• Bulletin of the Korean Mathematical Society
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• v.42 no.1
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• pp.169-177
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• 2005

A Hilbert Space operator T is of class Q if $T^2{\ast}T^2-2T{\ast}T + I$ is nonnegative. Every paranormal operator is of class Q, but class-Q operators are not necessarily normaloid. It is shown that if a class-Q contraction T has no nontrivial invariant subspace, then it is a proper contraction. Moreover, the nonnegative operator Q = $T^2{\ast}T^2-2T{\ast}T + I$ also is a proper contraction.

• Journal of Food Hygiene and Safety
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• v.9 no.2
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• pp.75-80
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• 1994

The effects of ursodeoxycholic acid (UDCA) were studied on the hepatotoxicity induced by several hepatotoxicants such as carbonte trachloride, thioacetamide and 1-naphthylisothiocyanate in ICR male mice. UDCA (50 mg/kg, 100 mg/kg) decreased the elevated serum bilirubin in carbon tetrachloride intoxicated mice, the elevated serum AST, alkaline phosphatase in thioacetamide intoxicated mice, the elevated serum AST and bilirubin in 1-naphthylisothiocyanate intoxicated mice.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.5
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• pp.347-353
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• 2018

There are some controversies about the safety of herbal medicine. In order to examine the safety of herbal medicine, this study investigated the level of liver function test(AST/ALT) in patients taking herbal medicine for more than 6 months We checked liver function in 121 patients who took herbal medicine for more than 6 months. AST/ALT were measured before treatment and every 3 months (from 3 month to 9 month). In 121 patients taking herbal medicine for more than 6 months, mean AST level after 6 months was lower than before treatment and mean ALT level after 6 months was lower than before treatment. In 20 patients with abnormal AST/ALT before herbal treatment, 18 patients's AST/ALT changed to normal after 6 month herbal treatment. 2 patients's AST/ALT was slightly higher than normal. One woman patient met the criteria for herb-induced liver injury(HILI) with RUCAM scores 4 after taking herbal medicine for 6 months. Although her RUCAM score decreased to zero after taking herbal medicine for 9 months. This study suggests that long-term herbal medicine for 6 months or longer is very unlikely to injury liver function. Individual-specific liver damage may occur, it can be recovered.

• Food Science of Animal Resources
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• v.26 no.3
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• pp.386-393
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• 2006

The effects of Curcuma extract Solomon's seal (Polygonatum odoratum var. pluriflorum), and maltodextrose on acute hepatotoxicity in Sprague-Dawley (SD) rats were investigated. Acute hepatotoxicity was induced by 0.5 mL of carbon tetrachloride ($CCl_4$) per kg of SD rats, which was injected to them before administration of Curcuma extract or both Solomon's seal (Polygonatum odoratum var. pluriflorum) and maltodextrose mixtures. SD rats dose with Curcuma extract of 4 mg or 40 mg per kg per day significantly (p<0.05) reduced the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALKP) after 7 days compared to the controls dose with water. Treatments of Curcuma extract with 4 mg per kg per day in SD rats significantly (p<0.05) reduced aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALKP) to 78.0%, 82.6%, and 76.3% after 7 days compared to the controls, respectively. The levels of AST and ALT in SD rats dose with both Solomon's seal (Polygonatum odoratum var. pluriflorum) and maltodextrose mixtures or either alone had no significantly different (p>0.05) compared to the controls. Treatments of Curcuma extract combined with Solomon's seal (Polygonatum odoratum var. pluriflorum) and maltodextrose mixtures was 'liked more' to the sensory scores for odor and flayer compared to the controls. It was considered that Curcuma extract combined with both Solomon's seal (Polygonatum odoratum var. pluriflorum) and maltodextrose mixtures could be used to functional food for enhancement of health and consumer acceptance.

• Korean Journal of Mathematics
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• v.24 no.4
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• pp.647-662
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• 2016

In this paper, we study Lipschitz continuous, the boundedness and compactness of the composition operator $C_{\phi}$ acting between the general hyperbolic Bloch type-classes ${\mathcal{B}}^{\ast}_{p,{\log},{\alpha}}$ and general hyperbolic Besov-type classes $F^{\ast}_{p,{\log}}(p,q,s)$. Moreover, these classes are shown to be complete metric spaces with respect to the corresponding metrics.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.201-204
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• 2002

The rates of the aminolysis of S-phenyl substituted-acetate series $(RC(=O)SC_6H_4Z$, with R=Me, Et, i-Pr, t-Bu and Bn) with benzylamines $(XC_6H_4CH_2NH_2)$ are not correlated simply with the Taft's polar $({\sigma}^{\ast})$ and/or steric effect constants $(E_s)$ of the substituents due to abnormally enhanced rate of the substrate with R=Et. Furthermore, the cross-interaction constant, ${\rho}x_z$ , is the largest with R=Et. These anomalous behaviors can only be explained by invoking the vicinal bond $({\sigma})$-antibond $({\sigma}^{\ast})$ charge transfer interaction between C-$C{\alpha}$ and C-S bonds. In the tetrahedral zwitterionic intermediate, $T^{\pm}$ , formed with R=Et the vicinal ${\sigma}_{c-c}-{\sigma}^{\ast}_{c-s}$ delocalization is the strongest with an optimum antiperiplanar arrangement and a narrow energy gap, ${\Delta}{\varepsilon}={\varepsilon}_{{\sigma}^{\ast}}-{\varepsilon}_{\sigma}$. Due to this charge transfer interaction, the stability of the intermediate increases (with the concomitant increase in the equilibrium constant K (= $k_a/k_{-a}$)) and also the leaving ability of the thiophenolate leaving group increases (and hence $k_b$ increases) so that the overall rate, $k_n\;=\;Kk_b$, is strongly enhanced. Theoretical support is provided by the natural bond orbital (NBO) analyses at the B3LYP/6-31+$G^{\ast}$ level. The anomaly exhibited by R=Et attests to the stepwise reaction mechanism in which the leaving group departure is rate limiting.

