• 대한수의학회지
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• 제47권3호
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• pp.273-279
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• 2007

Swine influenza is an acute, infectious respiratory disease caused by type A influenza viruses in pigs. In the previous studies, serological surveys have indicated the presence of H3N2 swine influenza virus (SIV) since 1995 in Korea. And the percentage of the antibody-positive rate was 39.12% in the survey determining the prevalence of H1N1 SIV antibodies in 2002. The purpose of this study was therefore to investigate the sero-prevalence of SIV regard to the age of the pig and the season between June 2004 and May 2005. In this study, a total of 932 sera were used. These sera were randomly selected from blood samples, which were submitted to Department of Veterinary Pathology, Kangwon National University and Department of Veterinary Virology, Seoul National University from June 2004 to May 2005. These sera have been tested by ELISA test kit (IDEXX Lab, USA) for the SIV H3N2, H1N1 respectively. SAS version 9.1 was used for the statistical analysis based on the age of the pig and the season. The overall sero-prevalence of the antibody against H3N2 SIV was 20.82% (194/932). The overall sero-prevalence of the antibody against H1N1 SIV was 37.23% (347/932). The overall dual sero-prevalence of the antibody against H3N2 and H1N1 SIV was 10.62% (99/932). H3N2 has significant difference in statistically regarding the age of the pig and the season (p<0.0001). H1N1 has significant difference in statistically regarding the age of the pig (p<0.0001) but has not significant difference in statistically regarding the season (p=0.5882).

• Bulletin of the Korean Chemical Society
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• 제11권1호
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• pp.22-25
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• 1990

The condensation of 1-amino-1,2-dihydro-3,6-pyridazinedione (1) and 2-amino-2,3-dihydro-1,4-phthalazinedione (2) with mesityl oxide or 3-penten-2-one in acetic acid-ethanol (1:1) gave 3,4,6,9-tetrahydro-6,9-dioxopyridazino[1,2-a][1,2, 3]triazines (9,11) and 3,4,6,11-tetrahydro-6,11-dioxo[1,2,3]triazino[1,2- b]phthalazines (10,12), respectively. The condensation of 1 and 2 with crotonaldehyde, cinnamaldehyde or acrylaldehyde under the same reaction condition gave only N-alkylidene derivatlives (3-8). When the N-alkylidene derivatives isolated from the reaction of 1 and 2 with crotonaldehyde and cinnamaldehyde (3-6) were refluxed in acetic acid, the corresponding heterocyclic compounds (13-16) were obtained.

• Toxicological Research
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• 제5권2호
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• pp.151-166
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• 1989

This study was carried out to investigate the effect of red ginseng extract on development of pepsinogen 1 decrased pyloric glands in experimental stomach carcinogenesis in Sprague-Dawley male rats. Sequential quantitative analyses (by ABC immunohistochemical staining) were made of pepsinogen 1 decreased pyloric glands (PDPG) after treating rats first with a single dose (160 mg/kg) N-methyl-N'-nitrosoguanidine (MNNG) and then with N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) (100ug/ml of drinking water) as a second gastric carcinogen (or promoter).

• 대한수학회논문집
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• 제10권2호
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• pp.409-417
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• 1995

We consider the $R^k$-valued $(k \geq 1)$ process ${X_n}$ generated by $X_n + 1 = f(X_n)+e_{n+1}$, where $f(x) = (h(x),x^{(1)},x^{(1)},\cdots,x{(k-1)})'$. We assume that h is a real-valued measuable function on $R^k$ and that $e_n = (e'_n,0,\cdot,0)'$ where ${e'_n}$ are independent and identically distributed random variables. We obtained a practical criteria guaranteeing a given process to be geometrically ergodic. Sufficient condition for transience is also given.

• Bulletin of the Korean Chemical Society
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• 제18권11호
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• pp.1158-1161
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• 1997

The potentiometric methods have been used to determined the protonation constants (logKiH) for the synthesized 1,7,13-trioxa-4,10,16-triazacyclooctadecane-N,N',N''-tri(methylacetic acid) [N3O3-tri(methylacetic acid)] and the stability constants (logKML) of the complexes of divalent and trivalent metal ions with the ligand N3O3-tri(methylacetic acid). The protonation constants of N3O3-tri(methylacetic acid) were 9.70 for logK1H, 9.18 for logK2H, 7.27 for logK3H, 3.38 for logK4H, and 2.94 for logK5H. The stability constants for the complexes of divalent metal ions with N3O3-tri(methylacetic acid) were 10.39 for Co2+, 10.68 for Ni2+, 13.45 for Cu2+, and 13.00 for Zn2+. The order of the stability constants for the complexes of the divalent metal ions with N3O3-tri(methylacetic acid) was Co2+ < Ni2+ < Zn2+ < Cu2+. The stability constants for the complexes of trivalent metal ions with N3O3-tri(methylacetic acid) were 16.20 for Ce3+, 16.40 for Eu3+, 16.27 for Gd3+, and 15.80 for Yb3+. The results obtained in this study were compared to those obtained for similar ligands, 1,7-dioxa-4,10,13-triazacyclopentadecane-N,N',N"-tri(methylacetic acid) and 1,7,13-trioxa-4,10,16-triazacyclooctadecane-N,N',N"-triacetic acid, which have been previously reported.

