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Broussochalcone A (BCA) is a chalcone compound extracted from the cortex of Broussonetiapapyrifera (L.) Ventenat that exerts various effects, such as potent antioxidant, antiplatelet, and anticancer effects. However, the effects of BCA against cancers have been seldom studied. This study is aimed at demonstrating the apoptotic mechanisms of BCA in A498 and ACHN cells, which are two types of human renal cancer cell lines. MTT, cell counting, and colony formation assays indicated that BCA treatment inhibited cell viability and cell growth. Further, cell cycle analysis revealed that BCA induced cell cycle arrest at the G2/M phase. Annexin V/PI staining and TUNEL assays were performed to determine the apoptotic effects and DNA fragmentation after treatment with BCA. Based on western blot analysis, BCA induced the upregulation of cleaved PARP, FOXO3, Bax, p21, p27, p53, phosphorylated p53 (ser15, ser20, and ser46), and active forms of caspase-3, caspase-7, and caspase-9 proteins, but downregulated the proforms of the proteins. The expression levels of pAkt, Bcl-2, and Bcl-xL were also found to be downregulated. Western blot analysis of nuclear fractionation results revealed that BCA induced the nuclear translocation of FOXO3, which might be induced by DNA damage owing to the accumulation of reactive oxygen species (ROS). Elevated intracellular ROS levels were also found following BCA treatment. Furthermore, DNA damage was detected after BCA treatment using a comet assay. The purpose of this study was to elucidate the apoptotic effects of BCA against renal cancer A498 and ACHN cells. Collectively, our study findings revealed that the apoptotic effects of BCA against human renal cancer cells occur via the elevation of ROS level and activation of the FOXO3 signaling pathway.

MG132 is a potent, reversible, and cell-permeable 20S proteasome inhibitor and it is derived from a Chinese medicinal plant. The purpose of this study is to investigate the anticancer effects of MG132 against human osteosarcoma U2OS cells. We first performed MTT and colony formation assays to investigate the anti-proliferative effects of MG132. The results demonstrated that MG132 suppressed the proliferation of U2OS cells. Furthermore, we found that treatment with MG132 increased apoptosis and induced DNA damage in U2OS cells. Additionally, zymography, wound healing, and invasion assays showed that MG132 suppressed the enzymatic activity of matrix metalloproteinases, cell migration, and invasion, respectively of U2OS cells. Furthermore, western blotting assay was performed to investigate the apoptotic signaling pathways in MG132-treated U2OS cells. Our results showed that MG132 downregulated the expression of antiapoptotic proteins, including CDK2, CDK4, Bcl-xL, and Bcl-2, whereas it upregulated the expression of proapoptotic proteins, including p21, p27, p53, p-p53 (ser15, ser20, and ser46), cleaved forms of caspase-3, caspase-7, caspase-9, and PARP, and FOXO3 in U2OS cells. These results demonstrated that MG132 activated apoptotic signaling pathways in U2OS cells. Interestingly, MG132 downregulated the phosphorylation of Akt and Erk. Taken together, our results suggest that MG132 has anticancer effects in U2OS cells. Therefore, MG132 may be a potential therapeutic agent for the treatment of osteosarcoma.

Acetylshikonin a natural compound isolated from the root of Lithospermum erythrorhizon and one of the shikonin derivatives which possess promising anticarcinogenic ability. In this study, we attempted to investigate the anti-cancer potential of acetylshikonin towards osteosarcoma U2OS cells. The effects of acetylshikonin towards the treatment of U2OS cells showed that decreased cell proliferation and inhibited migration ability of cells which are experimentally assessed via wide range of assays including MTT, WST-1, cell counting, colony formation assays, wound healing assay and gelatin zymography assay. We also observed that early apoptosis and late apoptosis were increased through fluorescence-activated cell sorter (FACS) analysis. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) assay showed that acetylshikonin induced DNA fragmentation. Western blot analysis revealed the apoptotic effect of acetylshikonin by measuring of proteins such as cleaved caspase -9, -8, -3, -6, -7, and Bcl-2 family. We observed that ROS level and DNA damage were increased via DCF-DA assay and comet assay. In terms of the presence of ROS, induction of apoptosis was detected by measuring proteins such as cleaved caspase 3, PARP, Bcl-2 and Bax. We suggested that the reactions were related to the nuclear translocation of FOXO3 through western blot of cytoplasmic/nuclear protein fractionation. We finally demonstrated that the knockdown of the FOXO3 induced the decrease of the apoptosis-associated proteins via western blot of FOXO3 siRNA transfection. Taken together, these results suggested that acetylshikonin might induce ROS-mediated apoptosis in a FOXO3-dependent manner against osteosarcoma cells. Therefore, acetylshikonin may be elucidated as an effective candidate for the treatment of osteosarcoma.

