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Vector beams, structured optical beams with nonuniform polarization distributions over the cross-section, have been recently found to be more beneficial than the scalar beams to many applications r...

We report on an etching-based fabrication method for conical core-maintained fiber tapers with adiabatic tapering angles, and discuss its adiabatic mode evolution compared to the conventional pulled fibers over the O-/C-bands. The far-field pattern from the etched fiber shows that the fundamental mode is maintained throughout the tapers.

We report the generation of a supramolecular structure of 3.2-ns-spaced multiple cavity solitons via the interplay between the Kerr effect and Brillouin scattering in a fiber Kerr resonator. Pulsed pumping and continuous-wave pumping are compared.

We demonstrate the manipulation of quasi-continuous-wave background in a mode-locked fiber laser using optoacoustically excited acoustic impulses. The properties of the resulting intensity modulations of the background can be tailored by changing the fiber parameters.

We use intense optoacoustic interactions involving the acoustic resonances confined in high-quality 51-cm-long silica microfibers to stabilize the harmonic mode-locking of fiber lasers at gigahertz repetition rates, which is controllable via tuning the microfiber thickness.

Noise-like quasi-continuous-wave background (qCWB) in a mode-locked fiber laser mediates various multi-pulse dynamics via long-range inter-pulse interactions. This raises a possibility to control multi-pulse phenomena through manipulation of the qCWB, while it has been rarely studied yet. Here, we investigate the qCWB engineering by imposing optomechanically induced impulsive intensity modulations on the qCWB. The mode-locked pulses excite electrostrictively several transverse acoustic resonance modes inside the fiber cavity, which eventually leads to the formation of sharp qCWB modulations regularly spaced in the time domain. In particular, we experimentally demonstrate that the characteristics of the optomechanical qCWB modulations can be adjusted by controlling the in-fiber optomechanical interactions via changing the structure of the fiber core, cladding, and coating. Our observations are supported by directly measured forward stimulated Brillouin scattering spectra of the intracavity fibers.

Photonic devices exhibiting all-optically reconfigurable polarization dependence with a large dynamic range would be highly attractive for active polarization control. Here, we report that strongly polarization-selective nonlinear optomechanical interactions emerge in subwavelength waveguides. By using full-vectorial finite element analysis, we find that at certain core ellipticities (aspect ratios) the forward simulated light scattering mediated by a specific acoustic mode is eliminated for one polarization mode, whereas that for the other polarization mode is rather enhanced. This intriguing phenomenon can be explained by the interplay between the electrostrictive force and radiation pressure and turns out to be tailorable by choice of waveguide materials., Comment: 5 pages, 5 figures

A variety of nonequilibrium multi-pulse states can emerge in a mode-locked laser through the interactions between the quasi-continuous-wave background (qCWB) and optical pulses inside the laser cavity. However, they have been long regarded as unpredictable and hardly controllable due to the noise-like nature of the qCWB, and relevant previous studies thus lack a clear understanding of their underlying mechanisms. Here, we demonstrate that the qCWB landscape can be manipulated via optoacoustically mediated interactions between the qCWB and mode-locked pulses, which dramatically alters the behaviors of multi-pulse dynamics in unprecedented manners. In this process, impulsive qCWB modulations are created at well-defined temporal locations, which act as the point emitters and attractive potentials for drifting pulse bunches and soliton rains. Hence, we can transport a single pulse bunch from a certain temporal position to another on the qCWB, and also make the soliton rain created and collided exclusively at specific temporal locations, in sharp contrast to the conventional cases. Our study opens up new possibilities to control the nonequilibrium multi-pulse phenomena precisely in the time domain, which would not only help the observation and clear understanding of undiscovered features of multi-pulse dynamics but offer a practical means of advanced optical information processing., Comment: 23 pages, 6 figures, 1 table

PURPOSES : This paper aims at the implementation of a balanced scorecard that can be widely applied to modern business management for use in the public road management sector. METHODS : This study applied the newly developed LOS-based balanced scorecard system instead of a traditional Key Performance Index (KPI) for better decision making in asset management planning. As an evaluation technique, a" hierarchical alignment and cascading method" is also suggested. Finally, the suggested system has been empirically applied to a regional government. RESULTS : To provide stable and sustainable road services, the balanced scorecard informs the regional government of needed improvements in its asset management plans regarding budget optimization, structural management, the development of inner-business processes, and human resources. CONCLUSIONS : An LOS-based balanced scorecard for managing road services and organizations in a quantitative manner has been successfully developed and tested through a field study. The developed scorecard is a timely topic and a useful analytical tool for coping with the new phases of an aging infrastructure, tighter budgets, and demand for greater public accountability.

