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We empirically investigate how uncertainty endogenously interacts with real activity and monetary policy, and analyze the role of endogeneity in shaping the efficacy of monetary policy using a shock restricted structural vector-auto-regression model. Using the model, we show that both real and financial uncertainty endogenously react to business cycle fluctuations and to monetary policy actions. Then we provide two novel policy implications of endogenous uncertainty. First, a tighter monetary policy reduces financial uncertainty, but heightens real uncertainty. Second, endogeneity channels in uncertainty amplify the real effects of monetary policy.

Dieckol is a brown algae-derived polyphenol that has broad bioactivity and low toxicity. Therefore, it is a promising lead compound for the development of therapeutic agents to treat various pathological conditions, including viral infections, allergies, diabetes, skin ageing, cancers, and neurodegenerative conditions. To exploit the pharmacological potential of dieckol, its stability, solubility, pharmacokinetics, and drug delivery must be improved. This can be achieved by the controlled modification of the hydroxyl groups, but the presence of eleven nearly equivalent hydroxyl groups makes the task highly challenging. In this study, the regioselectivities in five substitution reactions of the hydroxyl groups of dieckol under various SN2 reaction conditions were investigated. After reaction optimization, five substituents (methyl, benzyl, methoxymethyl, 3-hydroxypropyl, and 3-(ethoxycarbonyl)propyl) could be introduced at the 6-Oposition of dieckol with surprisingly high regioselectivity, as confirmed by 2D-NMR spectroscopic analyses. The prepared dieckol derivatives showed antioxidant and anticancer activities analogous to those of unmodified dieckol, indicating that the mono-O-substitutions did not affect the biochemical and biological characteristics of dieckol. Therefore, the proposed methodology for the mono-O-substitution of a specific oxygen of dieckol is a powerful tool to add various pharmaceutical attributes to dieckol, thus contributing to the development of various dieckol-based drug candidates.

A novel tetrakis(4-(5,5-dimethyl-2-phenyl-1,3-dioxan-2- yl)phenyl)germane (2) was synthesized by the reaction of germanium(IV) tetrachloride with 4-(5,5-dimethyl-2-phenyl-1,3-dioxan-2-yl)phenyllithium. Colorless plate-shaped single crystals obtained from recrystallization in ether were characterized by the single-crystal X-ray diffraction. The organogermanium compound was crystallized in a noncentrosymmetric nonpolar tetragonal space group, I-4, and classified as a porous molecular material owing to the presence of two types of distinct channels as a result of intermolecular hydrogen bonding. Compound 2 exhibits a differential gas adsorption property. The powder second-harmonic generating (SHG) measurements indicate that compound 2 shows a SHG efficiency 10 times greater than those of α-SiO2 and type-1 nonphase-matchable.

In this study, the effect of alkyl chain length in amine-based compounds on the work function of graphene was investigated. The graphene was synthesized by the chemical vapor deposition method. The graphene layers were functionalized by amine-based groups using a simple spin-coating method. The amine-based compounds were composed of phenyl amine and methyl-, ethyl-, propyl-, n/t-butyl-, and octyl-phenyl amine groups. Materials were confirmed by X-ray photoelectron spectroscopy to show the C and N bonding. The work function of the doped graphene layers decreased because of the effect of the doping agents. Among the doped graphene samples, t-butyl-phenyl amine functionalized graphene achieved the lowest work function of 3.89 eV (compared with 4.43 eV for pristine graphene). Further, the sheet resistance of n-doped graphene increased, confirming the high concentration of n-doping agents on the graphene layers. These results suggest the best alkyl chain is the t-butyl group to reduce the work function of graphene, and promise the use of these materials as cathodes for opto-electronic applications.

This study investigates whether the Federal Reserve (Fed) should care about inequality. We develop a Heterogeneous Agent New Keynesian (HANK) model, which generates empirically realistic inequalities and business cycle properties observed in the U.S. data. Households in the model economy are subject to the aggregate productivity shock and to the idiosyncratic labor efficiency and preference shocks. In addition, the model distinguishes the extensive and intensive margins of labor supply. We consider the income Gini coefficient in a monetary policy rule to see how an inequality-targeting monetary policy might affect aggregate and disaggregate outcomes, as well as economic welfare. First, we find that a monetary policy rule with an explicit inequality target can be welfare improving, even if inequality becomes volatile. Second, there is an efficiency-equity trade-off: an economy should sacrifice a more volatile output in order to have smaller cyclical variations in its inequality measures. Lastly, when the Fed targets the employment of a specific group of households, it can improve economic welfare and stabilize inequality at the same time.