• Journal of applied mathematics & informatics
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• v.4 no.2
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• pp.513-528
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• 1997

A sort sequence $S_n$ is a sequence of all unordered pairs of indices in $I_n\;=\;{1,\;2,v...,\;n}$. With a sort sequence Sn we assicuate a sorting algorithm ($AS_n$) to sort input set $X\;=\;{x_1,\;x_2,\;...,\;x_n}$ as follows. An execution of the algorithm performs pairwise comparisons of elements in the input set X as defined by the sort sequence $S_n$, except that the comparisons whose outcomes can be inferred from the outcomes of the previous comparisons are not performed. Let $X(S_n)$ denote the acverage number of comparisons required by the algorithm $AS_n$ assuming all input orderings are equally likely. Let $X^{\ast}(n)\;and\;X^{\circ}(n)$ denote the minimum and maximum value respectively of $X(S_n)$ over all sort sequences $S_n$. Exact determination of $X^{\ast}(n),\;X^{\circ}(n)$ and associated extremal sort sequenes seems difficult. Here, we obtain bounds on $X^{\ast}(n)\;and\;X^{\circ}(n)$.

• The Journal of Internal Korean Medicine
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• v.21 no.1
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• pp.108-115
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• 2000

Objective : To investigate the hepatoprotective effects of Gami-oryungsan on the liver damage induced by bromobenzene. Method : The development of fibrosis and acute liver injury was examined by the chemical analysis of AST, AL T, ${\gamma}$-GTP . and epoxide hydrolase glutathione S-transferase glutathione peroxidase enzyme activity, lipidoperoxide levels, glutathione levels were measured and oberved. Results : The increasing levels of lipidoperoxide was decreased proportionally according to dose of extract GO. Epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity highly increased in GO pre-acupunctured group compared with the group treated with only bromobenzene. The increase of serum AST, AL T, ${\gamma}$-GTP enzyme activity of mice by bromobenzene was inhibited by the administration of GO. Lipidoperoxide levels in rat's liver decreased compared to the case of bromobenzene-treated group. The levels of Glutathione decreased by bromo benzene were increased highly in GO pre-acupunctured group. Conclusion : These results suggest that GO extract recovers the damage of liver due to bromobenzene intoxication by decreasing the lipid peroxidation AST AL T ${\gamma}$-GTP enzyme activity and increasing epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity, glutathione levels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.896-901
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• 2007

This study was carried out to investigate the effect of the addition of olive and soybean oil on the color, water holding capacity, cooking loss, increase rate of thickness, decrease rate of diameter, pH, VBN content and TBARS value of ground pork loin during cold storage for 15 days. Ground pork loin were prepared by three types such as ground pork loin containing 20% pork fat (GP-P), ground pork loin containing 20% olive oil (GP-O) and ground pork loin containing 20% soybean oil (GP-S). The $L^{\ast}$ (lightness) and $b^{\ast}$ (yellowness) value of GP-P, GP-O and GP-S were not significantly different during storage, and the $L^{\ast}$, $a^{\ast}$ and $b^{\ast}$ value of GP-P were higher than those of GP-O and GP-S (p<0.05). The water holding capacity tended to increase along with storage period, the water holding capacity of GP-P was higher than that of GP-O and GP-S. Also, the cooking loss of GP-P was lower than that of GP-O and GP-S (p<0.05). The increase rate of thickeness by cooking increased along with storage period, but the decrease rate of diameter was tend to decreased with increase in storage period (p<0.05). The pH of all ground pork loins decreased until storage at 5 days, but increased at 15 days (p<0.05). The VBN content of all ground pork loins increased along with storage period, and the VBN content of GP-P was higher than that of GP-O and GP-S (p<0.05). The TBARS value of all ground pork loins increased along with storage period; also, the VBN content of GP-P was the highest among all ground pork loins and GP-O was the lowest among all ground pork loins (p<0.05).

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.16-20
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• 2021

Since the durability evaluation for improving the durability of PEMFC polymer membranes is very important for the development of PEMFC, research and development of the polymer membrane durability evaluation protocol (AST) continues. Recently, DOE's polymer membrane chemical/mechanical durability evaluation AST was developed and applied to Nafion XL for review. In order to shorten the evaluation time, oxygen was used as a cathode gas instead of air, and it was finished in 144 hours. Since DOE AST has a large number of voltage changes with 45 seconds of humidification and 30 seconds of drying, the degradation of the electrode has more influence on the MEA durability. Therefore, one cycle time was lengthened with 60sec of wet/300sec of dry, and the drying time was made longer than the humidification time to further deteriorate the polymer membrane, and it was finished in 240 hours. It was confirmed that the DOE AST for evaluation of the durability of the polymer membrane was accompanied by electrode degradation.