• Bulletin of the Korean Mathematical Society
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• v.31 no.2
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• pp.210-214
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• 1994

The purpose of this paper is to investigate the relationship between the depths of the Rees algebra R[It] and the associated graded ring g $r_{I}$(R) of an ideal I in a local ring (R,m) of dim(R) > 0. The relationship between the Cohen-Macaulayness of these two rings has been studied extensively. Let (R, m) be a local ring and I an ideal of R. An ideal J contained in I is called a reduction of I if J $I^{n}$ = $I^{n+1}$ for some integer n.geq.0. A reduction J of I is called a minimal reduction of I. The reduction number of I with respect to J is defined by (Fig.) S. Goto and Y.Shimoda characterized the Cohen-Macaulay property of the Rees algebra of the maximal ideal of a Cohen-Macaulay local ring in terms of the Cohen-Macaulay property of the associated graded ring of the maximal ideal and the reduction number of that maximal ideal. Let us state their theorem.m.m.

• Tuberculosis and Respiratory Diseases
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• v.53 no.1
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• pp.36-45
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• 2002

Background : In mammals, the activity of antioxidant enzymes is increased in adult lung to adapt to hyperoxia. The increase of these activities is augmented in neonates and is known as an important mechanism of tolerance to high oxygen levels. Peroxiredoxin(Prx) is an abundant and ubiquitous intracellular antioxidant enzyme. Prx I and II are major cytosolic subtypes. The aim of this study was to examine th Prx I and II mRNA and protein expression levels in adult rat lungs and to compare then with those of neonatal rat lungs exposed to hyperoxia. Materials and Methods : Adult Sprague-Dawley rats and neonates that were delivered from timed pregnant Sprague-Dawley rat were randomly exposed to normoxia or hyperoxia. After exposure to high oxygen level for a set time, the bronchoalveolar lavage fluid and lung tissue were obtained. The Prx I and II protein expression levels were measured by western blot analysis using polyclonal rabbit anti-Prx I or anti-Prx II antibodies and the relative expression of the Prx I and Prx II per Actin protein were obtained as an internal standard. The Prx I and II mRNA expression levels were measured by northernblot analysis using Prx I and Prx II-specific cDNA prepared from pCRPrx I and pCRPrx II, and the relative Prx I and Prx II expression levels per Actin mRNA were obtained as an internal standard. Results : Hyperoxia induced some peak increase in the Prx I mRNA levels after 24 hour in adult rats. Interestingly, hyperoxia induced a marked increase of Prx I mRNA 24 hour in neonatal rats. However, hyperoxia did not induce an alteration in the expression of Prx II mRNA in both the adult and neonatal rat lungs. Hyperoxia did not induce an alteration in the expression of the Prx I and Prx II protein in both the adult and neonatal rat lungs. Hyperoxia did not induce an alteration in the amount of Prx I and Prx II protein all the times in the bronchoalveolar fluid of adult rats. Conclusion : Prx I and II is differently regulated by hyperoxia in adult and neonatal rat lung at the transcriptional level. The prominent upregulation of Prx I mRNA in neonates compared to those in adults by hyperoxia may be another mechanism of resistance to high oxygen levels in neonate.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.6
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• pp.303-306
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• 2003

Metabotropic glutamate receptors (mGluRs), classified into three groups (group I, II, III), play a critical role in modulation of synaptic transmission at central and peripheral synapses. In the present study, extracellular field potential recording techniques were used to investigate effects of mGluR agonists on excitatory synaptic transmission at thalamic input synapses onto the lateral amygdala. The non-selective mGluR agonist t-ACPD ($100{\mu}M$) produced reversible, short-term depression, but the group III mGluR agonist L-AP4 ($50{\mu}M$) did not have any significant effects on amygdala synaptic transmission, suggesting that group I and/or II mGluRs are involved in the modulation by t-ACPD. The group I mGluR agonist DHPG ($100{\mu}M$) produced reversible inhibition as did t-ACPD. Unexpectedly, the group II mGluR agonist LCCG-1 ($10{\mu}M$) induced long-term as well as short-term depression. Thus, our data suggest that activation of group I or II mGluRs produces short-term, reversible depression of excitatory synaptic transmission at thalamic input synapses onto the lateral amygdala. Considering the long-term effect upon activation of group II mGluRs, lack of long-term effects upon activation of group I and II mGluRs may indicate a possible cross-talk among different groups of mGluRs.

• Journal of the Korean Mathematical Society
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• v.38 no.3
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• pp.623-631
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• 2001

Let $\kappa$ be a real abelian field of conductor f and $\kappa$(sub)$\infty$ = ∪(sub)n$\geq$0$\kappa$(sub)n be its Z(sub)p-extension for an odd prime p such that płf$\phi$(f). he aim of this paper is ot compute the cohomology groups of circular units. For m>n$\geq$0, let G(sub)m,n be the Galois group Gal($\kappa$(sub)m/$\kappa$(sub)n) and C(sub)m be the group of circular units of $\kappa$(sub)m. Let l be the number of prime ideals of $\kappa$ above p. Then, for mm>n$\geq$0, we have (1) C(sub)m(sup)G(sub)m,n = C(sub)n, (2) H(sup)i(G(sub)m,n, C(sub)m) = (Z/p(sup)m-n Z)(sup)l-1 if i is even, (3) H(sup)i(G(sub)m,n, C(sub)m) = (Z/P(sup)m-n Z)(sup l) if i is odd (※Equations, See Full-text).