English Abstract: Long-term interest rates show considerable reactions to macroeconomic and monetary policy news. It is, however, difficult to be explained by standard rational expectations macro-finance models widely used in policy analyses. In this research, we demonstrate that private’s subjective beliefs and central bank credibility can account for the excess sensitivity of long-term interest rates using an estimated macro-finance model which incorporates private’s subjective perceptions on future real activity and inflation and endogenously evolving central bank credibility. We find that long-term rates respond stronger to macro shocks and shifts in private's perceptions regarding expected real activity and inflation when credibility is lower. In addition, the model simulation shows that 10-year yield varies substantially more when credibility is low.

Chalcone derivatives have been investigated as therapeutic agents for the anticancer, antioxidant, and anti-inflammatory fields. In this study, we have synthesized four different types of chalcone derivatives and demonstrated in vitro bioactivities. We divided these derivatives into two groups of chalcones on the basis of similar substituents on the aromatic rings, and we tested cell viability and proliferation potentials, which indicated that the methoxy substituent on the A ring could enhance cytotoxicity and antiproliferation potential depending on the chalcone concentration. We also investigated osteogenic differentiation of C2C12 cells by ALP staining, the early marker for osteogenesis, which demonstrated that the chalcones could not only induce activity of BMP-2 but also inhibit the activity of noggin, a BMP antagonist. In addition, chalcone bearing hydroxyl groups at the 2-, 4-, and 6-position on the A ring inhibited treptococcus mutans growth, a major causative agent of dental caries. Therefore, we concluded that the chalcone derivatives synthesized in this research can be good candidates for therapeutic agents promoting bone differentiation, with an expectation of inhibiting S. mutans, in dentistry.

[Purpose] The purpose of this study was to investigate the effect of trunk stabilization circuit exercise using a rubber mat on the thickness and white area index of the transverse abdominis in college students in their 20's. [Subjects and Methods] The subjects were randomly assigned to the experimental group and the control group. Those exercises were provided to twenty eight healthy adults in their 20s for four weeks and the thickness of transverse abdominis was measured before study and after 4 weeks. [Results] There were significant differences in interaction between two groups. Paired t-test for thickness and white area index of transverse abdominis showed statistically significant differences to experimentals than controls. Independent t-test for white area index of transverse abdominis also showed statistically significant differences to experimentals than controls. [Conclusion] In conclusion, there was statistically significant difference between the effects of trunk stabilization circuit exercises on back muscles according to types of the surface, and it is expected that this result will be used as a basic data in studies of abdominal muscle stabilization in the future.

In this study, trihydroxychalcone derivatives were synthesized and evaluated for their potential antidiabetic effects in a cell-culture system and a diabetic mouse model in vivo. Some of them increased fatty acid oxidation (FAO) in C2C12 myotubes without affecting the cell viability. In addition, some trihydroxychalcone derivatives, including chalcone 13, facilitated AMP-activated protein kinase (AMPK) activation. Chalcone 13 administration to high-fat diet (HFD)-induced diabetic mice improved glucose tolerance, increased muscle FAO, and reduced fat accumulation in the liver and skeletal muscles. These results suggest that some chalcone derivatives, particularly chalcone 13, might be potential therapeutic agents for the treatment of diabetes.