We experimentally demonstrate optomechanically driven nonlinear mechanical intermodal coupling by using high-Q square nano-membranes. Pumping via radiation forces as low as 34 pN, we achieve ultrahigh-efficiency coupling of the first-order mode into the higherorder ones.

An all-optically reconfigurable generation of optical vortices would be highly beneficial to the implementation of next-generation optical communication and advanced information processing. The previously demonstrated approaches based on the parametric nonlinear optical processes, however, have exhibited limited conversion efficiency due to the group velocity mismatch and nonlinear phase shifts, and require the cumbersome preparation of either the optical element or initial seed beam having a non-zero topological charge. Here, we propose and analyze a novel scheme for highly efficient all-optical generation and control of optical vortices based on the dynamic acoustic vortex grating created by forward stimulated intermodal Brillouin scattering in a subwavelength-hole photonic waveguide. The dual-frequency pump beams in two different hybrid optical modes drive an acoustic vortex mode, which transforms a signal in the fundamental optical mode into an optical vortex mode. This scheme not only eliminates the need for the initial preparation of an angular-momentum-carrying medium or an optical vortex seed but also guarantees high modal purity and nearly 100% conversion efficiency assisted by the energy-momentum conservation. We also investigate the feasibility and practicability of the subwavelength-hole waveguides by examining the intermodal conversion efficiency and robustness of guidance of the optical vortices, taking into account the impact of the Kerr-type nonlinear effects on the intermodal Brillouin interactions based on our rigorous full-vectorial analytical theory.

Phytochemical studies on the leaves of Ailanthusaltissima (Simaroubaceae) have not been reported previously.Thus, the authors isolated and identified secondary metabolitesfrom A. altissima. Dried and powdered leaves were extracted with80% aqueous methanol, and the concentrated extract wassuccessively partitioned with ethyl acetate, n-butanol, and water.Four flavonoids were isolated from the ethyl acetate fractionthrough repeated silica gel and octadecyl silica gel columnchromatography. Spectroscopic data including NMR, MS, and IRallowed for identification of the chemical structures as quercetin(1), afzelin (2), quercitrin (3), and isoquercitrin (4). This is the firstreport of the isolation of these compounds from A. altissima. Thefour isolated flavonoids 1–4 as well as solvent fractions (ethylacetate, n-butanol, and water), were evaluated for DPPH radicalscavenging activity.Keywords afzelin · Ailanthus altissima · DPPH assay · isoquercitrin · quercetin · quercitrinIntroductionAilanthus altissima Swingle (Simaroubaceae), also known as tree-of-heaven, is a deciduous tree distributed mainly in China,Mongolia, Japan, and Korea (Feo et al., 2005). The diameter of amature A. altissima tree is about 50 cm with stems grows up to30 m. The upper sides of the leaves of A. altissima are dark green,while the under side is dark red. Flowers of A. altissima appearbeginning from the end of June and the seeds is included in flowerinside of the propeller shape. A. altissima has been used inChinese traditional medicine as a bitter aromatic drug for thetreatment of colds and gastric diseases (Feo et al., 2003; 2005).Some compounds isolated from the root and bark of the planthave been reported to have insecticidal (Kraus et al., 1994),antimalarial (O’Neill et al., 1986; Bray et al., 1987), antitumor(Casinovi et al., 1983), antitubercular (Rahman et al., 1997),nervous depressant (Crespi-Perellino et al., 1988), antiproliferative(Hwang et al., 2002), anti-Epstein-Barr virus (Kubota et al., 1997),alleropathy (Heisey et al., 1990; 1996), anti-inflammatory (Jin etal., 2009), and antioxidant activities (Okunade et al., 2003; Lee etal., 2005; Tamura et al., 2006; Zhang et al., 2007; Rahman et al.,2009). There have been some reports on the isolation of secondarymetabolites from the cortex and roots of A. altissima. However,there are only a few studies that have evaluated the leaves of A.altissima with respect to their biological and phytochemicalproperties. In addition, DPPH assay performed with an alcoholextract of A. altissima leaves showed significant activity. Therefore,this study was initiated to identify the principal antioxidantcompounds from A. altissima leaves.Antioxidants are useful chemical materials for preventingoxidative deterioration of biomolecules and are widely applicableas ingredients of food supplements, cosmetics, and medicines.Many plants contain substantial amounts of antioxidants such asvitamin C, vitamin E, carotenoids, flavonoids and tannins that canbe utilized to scavenge excess free radicals from the human body.Indeed, many researchers have found efficient antioxidants in plants.