6,8-Diprenylorobol is a natural compound mainly found in Glycyrrhiza uralensis fisch and Maclura tricuspidata, which has been used traditionally as food and medicine in Asia. So far, the antiproliferative effect of 6,8-diprenylorobol has not been studied yet in colon cancer. In this study, we aimed to evaluate the antiproliferative effects of 6,8-diprenylorobol in LoVo and HCT15, two kinds of human colon cancer cells. 6,8-Diprenylorobol inhibited the proliferation of LoVo and HCT15 cells in a dose- and time-dependent manner. A 40 μM of 6,8-diprenylorobol for 72 h reduced both of cell viability under 50%. After treatment of 6,8-diprenylorobol (40 and 60 μM) for 72 h, late apoptotic cell portion in LoVo and HCT15 cells were 24, 70% and 13, 90%, respectively, which was confirmed by checking DNA fragmentation in both cells. Mechanistically, 6,8-diprenylorobol activated p53 and its phosphorylated form (Ser15, Ser20, and Ser46) expression but suppressed Akt and mitogen-activated protein kinases (MAPKs) phosphorylation in LoVo and HCT15 cells. Interestingly, 6,8-diprenylorobol induced the generation of intracellular reactive oxygen species (ROS), which was attenuated with N-acetyl cysteine (NAC) treatment. Compared to the control, 60 μM of 6,8-diprenylorobol caused to increase ROS level to 210% in LoVo and HCT15, which was reduced into 161% and 124%, respectively with NAC. Furthermore, cell viability and apoptotic cell portion by 6,8-diprenylorobol was recovered by incubation with NAC. Taken together, these results indicate that 6,8-diprenylorobol has the potential antiproliferative effect against LoVo and HCT15 colon cancer cells through activation of p53 and generation of ROS.

The surface migration of lubricants degrades the quality of thermoplastic polymer composites. In this study, the surface migration of lubricants in polypropylene composites were studied to improve the quality of the composites. Polypropylene (PP)/lubricant composites were manufactured using a co-rotating twin-screw extruder and injection molding, and the migration phenomena of the lubricant in the PP/lubricant composites were investigated under accelerated aging conditions with temperatures in the range of 20 to 90 °C and humidity of 100% for 72 h. The interrelation between the surface migration properties of PP/lubricant composites were investigated by considering their microstructural and morphological features, which were influenced by the thermal aging conditions. Further, the microstructural and morphological features were examined by contact angle, surface energy, attenuated total reflectance Fourier-transform infrared spectrometry, X-ray photoelectron spectroscopy, close-up digital imaging, and atomic force microscopy analyses. The polypropylene composites containing the magnesium stearate as the lubricant were found to exhibit a more stable migration behavior than the polypropylene composites containing a calcium stearate lubricant. This is attributed to multiple synergistic factors, such as interfacial tension and work of adhesion between PP and the lubricant. The findings of this study can be utilized to effectively manufacture high-quality thermoplastic composites for the fourth industrial revolution.

The purpose of this study was to investigate the effects of core strengthening training on baseball throwing. A total of 14 subjects were recruited from among middle school baseball players. The main outcome measures were as follows: speed guns were used to measure the velocity of baseballs thrown; scored targets were used to measure throwing accuracy; and 50m measuring tapes were used to measure throwing distances. It was found that core strengthening training improved the velocity of baseballs thrown and throwing accuracy and distance. Thus, core strengthening training is effective for improving the throwing ability of baseball players.