A series of diamine-cored tetrastilbene (DTS) derivatives bearing various aliphatic and aromatic substituents was designed and synthesized for use as solution-processed hole transport layers (HTLs) in organic light emitting diodes (OLEDs). The chemical structures of the DTS derivatives were strategically designed to increase solubility in organic solvents as well as to avoid self-crystallization, and thus ensure a stable morphology under Joule heating while maintaining efficient hole transport capabilities. The five DTS derivatives, composed of different conjugation structures, yielded reasonably good hole transport behavior with a marginal charge carrier mobility of ∼10−5 cm2V−1s−1, which is similar to that of vacuum-deposited N,N′-bis(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (NPB). Due to the high glass transition temperatures of the DTS derivatives, this satisfactory charge transport behavior and smooth surface morphology were conserved up to 180 °C. Green OLEDs were prepared using tris-(8-hydroxyquinoline) aluminum (Alq3):C545T as the emission layer, and the OLED performances of the solution-processed DTS HTLs and the vacuum-deposited NPB HTL were compared. A high luminance efficiency of 11.5 cd A−1 was obtained for one solution-processed DTS HTL, which exceeds that of the NPB HTL (10.01 cd A−1). Furthermore, the DTS HTLs enabled a stable OLED operation, with double the accelerated half-life of the NPB-based device.

Accurately estimating the government spending multiplier is important so that fiscal policies can be used appropriately when recessions hit the economy. To fill the gap between the frontier research of calculating the government spending multiplier and current Korean research, and to estimate a more accurate multiplier in Korea, we construct a government spending news series in Korea based on Fisher and Peters (2010) by exploiting a market-weighted sum of excess stock returns of military contractors in Korea. We then use this military spending news series and estimate a structural VAR model to evaluate the effects of government spending. As a result, GDP and government spending show statistically significant responses to military spending news shocks. The accumulated government spending multiplier peaks after four quarters, and the five-year cumulative multiplier is calculated as 1.27. For a robustness check, different types of VAR models are tested and results are qualitatively similar.

[Purpose] This study examined the impact of wearing a functional foot orthotic on the pelvic angle of young adults who have flatfoot. [Subjects and Methods] A total of 15 college students diagnosed with flatfoot were included in the study. Changes in the pelvic angle in the stance period during walking before and after orthotic use were measured using a VICON Motion System (VICON, Hansung, Korea). The data were analyzed using SPSS 12.0 for Windows. [Results] In the experimental group, the pelvic angle during the mid-stance and mid-swing periods of the gait cycle significantly decreased on the left and right sides after wearing the orthotic, compared to the measurements taken before orthotic usage. The pelvic angle change on the left and right sides also decreased after wearing the orthotic, though this difference was not significant. [Conclusion] The pelvic angle of college students with flatfoot decreased after they wore orthotics. This implies that wearing orthotic shoes can greatly benefit individuals during normal walking by promoting passive changes that decrease the pelvic angle.

[Purpose] The purpose of this study is to examine the effects of inspiratory diaphragm breathing exercise and expiratory pursed-lip breathing exercise on chronic stroke patients' respiratory muscle activation. [Subjects and Methods] All experimental subjects performed exercises five times per week for four weeks. Thirty chronic stroke patients were randomly assign to an experimental group of 15 patients and a control group of 15 patients. The experimental group underwent exercises consisting of basic exercise treatment for 15 minutes and inspiratory diaphragm breathing exercise and expiratory pursed-lip breathing exercise for 15 minutes and the control group underwent exercises consisting of basic exercise treatment for 15 minutes and auto-med exercise for 15 minutes. The activation levels of respiratory muscles were measured before and after the experiment using MP 150WSW to obtain the results of the experiment. [Results] In the present study, when the pulmonary functions of the experimental group and the control group before and after the experiment were compared, whereas the experimental group showed significant differences in all sections. In the verification of intergroup differences between the experimental group and the control group before and after the experiment. [Conclusion] The respiratory rehabilitation exercise is considered to be capable of inducing positive effects on stroke patients' respiratory muscles through diaphragm breathing exercise and lip puckering breathing exercise.

We provide a theoretical framework, with empirical evidence, where monetary policy effects become stronger during periods of heightened uncertainty in productivity. Higher aggregate and idiosyncratic productivity volatility induce firms, which are constrained by information capacity, to allocate more attention to productivities and less to the monetary policy shock. This makes firms under-react to monetary policy actions, which increases real effects of monetary policy shocks. A threshold vector autoregression, which incorporates instrumental variables to identify the monetary policy shock, finds that monetary policy shocks have stronger impacts on output when uncertainty, as measured by VIX, is high.