Aim of the study Many medicinal plants have been used for treatment of insomnia in Asia. However, scientific evidence and precise mechanism for their sedative-hypnotic activity have not been fully investigated. Thus, we investigated the binding activity of the oriental plant extracts (mainly from Korea and Japan) to the well-known molecular targets for sleep regulation, GABA A and 5-HT 2C receptors. Following the binding assay, sedative-hypnotic effects of the extracts with high affinity were examined in an animal model of sleep. Materials and methods Aqueous and ethanol extracts of 15 medicinal plants were tested for binding at the benzodiazepine site of GABA A receptor and 5-HT site of 5-HT 2C receptor. The sedative-hypnotic effects of selected extracts were evaluated by measuring the sleep latency and sleep duration during pentobarbital-induced sleep in mice after oral administration of extracts. Results In the GABA A assay, the ethanol extracts of licorice and danshen displayed concentration-dependent, high affinity binding, whereas in the 5-HT 2C assay, the ethanol extracts of ginseng and silk tree showed high affinity. Among these extracts we tested previously uncharacterized licorice and silk tree for hypnotic effects. We found the ethanol extracts of licorice and silk tree significantly decreased sleep latency and increased sleep duration in pentobarbital-induced sleep. Conclusions We demonstrate for the first time that licorice and silk tree have the sedative-hypnotic activity possibly by modulating GABA A and 5-HT 2C receptors. We propose that licorice and silk tree might be effective candidates for treatment of insomnia.

We report that extremely polarization-sensitive stimulated Brillouin scattering (SBS) emerges in subwavelength elliptical waveguides when mediated by surface acoustic waves. We find based on the full-vectorial finite element analysis that the SBS driven by a specific surface acoustic wave can be eliminated for one polarization mode, whereas for the other polarization mode, it is kept significant, while such strongly polarization-dependent Brillouin gain has not been observed in conventional SBS by bulk acoustic waves. We explain the origin of these intriguing polarization-selective phenomena in terms of the counter-balance between the photoelastic and moving-boundary effects. Our findings provide a host of unique possibilities of highly efficient all-optical control and stabilization of the polarization state of light.We report that extremely polarization-sensitive stimulated Brillouin scattering (SBS) emerges in subwavelength elliptical waveguides when mediated by surface acoustic waves. We find based on the full-vectorial finite element analysis that the SBS driven by a specific surface acoustic wave can be eliminated for one polarization mode, whereas for the other polarization mode, it is kept significant, while such strongly polarization-dependent Brillouin gain has not been observed in conventional SBS by bulk acoustic waves. We explain the origin of these intriguing polarization-selective phenomena in terms of the counter-balance between the photoelastic and moving-boundary effects. Our findings provide a host of unique possibilities of highly efficient all-optical control and stabilization of the polarization state of light.

