expression predominantly in the developing central nervous system at later stages of embryogenesis. Overexpression of march5 impaired convergent extension movement during gastrulation, resulting in reduced patterning along the dorsoventral axis and alterations in the ventral cell types. Overexpression and knockdown of march5 disrupted the organization of the developing telencephalon and diencephalon. Lastly, we found that the transcription of march5 was tightly regulated by the transcriptional regulators CHOP, C/EBPα, Staf, Znf143a, and Znf76. These results demonstrate the essential role of March5 in the development of zebrafish embryos.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3696-3701
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• 2011

The single-crystal structure of partially dehydrated partially $Mg^{2+}$-exchanged zeolite Y, ${\mid}Mg{30.5}Na_{14}(H_2O)_{2.5}{\mid}$ [$Si_{117}Al_{75}O_{384}$]-FAU per unit cell, ${\alpha}$ = 25.5060(1) ${\AA}$, dehydrated at 723 K and $1{\times}10^{-4}$ Pa, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd$\bar{3}$ m at 100(1) K. The structure was refined using all intensities to the final error indices (using only the 561 reflections with $F_{\circ}$ > $4{\sigma}(F_{\circ})$) $R_1$ = 0.0377 (Based on F) and $R_2$ = 0.1032 (Based on $F^2$). About 30.5 $Mg^{2+}$ ions per unit cell are found at four different crystallographic sites. The 14 $Mg^{2+}$ ions occupy at site I at the center of double 6-ring (Mg-O = 2.231(3) ${\AA}$, O-Mg-O = $89.15(11)^{\circ}$ and $90.85(11)^{\circ}$). Four $Mg^{2+}$ ions are found at site I' in the sodalite cavity; the $Mg^{2+}$ ions are recessed 1.22 ${\AA}$ into the sodalite cavity from their 3-oxygen plane (Mg-O = 2.20(3) ${\AA}$ and O-Mg-O = $92.3(14)^{\circ}$). Site II' positions (opposite single 6-rings in the sodalite cage) are occupied by 2.5 $Mg^{2+}$ ions, each coordinated to an $H_2O$ molecule (Mg-O = 2.187(20) ${\AA}$ and O-Mg-O = $114.2(16)^{\circ}$). The 10 $Mg^{2+}$ ions are nearly three-quarters filled at site II in the supercage, being recessed 0.12 ${\AA}$ into the supercage (Mg-O = 2.123(4) A and O-Mg-O = $119.70(19)^{\circ}$). About 14 $Na^+$ ions per unit cell are found at one crystallographic site; the $Na^+$ ions are located at site II in the supercage (Na-O = 2.234(7) ${\AA}$ and O-Mg-O = $110.5(4)^{\circ}$).

• Parasites, Hosts and Diseases
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• v.32 no.3
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• pp.195-200
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• 1994

Malaria is estimated to have a worldwide incidence of more than 100 million clinical cases and approximately 1 miuion deaths per year. Korea, although previously tnlown as an endemic area of tertian malaria (Pzosmonin vivax), has been considered free from malaria as there had been no report on indigenous cases since 1984. Recently, however, we experienced an indigenous case of P. viuax infection in a young man who had never been abroad. The patient was a 23-year-old Korean soldier with 18-day history of recurrent fever and chill lasting 4 to 8 hours on alternative days since mid-July 1993. He had lived in Changwon, Hyongsangnam-do, before entering barracks located in Paiu-gun, Kyonggj-do on Jne 1992, and had never been out of Korea. He had no history of blood transfusion nor parenteral use of drugs. The peripheral blood smears showed typical ring forms, trophozoites, and gametocytes of p. uiuox, in addition to mild anemia and thrombocytopenia. After confirmation of the diagnosis, he was treated with hydroxychloroquine and primaquine. Follow-up blood smears no more revealed malaria parasites. It is not certain whether the present case is due to a resurgence of indigenous malaria or a secondary infection from introduced mnuia. Whichever the source of infection the domestic occurrence of mnuia cycle in Korea should be a warning sign in public health point of view.