Tetrahedral structures comprising Sn-cored materials with five different types of substituents were synthesized. For the substituents, we employed methyl and tert-butyl as aliphatic groups, and naphthyl and phenyl as aromatic groups. The bandgap is in the range of 3.28 – 3.56 eV. The All the compounds with substituents showed bathochromical photoluminescence characteristics and exhibited aggregation-induced emission characteristics. Specifically, the compounds with aromatic substituents prohibited side-chain packing and π-π stacking. The energy levels of the highest occupied and lowest unoccupied molecular orbitals were measured to be 5.5 – 5.75 and 2.0 – 2.37 eV, respectively. The maximum luminance efficiencies and power efficiencies of the Sn-cored compound-based organic light-emitting diodes (OLEDs) were 0.38 – 0.71 cd/A and 0.15 – 0.28 lm/W. Therefore, it is expected that Sn-cored compounds with a tetrahedral structure, especially those containing aromatic substituents, can be used as an active material in blue OLEDs for prohibiting side-chain packing and π-π stacking.

[Purpose] This study investigated the effects of proprietary foot orthotics in young adults with flatfoot to determine changes in the ankle joint angle in the coronal plane during the midstance phase. [Subjects and Methods] The subjects were 15 college students diagnosed with flatfoot. Changes in the ankle joint angle in the coronal plane in the midstance phase were measured using the Vicon Motion System before and after use of the orthotic. The data were analyzed using Statistical Package for the Social Sciences Win 16.0. [Results] The subjects showed significant increases in left and right ankle joint angles in the coronal plane during the midstance phase of the gait cycle after use of the orthotics. However, the difference between the left and right ankle joint angles showed no significant change, even though the difference increased after use of the orthotics. [Conclusion] Young adults with flatfoot showed increased ankle joint angles after use of the orthotics. This suggests that orthotic footwear can shape the plantar arch and affect the ankle joint, and that constant use of orthotics would cause a dynamic change in normal walking.

A numerical measure of central bank credibility, which can be incorporated into a New Keynesian model under bounded rationality, is proposed and analyzed. This measure arises mainly due to the existence of the drifts in private long-term predictions, which are different from those of the central bank. It is shown that central bank credibility matters for macroeconomic stability. As the credibility increases, macroeconomic variables vary less. This generates endogenous volatility changes. Lastly, the magnitude of response of inflation to monetary policy depends on the level of credibility. This suggests that ignoring credibility changes might leads to overestimate of the cost of disinflation.

Korean Abstract: 본 연구에서는 우리나라 노동시장 이중구조의 실태와 원인과 관련한 기존 연구들을 살펴보고, 우리나라 노동시장의 이중구조 실태를 실증적으로 분 석하였다. 또한, 노동시장 이중구조 심화의 원인을 분석하고 해외 사례를 참고하여 노동시장 이중구조 완화를 위한 정책 방향과 과제를 제시하였다. 실증 분석에 따르면 1980년대 후반 이후 대-중소기업간 임금격차는 추세 적으로 확대되어 왔다는 점을 확인할 수 있었다. 고용형태별 임금격차는 2000년 이후 격차가 확대되다가 2007년 기간제 사용 제한과 비정규직 차별 시정을 포함한 비정규직법이 통과된 이후 완화되는 것으로 나타났다. 또한 노동시장 이중구조의 뚜렷한 특징으로 볼 수 있는 부문 간 단절이 심화하여 대-중소기업간 이동 비율이 2000년대 이후 줄곧 하락해왔다는 점을 확인하 였다. 유럽 주요국의 정책대응 사례 등에 비추어 우리나라 노동시장의 이중구조 를 완화하기 위해서는 크게 세 가지 방향으로 정책을 추진할 필요가 있다. 첫째, 대-중소기업간 공정한 거래가 이루어지도록 시장 규칙을 정착시키는 제도들의 실효성을 높일 필요가 있다. 둘째, 1차 노동시장의 폐쇄성과 경직 성을 완화하기 위해 기업 수준을 넘어서 산업이나 업종 수준에서 임금이 결 정되는 시스템을 고려할 필요가 있다. 셋째, 우리나라의 저임금노동계층의 경제적 안전을 보장하기 위해 부작용을 보완해 가서 최저임금인상과 근 로기준 적용과 같은 노동시장 제도를 개선하고 사회보험의 사각지대 축소 와 보편적인 소득지원 제도를 정착시킬 필요가 있는 것으로 판단된다. Englishs Abstract: This paper reviews the previous literature regarding the state and causes of labor market duality in Korea, provides brief empirical evidence on the existence of labor market duality, and suggests possible remedies for resolving the duality based on the experiences from four European countries which differ in the severity of the labor market duality. We confirm the existence of the duality based on the wage gap and immobility in two dimensions: large-small firms and permanent-temporary positions. Lastly, we suggest some countermeasures to mitigate the duality problem. First, the government need to supervise the contracts between large and small firms to enhance fairness in the contracts. Second, employers and unions may consider a new wage negotiation system in which wages can be determined collectively within an industry. Third, it is necessary to remove blind areas in social insurance system and provide universal income support programs for low-income employees to guarantee the economic security.