As an alternative to conventional Group I and II separation methods (such as adding a chemical agent and ion exchange), melt crystallization processes, zone freezing, and layer melt crystallization were tested for the separation (or concentration) of cesium and strontium fission products in a LiCl waste salt generated from an electrolytic reduction process of a spent oxide fuel. In these melt crystallization processes, impurities (CsCl and SrCl 2 ) are concentrated in a small fraction of the LiCl salt by the solubility difference between the melt phase and the crystal phase. As experimental variables, initial molten salt temperature, crucible rising velocity in the zone freezing case, and cooling air flow rate in the layer crystallization case were used. In the zone freezing process, although the operating time is long (1.7 mm/h of crucible rising velocity) when assuming a LiCl salt reuse rate of 90 wt%, >90% separation efficiency for both CsCl and SrCl 2 was shown. In the layer crystallization process, the crystal growth rate strongly affects the crystal structure and therefore the separation efficiency. At a 25 to 30 l/min cooling air flow rate, 700 to 710°C initial molten salt temperature, and

A lab-scale lanthanide precipitation apparatus, which has a 4 kg/batch size, was installed and tested. By using this lab-scale apparatus, cooxidative precipitation experiments of lanthanides were carried out. As lanthanides, 8 rare-earth elements (Y, La, Ce, Pr, Nd, Sm, Eu, and Gd) were used. By a reaction with oxygen, La, Pr, Nd, Sm, Eu, and Gd were converted to their oxychloride form (REOCl) and Ce, Pr, and Y to their oxide form (REO2, RE2O3). Since these lanthanide oxides or oxychlorides are nearly insoluble to eutectic salt, they were all precipitated by a free settling at the bottom, where about 7 h of precipitation time was required. It was found that under the conditions of 750°C salt temperature, a 12 h sparging time, and 5 L/min oxygen sparging rate, all the used rare-earth elements showed over 99% oxidation efficiency. However, in the case of 800°C temperature, they show over 99% conversion efficiencyonly after 6 h.

Pine mushroom (Tricholoma matsutake Sing.) is an expensive and highly prized delicacy in Korean and Japanese cuisines with its unique flavor and functional properties. The biological activities of pine mushroom juice (soluble solid contents 4.3 o Brix) were evaluated using different tests; DPPH radical scavenging assay for its antioxidant activity, fibrin plate method for fibrinolysis and angiotensin Ⅰ converting enzyme (ACE) inhibitory activity for anti-hypertensive effect. Free radical scavenging activity of the pine mushroom juice was 48.3±2.2% at the concentration of 1.0 mg/mL. The fibrinolytic activity of pine mushroom was about 2 times greater than that of plasmin used as positive control and the activity increased dose-dependently. The pine mushroom juice inhibited ACE activities dose-dependently and IC50 value of ACE activity was 1.03 o Brix. These results suggest that pine mushroom is a healthy delicacy.

We experimentally demonstrate the 3rd-order seeded parametric down-conversion in a silica submicro-wire. Amplification of a 1597.38 nm seed beam is observed upon co-launching a 532.46 nm pump beam in the HE12 mode of the wire.

The purpose of this study was to investigate the effects of p. Linteus and C. militaris supplement on lactate, phosphorous, ammonia, MDA(malondialdehyde), GPX(glutathione peroxidase) and TAS(total antioxidant status) following , and 85% exercise. The 15 male college students were divided into three groups: 5 P. liteus supplied(PL), 5 C. militaris supplied(CM), and 5 placebos supplied(PB) and compared the differences between supplement before and after. Obtained results were as follows: In the exercise performance time, there were no differences in PL, CM and PB groups. Regular supplement of P. linteus or C. militaris partially reduces fatigue induction factors. Also, P. linteus or C. militaris supplement decreases MDA, increases GPX and TAS. Therefore, it can be concluded that P. linteus or C. militaris supplement not only have a pharmacological effect for clinical treatment, but also have a maintenance effects on the tissue oxidant-antioxidant system after exercise.

Symmetric three-layer Al2O3/ZrO2 composites have been prepared by freeze casting and pressureless sintering at 1400-1600o C in air. The layered composite with Al2O3 containing 15 vol.% ZrO2 as an outer layer and containing 20 vol.% ZrO2 as an inner layer, sintered at 1600o C showed the maximum bend strength (300 MPa). Contact damage resistance was superior in layered composites compared with monolithic materials, possibly due to the development of compressive stress in the outer layer.