This study aimed to examine the most effective exercise method for shoulder joint rehabilitation by comparatively observing activity of shoulder stabilizer muscles during push up and push up plus exercises under diverse stable conditions. The subjects were 20 healthy adults students who went to M university. While the subjects conducted push up and push up plus exercises under diverse stable conditions(a stable surface, a support of 25cm height, a support of 30 cm height and a balance pad), activities of the upper trapezius muscle, pectoralis major muscle, serratus anterior muscle, and triceps brachii muscle were recorded. During push up and push up plus exercises, activities of the stabilizer muscles were higher when the stable condition was changed rather than on the stable surface. In particular, when the support of 30cm height and balance pads were applied, activity of the shoulder stabilizer was highest. There were significant differences in the upper trapezius muscle and triceps brachii muscle during the push up exercise(p

본 연구에서는 PC/ABS 블렌드를 고속전단성형법을 사용하여 제조하였고 스크류 회전속도와 전단부하시간을 공정변수로 하여 이에 따른 블렌드의 모폴로지 변화를 분석하였다. 블렌드의 모폴로지 및 ABS 분산상의 크기를 주사전자현미경으로 관찰하여 안정한 상 구조와 최적의 물성을 가지는 고속전단성형조건을 확립하였고, 전단응력에 의한 블렌드의 열화 현상을 알아보기 위해 기계적 물성의 변화를 측정하였다. 이 때, 스크류 회전속도는 500 rpm에서 3000 rpm까지 변화시켰으며 전단부하시간은 10초에서 40초까지 주었다. 고속전단성형법을 사용하여 제조한 PC/ABS 블렌드 및고속전단성형을 가하지 않은PC/ABS 컴파운드의 분산상 크기를 명확하게 관찰하기 위하여 블렌드의 단면에 크롬산 수용액을 이용한 에칭공정을 시행하였고 공정 전후의 모폴로지를 비교 분석하였다. 에칭으로 생긴 블렌드 내의 ABS 홀을 이미지 측정 프로그램인 Image J를 이용하여 측정한 결과, 스크류 회전속도에 따라 그 크기가 감소하였으며 특히1000 rpm 이상의 스크류 회전속도 하에서 제조된 PC/ABS 블렌드의 경우, 기계적 물성이 급격하게 감소하여 블렌드의분해가 일어났음을 알 수 있었다. 결과적으로 PC/ABS 블렌드에 1000 rpm의 스크류 회전속도를 가한 경우, 나노미터단위의 분산상을 가지며 가장 안정한 상구조를 관찰할 수 있었고 인장강도 및 신율도 상대적으로 높아서 PC/ABS 블렌드의 최적 고속전단성형조건이라 할 수 있다.

PURPOSE: The purpose of this study was to investigate the effect of sensorimotor training in unstable surface on balance ability of elderly women. METHODS: Total of 40 subject were recruited from two separated institution for elderly women in Changwon and conveniently allocated into experimental and control groups. Twenty women were included into experimental group and another twenty women were into control group. Experimental group performed sensorimotor training in unstable surface and control group were only activities of daily living during eight weeks. To assess static balance ability used One leg stance test (OLST) and to assess dynamic balance ability used timed up and go test (TUGT) and Functional reach test (FRT). RESULTS: Control group did not show any difference in balance ability. However static balance ability in experimental group improved on hard or soft surface only eye open condition. Also dynamic balance ability in experimental group improved TUGT or FRT. CONCLUSION: Sensorimotor training in unstable surface improved balance ability of elderly women.

The effects of high shear rate processing on the thermal properties of PC/ABS blends were studied. It was executed by the high shear processing machine (NHSS2-28) at the varied conditions of screw speeds and loaded duration. After the samples were processed with NHSS2-28, the Tgs were shifted from 143 to 133 C, and the behavior of degradation determined by TGA showed two distinct steps before high shear rate processing, while it showed a straight line after the processing. In order to provide the reasons of the properties, it was showen by SEM and UTM that the droplet sizes morphologically decreased after the processing, and the elongations decreased slightly until 1000 rpm of screw speed and then sharply decreased, according to the conditions of high shear rate processing. Therefore, it can be confirmed that Tg,s of PC/ABS blends were considerably shifted under an appropriate high shear rate condition, and rapidly dropped, so that blends degraded above the condition, due to stress-induced degradation.