A novel 56 π-electron fullerene acceptor material, benzocyclobutene-C 60 bisadducts (BCBCBA), was developed via the [2+2] cycloaddition of in-situ generated benzyne with C 60 to raise the lowest unoccupied molecular orbital (LUMO) energy level of the fullerene. This four-membered linkages to C 60 of BCBCBA resulted in the fullerene bisadducts with very addends, thus minimizing the adverse effects of their regioisomers on the intermolecular packing between fullerene bisadducts. In addition, the LUMO level of BCBCBA was as high as −3.70 eV, which is 0.16 eV higher than that of phenyl-C 61 -butyric acid methyl ester (PCBM) (−3.86 eV). This result indicates the significant potential for improving open-circuit voltage ( V OC ) values in polymer solar cells (PSCs). The poly(3-hexylthiophene) (P3HT):BCBCBA based PSCs show V OC of 0.73 and power conversion efficiency (PCE) of 3.51%, which are similar to the P3HT:bis-PCBM based PSCs.

Structures of ten conformational isomers of methylene bridge-monosubstituted tetramethoxycalix[4]arenes, 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetramethoxy-2-ethylcalix[4]arene (1), and methyl 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetramethoxycalix[4]arene-2-carboxylate (2) were optimized by quantum mechanical mPW1PW91/6-31G(d,p) (hybrid Hartree–Fock density functional) calculations. The total electronic and Gibbs free energies of the various conformations (cone, partial cone, 1,2-alternate, and 1,3-alternate) of 1 and 2 were analyzed. The cone (equatorial) and partial cone (equatorial) conformers were disclosed to be the most stable among all the isomers of 1 and 2. The calculated structures agreed well with the experimental results. The IR spectra were calculated at the mPW1PW91/6-31G(d,p) level for the most stable conformer of each methylene bridge-monosubstituted tetramethoxycalix[4]arene.

Department of Chemistry, Chung-Ang University, Seoul 156-756, KoreaReceived February 6, 2014, Accepted February 19, 2014Key Words: 2-(Biphenyl-4-yl)-1-(4-bromophenyl)-1-phenylethene, Single-crystal structure, Horner–Wad-sworth–Emmons reactionVarious π-conjugated organic compounds have been ap-plied in a wide range of optoelectronic devices such asorganic field-effect transistors, organic photovoltaic cells,and organic solid-state lasers.

[Purpose] The purpose of this study was to determine whether exercises using proprioceptive neuromuscular facilitation (PNF) scapular and pelvic patterns might decrease the pain index and increase the lumbar flexibility of obese patients with low back pain. [Subjects and Methods] Thirty obese patients with low back pain were randomly assigned to an experimetal group (n=15) and a control group (n=15). The exercise program of the experimental group consisted of scapular patterns (anterior depression − posterior elevation) and pelvic patterns (anterior elevation − posterior depression). The control group performed neutral back muscle strengthening exercises. Over the course of four weeks, the groups participated in PNF or performed strengthening exercises for 30 minutes, three times per week. Subjects were assessed a pre-test and post-test using measurements of pain and lumbar flexibility. [Results] The results show that lumbar flexion and lumbar extension significantly improved in the experimental group, had significant improvement and that the Oswestry Disability index (ODI) significantly decreased. However, there were no significant changes in the control group. The experimental group also showed significant differences in the pain index and lumbar flexibility from the control group. [Conclusion] This study showed that PNF can be used to improve pain index rating and lumbar flexibility. The findings indicate that the experimental group experienced greater improvement than the control group by participating in the PNF lumbar stabilization program.