• Communications of the Korean Mathematical Society
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• v.17 no.4
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• pp.719-729
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• 2002

Consider the random n $\times$ m assignment problem with m $\geq$ $_{i,j}$ Let $u_{i,j}$ be iid uniform random variables on [0, 1] and exponential random variables with mean 1, respectively, and let $U_{n, m}$ and $T_{n, m}$ denote the optimal assignment costs corresponding to $u_{i, j}$ and $t_{i, j}$. In this paper we first give a comparison result about the discrepancy E $T_{n, m}$ -E $U_{n, m}$. Using this comparison result with a known lower bound for Var( $T_{n, m}$) we obtains a lower bound for Var( $U_{n, m}$). Finally, we study the way that E $U_{n, m}$ and E $T_{n, m}$ vary as m does. It turns out that only when m - n is large enough, the cost decreases significantly.tly.

• Applied Chemistry for Engineering
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• v.32 no.1
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• pp.10-14
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• 2021

mCherry is one of the well-understood red fluorescent proteins which has a similar tertiary structure as GFPs, but pH resistant due to the lack of hydrogen bond network. Whereas mCherry-I202T showed far-red fluorescence and also pH sensitive property because of the additional hydrogen bond formed by substituting Ile of 202 amino acid sequence on mCherry with Thr. In order to verify the pH sensitive characteristic of mCherry-I202T owing to the extension of hydrogen bond, UV-vis spectrum was measured over the range of acidic to basic pH. We also demonstrate further possibilities of applying mCherry-I202T as a pH sensor.

• YAKHAK HOEJI
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• v.41 no.5
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• pp.615-621
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• 1997

Dehydropeptidase-I (DHP-I) was solubilized from porcine kidney by treatment with n-butanol and partially purified 19.25 fold by $(NH_4)_2SO_4$ precipitation, DEAE-Sepharose CL-6B ion exchange chromatography and Sephacryl S-300 HR chromatography with an overall yield of 19.16. DHP-I showed its optimal activity at pH 7.5 and 25$^{\circ}C$. Its activity was stable under neutral and alkaline conditions, but was disappeared under acidic condition. And DHP-I was heat-labile and its activity remained at 45$^{\circ}C$ for 3hrs. The enzyme was not inhibited by dicationic ions, while its activity was increased by $Co^{2+}$(1mM) and $Zn^{2+}$ (0.1mM). The enzyme was inhibited by EDTA and N-ethylmaleimide. The relative molecular mass of DHP-I was estimated to be approximately 100kDa by gel filtration chromatography. The $K_m$ value of DHP-I for glycyldehydrophenylalanine (GDHP) was 1.98mM. DWP20418 [(1R, 5S, 6S)-6-[1-(R)-Hydroxyethyl]-1-methyl-2-[(2S, 4S)-2-(piperazinylcarbonyl)-1-(R)-hydroxyethyl)pyrrolidine-4-thio]carbapen-2-em-3-carboxylic acid], compared with meropenem (MEPM), was rather easily hydrolized by DHP-I, while it was four times more resistant than imipenem (IPM) to DHP-I.

• Journal of the Chungcheong Mathematical Society
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• v.29 no.2
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• pp.229-253
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• 2016

As a generalization of (i, j)-weakly m-continuous functions [43], we introduce the notion of weakly M(i, j)-continuous functions and obtain many characterizations and some properties of the functions. We show that the function is a unified form of some functions between m-spaces and certain kinds of weakly continuous functions in bitopological spaces.

• Journal of the Korean Society of Costume
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• v.51 no.4
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• pp.43-56
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• 2001

Articles on fashion of major daily newspapers for about one years after I.M.F. system were analyzed. The influence of I.M.F. system, values, the importance of costumes at economic crisis were studied through fashion at that time. The major conclusions of the study are as follows : 1. Costumes made in Korea, national brands In Korean words, practical styles, multi-functional design, economic tastes and mixed fashions were emphasized. 2. The sound and patriotic values were pursued through domestic fashion and creative ideas were developed to overcome economic crisis. 3. The meaning of costumes was still important under shrink of consumption. Costumes were useful tools to estimate ability and express aesthetic appreciation. The sound fashion trends under I.M.F. system reflect the reflection on overconsume and the will to overcome economic crisis. Such trends should be fixed for the establishment of economic prosperity for the nation.

• Bulletin of the Korean Mathematical Society
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• v.61 no.3
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• pp.717-734
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• 2024

Let R be a commutative ring with identity and m, n be positive integers. In this paper, we introduce the class of weakly (m, n)-prime ideals generalizing (m, n)-prime and weakly (m, n)-closed ideals. A proper ideal I of R is called weakly (m, n)-prime if for a, b ∈ R, 0 ≠ a^mb ∈ I implies either aⁿ ∈ I or b ∈ I. We justify several properties and characterizations of weakly (m, n)-prime ideals with many supporting examples. Furthermore, we investigate weakly (m, n)-prime ideals under various contexts of constructions such as direct products, localizations and homomorphic images. Finally, we discuss the behaviour of this class of ideals in idealization and amalgamated rings.