Polycarbonate/Acrylonitrile-Butadiene-Styrene(PC/ABS) 블렌드의 분해효과를 조사하기 위해 고전단 압출 성형기의스크류 회전속도와 전단시간의 함수로 PC/ABS의 물성변화에 영향을 미치는 산화방지제의 효과를 연구하였다. 인산계산화방지제로 Tris-(2,4-di-tert-butyl-phenyl phosphate) (이후 A1로 명명) and Bis(2,4-dicumylphenyl) pentaerythritoldiphosphite(이후 A3로 명명)가 사용되었고, 페놀계 산화방지제는 Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate(이후 A2로 명명)가 사용되었다. 열적 물성은 TGA를 통해 측정되었고 고속 전단 가공 후 크게 감소하였다. 산화방지제 A3가 포함된 PC/ABS 블렌드는 다른 산화방지제에 비해 스트레스로 유발된 degradation과, 열적 degradation이지연되었다. 고속 전단 가공 후 UTM을 사용한 기계적 물성 또한 산화방지제 종류에 따라 각각 감소하였고, 특히, 신율의 경우 크게 감소하는 거동이 나타난 것에 비해 인장강도의 변화는 매우 적었다. 스크류 회전속도 1000 rpm, 전단부하 시간 20초 조건에서의 신율로 예를 들면, 고속 전단 가공하기 전 신율인 148%에서 A1은 91.6%, A2는 63%, A3은 131%로 감소하였다. 형태학적 물성을 알기 위해 SEM을 사용하여 PC/ABS의 분산상을 조사하였고, 스크류 회전속도와 하중이 작용한 기간이 증가함에 따라 그 크기 분포가 감소하였다. 따라서, 세 종류 산화방지제 모두 고속 전단 가공에서 스트레스로 유발되는 PC/ABS 블렌드의 degradation을 억제하고, 그 효과는 A3가 가장 뛰어난 것을 확인하였다.

PURPOSE: The purpose of this research was comparing and analyzing the exercise effect for the public who was not suffering back pain exercise in improving the waist flexibility, the waist muscular strength and the waist sense of equilibrium after grafted in William & McKenzie exercise with swiss ball. METHODS: 16 people who were not in progress of the chronic low-back pain were recruited. They were grouped into 8 for each experiment(GSBE

In this study, the effects of repeated extrusion on the mechanical properties, morphology, and interfacial tension of polypropylene (PP)/ethylene propylene diene monomer (EPDM) (80/20) blends were investigated. For the PP/EPDM (80/20) blends, the impact strength of the blends increased with repeated extrusion, which could be attributed to the interaction between the PP and the EPDM. The interfacial tension of the PP/EPDM (80/20) blends, which was determined using the Palierne and Choi–Schowalter models, decreased with an increase in the number of repeated extrusion. Based on the results of the mechanical properties and morphology, the interaction between the PP and the EPDM with repeated extrusion contributed to the reduction of interfacial tension between the PP and the EPDM, which consequently improved the impact strength of the PP/EPDM (80/20) blends. The results for the nuclear magnetic resonance studies supported the increase in impact strength of the PP/EPDM (80/20) blends with repeated extrusion. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Application of the Object-oriented Programming (OOP) method to the Finite Element Model (FEM) program has various strengths including the features of encapsulation, polymorphism and inheritance. However, this technique should be based upon a premise that the independency of the object method and data to be used is guaranteed. By attempting to apply the OOP to the FEM, existing researches go against the independency of the OOP which is an essential feature of the method. The reason is this: existing researches apply the OOP to modules in accordance with analysis procedures, although the data to be used is classified as an element unit in the FEM. Therefore, the required independency cannot be maintained as whole stiffness matrices and boundary conditions are combined together. Also, solutions are sought from analysis module after data is regrouped at the pre-processor, and their results are analyzed during the post-processor. As this is similar to a batch processing, it cannot use data at analysis, and recalculation should be done from the beginning if any condition is changed after the analysis is complete, which are limitations of the existing researches. This research implemented the Object-orientation of elements so that the three features of the OOP (i.e. encapsulation, polymorphism and inheritance) can be guaranteed and their independency maintained as a result. For this purpose, a model called `Object-oriented Finite element Model ensuring the Independency of Elements (OFMIE)`, which enables the analysis of targets through mutual data exchanges within instance, was developed. In conclusion, the required independency was achieved in the instance of the objected elements and the analysis results of previous conditions could be used for the analysis after changes. The number of repetitive calculations was reduced by 75 per cent through this gradual analysis processes.