[Purpose] We investigated how diaphragm respiration exercises can affect pulmonary function in long-term male smokers in their twenties. [Subjects and Methods] Twenty-eight healthy males between 20 and 29 years of age were randomly divided into an experimental and a control group (14 members each). The experiment was conducted during 30 min sessions, 3 times a week for 4 weeks. The experimental group performed diaphragm respiration exercises and the control group performed exercises using MOTOmed. Pulmonary function (tidal volume, breathing capacity, inspiratory reserve volume, inspiratory capacity, and expiratory reserve volume) was evaluated and analyzed before and after the experiment. [Results] Our results revealed significant increases in tidal volume, inspiratory reserve volume, inspiratory capacity, and breathing capacity in the experimental group. These increases were greater in the experimental group than in the control group. [Conclusion] In our study, the experimental group which performed diaphragm respiration exercises showed a greater improvement in pulmonary function compared with the control group. It is hypothesized that greater improvement in pulmonary function is expected if diaphragm respiration exercises are implemented taking into account the age of the smokers.

[Purpose] The purpose of this study was to examine the effects of a functional foot orthosis on the knee angle in the sagittal plane of college students in their 20s who had flatfoot. [Subjects and Methods] The subjects of this study were 20 college students diagnosed as having flatfoot. The variations of their knee angle (Q-angle) in the sagittal plane during the stance phase were measured using the VICON Motion System (Vicon, Hansung, Korea) before and while wearing a foot orthosis. The experimental data were analyzed using SPSS 12.0 for Windows. [Results] The Q-angle in the test group during the stance phase showed statistically significant declines on the right and left sides while wearing the foot orthosis during the gait-phases of loading response and midstance. During initial contact, terminal stance, and preswing, the Q-angle also decreased on the right and left sides after wearing the foot orthosis, but the changes were not statistically significant. [Conclusion] The college students with flatfoot exhibited declines in the Q-angle in the sagittal plane while wearing a foot orthosis. In this regard, the application of active gait training using orthotic shoes for long hours is likely to help individuals with flatfoot to achieve normal gait.

A method to control activation of a DNA nanodevice by supplying a complementary DNA (cDNA) strand from an electro-responsive nanoplatform is reported. To develop functional nanoplatform, hexalayer nanofilm is precisely designed by layer-by-layer assembly technique based on electrostatic interaction with four kinds of materials: Hydrolyzed poly(β-amino ester) can help cDNA release from the film. A cDNA is used as a key building block to activate DNA nanodevice. Reduced graphene oxides (rGOs) and the conductive polymer provide conductivity. In particular, rGOs efficiently incorporate a cDNA in the film via several interactions and act as a barrier. Depending on the types of applied electronic stimuli (reductive and oxidative potentials), a cDNA released from the electrode can quantitatively control the activation of DNA nanodevice. From this report, a new system is successfully demonstrated to precisely control DNA release on demand. By applying more advanced form of DNA-based nanodevices into multilayer system, the electro-responsive nanoplatform will expand the availability of DNA nanotechnology allowing its improved application in areas such as diagnosis, biosensing, bioimaging, and drug delivery.

The hydrogenolysis of polymer-bound arenesulfonates by 2-propylmagnesium chloride was performed through reductive cleavage of the C-S bond in the presence of a nickel catalyst. The reaction underwent in the highest efficiency by adding 15 equiv of the nucleophile in two additions with in THF. Various unfunctionalized naphthalene, biphenyl, and stilbene derivatives were produced in good yields by the traceless sulfonate linker system at room temperature.