• 대한수학회논문집
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• 제30권3호
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• pp.239-252
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• 2015

Motivated mainly by certain interesting extensions of the ${\tau}$-hypergeometric function defined by Virchenko et al. [11] and some ${\tau}$-Appell's function introduced by Al-Shammery and Kalla [1], we introduce here the ${\tau}$-Lauricella functions $F_A^{(n),{\tau}_1,{\cdots},{\tau}_n}$, $F_B^{(n),{\tau}_1,{\cdots},{\tau}_n}$ and $F_D^{(n),{\tau}_1,{\cdots},{\tau}_n}$ and the confluent forms ${\Phi}_2^{(n),{\tau}_1,{\cdots},{\tau}_n}$ and ${\Phi}_D^{(n),{\tau}_1,{\cdots},{\tau}_n}$ of n variables. We then systematically investigate their various integral representations of each of these ${\tau}$-Lauricella functions including their generating functions. Various (known or new) special cases and consequences of the results presented here are also considered.

• Kyungpook Mathematical Journal
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• 제50권1호
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• pp.153-164
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• 2010

We study the global asymptotic stability, the character of the semicycles, the periodic nature and oscillation of the positive solutions of the difference equation $x_{n+1}=\frac{p+x_{n-k}}{q+x_n}+\frac{x_{n-k}}{x_n}$, n=0, 1, 2, ${\cdots}$. where p, q ${\in}$ (0, ${\infty}$), q ${\neq}$ 2, k ${\in}$ {1, 2, ${\cdots}$} and the initial values $x_{-k}$, ${\cdots}$, $x_0$ are arbitrary positive real numbers.

• 대한수학회지
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• 제47권1호
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• pp.135-163
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• 2010

Motivated by [Science in China (Ser. A Mathematics) 36 (2006), no. 7, 721?732], this article deals with the following discrete type BVP $\LARGE\left\{{{\;{\Delta}[{\phi}({\Delta}x(n))]\;+\;f(n,\;x(n\;+\;1),{\Delta}x(n),{\Delta}x(n + 1))\;=\;0,\;n\;{\in}\;[0,N],}}\\{\;{x(0)-{\sum}^m_{i=1}{\alpha}_ix(n_i) = A,}}\\{\;{x(N+2)-\;{\sum}^m_{i=1}{\beta}_ix(n_i)\;=\;B.}}\right.$ The sufficient conditions to guarantee the existence of at least three positive solutions of the above multi-point boundary value problem are established by using a new fixed point theorem obtained in [5]. An example is presented to illustrate the main result. It is the purpose of this paper to show that the approach to get positive solutions of BVPs by using multifixed-point theorems can be extended to treat nonhomogeneous BVPs. The emphasis is put on the nonlinear term f involved with the first order delta operator ${\Delta}$x(n).

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3692-3695
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• 2011

Poly(N,N'-Dichloro-N-ethyl-benzene-1,3-disulfonamide) (PCBS) and N,N,N',N'-Tetrachlorobenzene-1,3-disulfonamide (TCBDA) were found to be a mild and efficient reagent for the direct oxidative conversion of sulfur compounds to the corresponding arenesulfonyl chlorides in good to excellent yields through the oxidative chlorination. The overall process is simple, practical, and it provides convenient access to a variety of aryl or heteroarylsulfonyl chlorides. The mild reaction conditions and the broad substrate scope render this method attractive, and complementary to existing syntheses of aryl or heteroarylsulfonyl chlorides.

• 대한수학회보
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• 제60권4호
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• pp.863-872
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• 2023

Let n ⩾ 2 be an integer, we denote the smallest integer b such that gcd {(ⁿ_k) : b < k < n - b} > 1 as b(n). For any prime p, we denote the highest exponent α such that p^α | n as v_p(n). In this paper, we partially answer a question asked by Hong in 2016. For a composite number n and a prime number p with p | n, let n = a_mp^m + r, 0 ⩽ r < p^m, 0 < a_m < p. Then we have $$v_p\(\text{gcd}\{\(n\\k\)\;:\;b(n)1\}\)=\{\array{1,&&a_m=1\text{ and }r=b(n),\\0,&&\text{otherwise.}}$$