The purpose of this study was to investigate the improvement of allergic dermatitis in chemical allergen-induced mice by Lactobacillus sakei probio 65. L. sakei probio-65 was isolated from kimchi, a traditional Korean fermented food. This strain was resistant to gastric acidity, bile, and several antibiotics and possessed antimicrobial activity against several pathogenic microorganisms. To investigate whether the probiotic activity of L. sakei probio 65 was effective for treating allergic dermatitis, the organism was supplied to mice triggered by allergen (1-chloro-2,4-dinitrobenzene). Mice that received L. sakei probio 65 showed a more rapid recovery compared to control mice, as assessed by visual evaluation of the severity of allergic dermatitis and levels of immunoglobulin (Ig) E and interleukin (IL)-4. L. sakei probio 65 exhibited good probiotic properties in vitro and in mice and was effective in reducing allergen-induced skin inflammation through the regulation of both elevated IgE and IL-4 in sensitized mice.

Polyketone fiber is considered as a reinforcement of the mechanical rubber goods (MRG) such as tires, automobile hoses, and belts because of its high strength and modulus. In order to apply it to those purposes, the high adhesion of fiber/rubber interface and good sustainability to aging conditions are very important. In this study, polyketone fiber reinforced natural rubber composites were prepared and they were subjected to thermal and humidity aging, to assess the changes of the interfacial adhesion and material properties. Also, the effect of adhesive primer treatment, based on the resorcinol formaldehyde resin and latex (RFL), of polyketone fiber for high interfacial adhesion was evaluated. Morphological and property changes of the rubber composites were analyzed by using various instrumental analyses. As a result, the rubber composite was aged largely by thermal aging at high temperature rather than humidity aging condition. Interfacial adhesion of the polyketone/NR composites was improved by the primer treatment and its effect was maintained in aging conditions.

A wide range of enzymes have been utilized as the catalysts in organic synthesis. Among them, hydrolytic enzymes such as lipases and esterases have been most frequently employed as a result of their broad substrate specificity and good enantioselectivity. These enzymes have been particularly useful in the synthesis of opti-cally active alcohols, acids, and esters.

Dynamic kinetic resolution (DKR) provides a useful methodology for the conversion of racemic substrates to single enantiomeric products. In the last decade, a new approach for DKR has been intensively explored, in which an enzyme as the resolution catalyst is combined with a metal or metal complex as the racemization catalyst. Several enzyme-metal combinations have been developed for the DKR of alcohols. Among them, lipase-ruthenium combinations are particularly useful for the (R)-selective DKR of secondary alcohols. A wide range of simple and functionalized secondary alcohols have been transformed to enantiomerically-enriched forms with them. In many cases, high yields and enantiomeric excesses approaching 100% were realized. The (S)-selective DKR of secondary alcohols, however, has been much less intensively explored compared to its counterpart. We reported for the first time the use of a subtilisin-ruthenium combination for such DKR, which was applied to a limited number of simple secondary alcohols. As our continuous efforts in this area, we now wish to report an application of subtilisin-ruthenium combination in the DKR of functionalized alcohols such as allylic alcohols. Chiral allylic alcohols in optically pure forms are synthetically important synthons which can be transformed to a wide range of more complex molecules. Previously we reported a procedure based on a lipase-ruthenium combination for the (R)-selective DKR of allylic alcohols. Accordingly, we became interested in developing a complementary procedure for the synthesis of opposite enantiomers, which would be realized by using subtilisin as the resolution catalyst in the presence of a ruthenium-based racemization catalyst (Scheme 1). For the (S)-selective DKRs of allylic alcohols, 10 different compounds 2a-j were examined as substrates with a commercial enzyme (subtilisin CLEC) and a ruthenium complex 1 as the catalysts (Scheme 2). In a typical procedure, the reaction was performed for 3 days at room temperature with a mixture of substrate (0.3 mmol), subtilisin CLEC (15 mg/mmol of substrate), 1 (4 mol%, preactivated with potassium t-butoxide), and trifluoroethyl butyrate (5.1 mmol) as an acyl donor in THF. The acylated products were isolated by silica gel chromatography and their optical purities were analyzed by chiral HPLC. The data from Table 1 indicate that satisfactory resolution has been accomplished in all the cases. The isolated yields ranged from 73 to 92% and the enantiomeric excesses reached 96% or greater. It was observed that the yields were lowered by side reactions such as oxidation and isomerization, leading to the formation of ketones such as 4 and 5 (Scheme 3). The yields of byproducts ranged from 5 to 9%. The S-configuration of the acylated products was confirmed by comparing the optical rotation (−23.1 for c = 1, CHCl3, >99% ee) of allylic alcohol (S)-2d obtained from the hydrolytic deacylation of 3d with the literature value (−25.4 for c = 1, CHCl3, >99% ee). 7