The effects of derivatives in unsymmetrical distyrylbiphenyl compounds on the performance of blue organic light emitting diodes (OLEDs) were investigated. Organic compounds based on unsymmetrical distyrylbiphenyl were synthesized with respect to the numbers and locations of methyl and tert-butyl groups. The main peak wavelength of photoluminescence (PL) spectra in a solid state and the difference in the PL main peak between the solid and solution states decreased as the number of tert-butyl groups in unsymmetrical distyrylbiphenyl decreased. Furthermore, discernible diffraction peaks and roll-like grain were not observed as the number of tert-butyl groups increased, indicating that the tert-butyl group prohibits the formation of a planar structure and thus reduces chromophoric π–π interaction and fluorescence quenching. The luminance value of OLEDs used as an active layer in the tert-butyl–tert-butyl functional group was as high as 1860 cd/m2 at a current density of 150 mA/cm2 due to the reduction in fluo...

The characteristics of resin matrices containing 2,2-bis[4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA) alternatives and spiro orthocarbonate (SOC) were examined to produce dental restorative composites exhibiting lower curing shrinkage and better mechanical strength than the commercially available dental composites. Bis-GMA alternatives were prepared by replacing the hydroxyl groups in Bis-GMA with alkoxy groups. Various SOCs that showed the expected volume expansion during the curing reaction caused by the ring opening reaction were added to Bis-GMA alternatives for a further decrease in curing shrinkage. The curing shrinkage of the dental composites containing Bis-GMA alternative and SOC was always lower than that of the dental composite used as the control, which contained 70 wt% Bis-GMA and 30 wt% triethylene glycol dimethacrylate (TEGDMA) as the resin matrix. Furthermore, the mechanical strength of the dental composites prepared from the 2,2-bis[4-(2-methoxy-3-methacryloyloxy propoxy)phenyl]propane (Bis-M-GMA) mixture containing approximately 10 wt% SOC was higher than that of the dental composite used as the control.

), have been adopted as elect rophilic substrates in these reactions. Diverse organometallic nucleophiles, such as organo-boronic acids, organostannanes, organozincs and organomag-nesiums, have also been successfully applied as nucleophilic substrates.While many transition metal catalysts have been examined to promote the C-C couplings, nickel- and palladium complexes have occupied a predominant place as the versatile catalysts. The activity of the transition-metal catalysts strongly depends on the combination of ligand and metal.

Unfunctionalized biaryl compounds were parallelly and combinatorially prepared by the traceless hydrogenolysis of biarylsulfonates supported on pentaerythritol. The hydrogenolysis using 2-propylmagnesium chloride in the presence of dppfNiCl2 efficiently generated corresponding biaryl derivatives without any memory of the support. The strategy using pentaerythritol as a small soluble support was disclosed to have a potential to combine the benefits of both SPOS and solution-phase reaction with fast reaction rate, facile isolation of intermediates, easy analysis of intermediates and atom economical manner. The novel tetrapodal support is expected to be an efficient substitute for polymeric supports in many circumstances.

Quantum mechanical properties of unsymmetrical and unfunctionalized trans-stilbene derivatives 1-3, which had been prepared by solid-phase parallel syntheses, were characterized using mPW1PW91/6-311G(d,p) (hybrid HF-DF) calculations. The total electronic energies, normal vibrational modes, Gibbs free energies, and HOMOs and LUMOs of sixteen different structures from three different groups were analyzed. The energy differences between the HOMOs and LUMOs of the various unsymmetrical trans-stilbenes are in accord with the maximum absorption peaks of the experimental UV spectra of 1-3. The calculated normal vibrational modes of 2l were comparable with its experimental IR spectrum. The π-conjugation in the para-connected biphenyl group of 2 is better than the one in the metaconnected biphenyl group on the shorter side of 3.

A small library of fluorescent and unsymmetrical trans-stilbene compounds was efficiently produced by a solid-phase synthetic approach using the sulfonate-based traceless linker system. Nickel(0)-catalyzed cleavage/cross-coupling of polymer-bound stilbenesulfonates with aryl Grignard reagents generated the desired trans-stilbenes at high yield by the multifunctional release facilitating the additional diversification of the library. The luminescent properties of trans-stilbenes are assessed, and the influence of alkyl substituents on their photophysical properties is discussed.

Nickel N-heterocyclic carbene (NHC) catalytic system prepared in situ by the reaction of Ni(acac)(2) with NHC precursor efficiently catalyzed the cross-coupling reaction of alkoxysulfonylarenes with methyl, neopentyl, and benzyl Grignard reagents at ambient temperature.

Organic fluorine chemistry produces many useful products. This paper elucidates the reaction of ethyl-4,4- difluoro-2-iodo-5-oxo-5-phenylpentanoate (2) with primary amines in a one-pot scheme. The reaction produced a series of β-fluoropyrrole derivatives at ambient temperatures. In this reaction, the less bulky the primary amine the higher was the resultant yield. When (2) and aqueous methylamine (40%) were allowed to react below 0 oC, 5-(ethoxycarboxyl)-1-methyl-3,3-difluoro-2-hydroxy-2-phenylpyrrolidine, an intermediate molecule for 2-ethyl-4-flouro-1-methyl-5-phenylpyrrole-2-carboxylate (5), was isolated first. Then, (5) reacted with hydroperchloric acid and acetic anhydride to form 5-(ethoxycarboxyl)-1-methyl-3,3-difluoro-2- phenylpyrrolinium perchlorate (6), which was converted to 2-ethyl-4-flouro-1-methyl-5-phenylpyrrole-2- carboxylate gradually in the presence of a base. Our experiments demonstrate that the formation of 2-ethyl-4- flouro-1-methyl-5-phenylpyrrole-2-carboxylate occurs via both one-pot schemes and stepwise pathways, depending on the reaction conditions. The isolation and characterization of the isolated intermediate (6) suggest an anionic pathway for this reaction.

Application of a novel sulfonate-based traceless multifunctional linker system using pentaerythritol as a tetrapodal soluble support was demonstrated using liquid-phase parallel and combinatorial preparation of biphenyl and terphenyl compounds. Nickel-catalyzed reactions of pentaerythritol tetrakis(arenesulfonate)s with arylmagnesium bromides generated the desired products in sufficient yields through reductive cleavage/cross-coupling of the C-S bond. Homogeneous pentaerythritol-supported reactions could be accomplished using less nucleophile with shorter reaction periods than could the corresponding heterogeneous polymer-supported reactions. This liquid-phase approach using a small polyfunctionalized support combines advantages of solution-phase and solid-phase syntheses by allowing high reactivity, high atom economy, simple isolation, and real-time monitoring of the reaction progress.

[Purpose] This study aims to examine stroke patients’ changes in dynamic balance ability through stair gait training where in proprioceptive neuromuscular facilitation (PNF) was applied. [Subjects and Methods] In total 30 stroke patients participated in this experiment and were randomly and equally allocated to an experimental group and a control group. The experimental group received exercise treatment for 30 min and stair gait training where in PNF was applied for 30 min and the control group received exercise treatment for 30 min and ground gait training where in PNF was applied for 30 min. For the four weeks of the experiment, each group received training three times per week, for 30 min each time. Berg Balance Scale (BBS) values were measured and a time up and go (TUG) test and a functional reach test (FRT) were performed for a comparison before and after the experiment. [Results] According to the result of the stroke patients’ balance performance through stair gait training, the BBS and FRT results significantly increased and the TUG test result significantly decreased in the experimental group. On the contrary, BBS and FRT results did not significantly increase and the TUG test result did not significantly decrease in the control group. According to the result of comparing differences between before and after training in each group, there was a significant change in the BBS result of the experimental group only. [Conclusions] In conclusion, the gait training group to which PNF was applied saw improvements in their balance ability, and a good result is expected when neurological disease patients receive stair gait training applying PNF.

Neopentyl arenesulfonates reacted with primary alkylmagnesium halides in the presence of to produce the corresponding alkylarenes. The efficiency of this coupling reaction considerably depends on the nature of catalyst and solvent. Highest yield was obtained by using three equivalents of Grignard reagent to a mixture of and arenesulfonate in refluxing . This reaction represents a novel method allowing the efficient and creative substitution of sulfur-containing groups in aromatic compounds. It also shows that the alkyloxysulfonyl group might be a suitable alternative to halides and triflate in some circumstances.