National Research Laboratory of Chirotechnology, Department of Chemistry, Division of Molecular and Life Sciences,Pohang University of Science and Technology, Kyungbuk 790-784, KoreaReceived March 11, 2004An efficient dynamic kinetic resolution of racemic β-hydroxyalkylferrocene and 1,1'-bis(β-hydroxyalkyl)-ferrocene derivatives was achieved using lipase/ruthenium-catalyzed transesterification in the presence of anacyl donor. The racemic β-hydroxyalkylferrocene derivatives were successfully transformed to thecorresponding chiral acetates of high optical purities in high yields.Key Words : Dynamic kinetic resolution (DKR), Enzyme/metal bicatalysis, Lipase, β-HydroxyalkylferroceneIntroductionThe chiral ferrocene derivatives have been widely used aschiral ligands in asymmetric synthesis

Dynamic kinetic resolution (DKR) provides a useful methodology for the conversion of racemic substrates to single enantiomeric products. In the last decade, a new approach for DKR has been intensively explored, in which an enzyme as the resolution catalyst is combined with a metal or metal complex as the racemization catalyst. Several enzyme-metal combinations have been developed for the DKR of alcohols. Among them, lipase-ruthenium combinations are particularly useful for the (R)-selective DKR of secondary alcohols. A wide range of simple and functionalized secondary alcohols have been transformed to enantiomerically-enriched forms with them. In many cases, high yields and enantiomeric excesses approaching 100% were realized. The (S)-selective DKR of secondary alcohols, however, has been much less intensively explored compared to its counterpart. We reported for the first time the use of a subtilisin-ruthenium combination for such DKR, which was applied to a limited number of simple secondary alcohols. As our continuous efforts in this area, we now wish to report an application of subtilisin-ruthenium combination in the DKR of functionalized alcohols such as allylic alcohols. Chiral allylic alcohols in optically pure forms are synthetically important synthons which can be transformed to a wide range of more complex molecules. Previously we reported a procedure based on a lipase-ruthenium combination for the (R)-selective DKR of allylic alcohols. Accordingly, we became interested in developing a complementary procedure for the synthesis of opposite enantiomers, which would be realized by using subtilisin as the resolution catalyst in the presence of a ruthenium-based racemization catalyst (Scheme 1). For the (S)-selective DKRs of allylic alcohols, 10 different compounds 2a-j were examined as substrates with a commercial enzyme (subtilisin CLEC) and a ruthenium complex 1 as the catalysts (Scheme 2). In a typical procedure, the reaction was performed for 3 days at room temperature with a mixture of substrate (0.3 mmol), subtilisin CLEC (15 mg/mmol of substrate), 1 (4 mol%, preactivated with potassium t-butoxide), and trifluoroethyl butyrate (5.1 mmol) as an acyl donor in THF. The acylated products were isolated by silica gel chromatography and their optical purities were analyzed by chiral HPLC. The data from Table 1 indicate that satisfactory resolution has been accomplished in all the cases. The isolated yields ranged from 73 to 92% and the enantiomeric excesses reached 96% or greater. It was observed that the yields were lowered by side reactions such as oxidation and isomerization, leading to the formation of ketones such as 4 and 5 (Scheme 3). The yields of byproducts ranged from 5 to 9%. The S-configuration of the acylated products was confirmed by comparing the optical rotation (−23.1 for c = 1, CHCl3, >99% ee) of allylic alcohol (S)-2d obtained from the hydrolytic deacylation of 3d with the literature value (−25.4 for c = 1, CHCl3, >99% ee). 7

National Research Laboratory of Chirotechnology, Department of Chemistry, Division of Molecular and Life Sciences,Pohang University of Science and Technology, Kyungbuk 790-784, KoreaReceived March 11, 2004An efficient dynamic kinetic resolution of racemic β-hydroxyalkylferrocene and 1,1'-bis(β-hydroxyalkyl)-ferrocene derivatives was achieved using lipase/ruthenium-catalyzed transesterification in the presence of anacyl donor. The racemic β-hydroxyalkylferrocene derivatives were successfully transformed to thecorresponding chiral acetates of high optical purities in high yields.Key Words : Dynamic kinetic resolution (DKR), Enzyme/metal bicatalysis, Lipase, β-HydroxyalkylferroceneIntroductionThe chiral ferrocene derivatives have been widely used aschiral ligands in asymmetric synthesis

A soluble Cr(VI) reductase was purified from the cytoplasm of Escherichia coli ATCC 33456. The molecular mass was estimated to be 84 and 42 kDa by gel filtration and SDS-polyacrylamide gel electrophoresis, respectively, indicating a dimeric structure. The pI was 4.66, and optimal enzyme activity was obtained at pH 6.5 and 37 degrees C. The most stable condition existed at pH 7.0. The purified enzyme used both NADPH and NADH as electron donors for Cr(VI) reduction, while NADPH was the better, conferring 61%; higher activity than NADH. The Km values for NADPH and NADH were determined to be 47.5 and 17.2 micromol, and the Vmax values 322.2 and 130.7 micromol Cr(VI) min(-1)mg(-1) protein, respectively. The activity was strongly inhibited by N-ethylmalemide, Ag2+, Cd2+, Hg2+, and Zn2+. The antibody against the enzyme showed no immunological cross reaction with those of other Cr(VI) reducing strains.

In this paper, we propose a blind watermarking scheme using the properties of wavelet coefficient sign. We found it through some experiments that the wavelet coefficient sign is robust against lossy compression methods such as JPEG and JPEG-2000. So we tried to change the characteristic along sub-blocks which decided in advance for watermark insertion. Also, because the proposed algorithm uses the Daubechies 9-tap/7-tap wavelet filter bank, it can be applied to JPEG-2000 lossy compression process directly. Various attacks were given to demonstrate the robustness of the proposed technique.

E-commerce is being gradually replaced by M-commerce due to the popularization of the Internet and mobile phones. An e-payment system for M-commerce applies existing wired system as it is. There are security and inefficiency problems. The limited resources of equipment require the e-payment protocol in the wireless Internet environment to be designed in consideration of efficiency in the computing function and the storage device. The paper suggests an e-payment system for M-commerce that minimizes public key computing and guarantees anonymity concerning personal and purchasing information as well as storage spatial efficiency. The suggested system realizes an e-payment system, using independent J2ME (Java 2 Micro Edition) based CLDC (connect limited device configuration) and MIDP (mobile information device profile) in the platform in order to support diversified applicational services for M-commerce.

A new procedure for the dynamic kinetic resolution (DKR) of racemic alcohols into single enantiomers is described. This procedure employs surfactant-treated subtilisin as an (S)-selective resolving catalyst and an aminocyclopentadienylruthenium complex as a racemizing catalyst. The DKR is performed best in the presence of an acyl donor such as trifluoroethyl butyrate in THF at room temperature. Eight simple secondary alcohols have been efficiently resolved with high optical purities and good yields. The subtilisin-based DKR is complementary in stereoselectivity to its lipase-based counterpart. For an acyl-carrying alcohol, both subtilisin- and lipase-based DKRs have proceeded equally well to give a pair of enantiomeric products (>99.5% ee each) with opposite optical rotations in high yields (94−95%).