This study was peformed to investigate the synergistic effects of catechin and ascorbic acid on antioxidative activities of methanol and hexane extracts (500 ppm) from rosemary, sage, oregano, and ginger. Ascorbic acid (200 ppm) and (-)-catechin (200 ppm) could be solubilized in a rice bran oil via a reverse micelles using small amount of water and dioctyl sulfosuccinate as the sufactant. Methanol extracts from rosemary, sage, oregano, and ginger showed the synergistic effects by (-)-catechin. However, methanol extracts showed the synergistic effect by ascorbic acid except that of ginger. The synergistic effects of (-)-catechin on methanol extracts were higher than those of ascorbic acid. Hexane extracts of oregano and ginger showed the synergistic effects by (-)-catechin, and no synergistic effects by ascorbic acid. On the other hand, rosemary and sage showed the synergistic effects by ascorbic acid and no synergistic effects by (-)-catechin.

The purpose of this study was to evaluate the effects of low calorie meal substitute and weight control preparation containing dietary fibers, -amylase inhibitor and hydroxycitrate on the reduction of body weight and visceral fat in obese women. Sixteen pre-menoposal healthy women (age: 20∼50 y, body mass index >25) who were living in the Daejeon area participated in this study. We replaced one meal of the subject with low calorie meal substitute and fed the weight control preparation twice a day for 9 weeks. Anthropometric indices, body composition, dietary intake and stool movements were investigated every 3 weeks during the dietary intervention. The blood was collected before and after the dietary intervention. Results are as follows: 1) The subjects` body weight, body fat, BMI, waist, hip and abdominal adipose tissue decreased gradually and significantly between 3rd and 9th week after intervention. 2) The levels of fasting blood glucose, triglyceride and cholesterol, the indicators of liver dysfunction such as activities of ALT, AST and ALP, and bilirubin level were within a normal range and not affected significantly by dietary intervention. 3) Hemoglobin levels increased significantly and blood urea nitrogen level decreased. 4) Their stool movement was improved 5) Compared with the baseline values, calorie intake decreased by 17.5∼21.9% and the intakes of vitamin A, vitamin B2, folate, Ca, Fe, and Zn were below 80% of Korean RDA. In conclusion, the intake of low calorie meal substitute and weight control preparation could be effective in reduction of body weight and fat mass, improving the stool movement and the general physical symptoms.

Fucosterol (2), oxygenated fucosterol, 24-ethylcholesta-4,24(28)-dien-3,6-dione (3), β-sitosterol (1), and daucosterol (4) were isolated from ethyl acetate (EtOAc) fraction of Osmanthus fragrans var. aurantiacus flower by repeated silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatography. The sterol structures were determined based on spectroscopic methods including nuclear magnetic resonance, infrared spectroscopy, fast atom bombardment mass spectrometry, and electron ionization mass spectrometry. Fucosterol (2), oxygenated fucosterol, and 24-ethylcholesta-4,24(28)-dien-3,6-dione (3) are representative sterols mainly isolated from marine algae, but rarely found in land plants. This is the first reported isolation of these sterols from O. fragrans var. aurantiacus. Interestingly, the oxygenated fucosterol (3) isolated inhibited the in vitro growth of the HCT-116 human colon cancer cell line with higher cytotoxic effects than doxorubicin, a well-known cytotoxic drug.

Continuous monitoring of an ECG signal is an important method to evaluate the subject's health state. However, there are many distortion factors in ECG signals, such as motion, respiration, and 60 Hz power noise, and EMI noise. Above all, motion is the most important factor in ECG signal distortion of moving subject and the baseline drift not only causes the estimation error of R-R interval, but changes ST segment level and results in diagnostic errors. Therefore, many researches have been performed to remove the baseline drift in the ECG signal acquisition. But the baseline drift removal algorithms without original ECG signal degradation are difficult to develop, because they affect the low frequency components in general. The accurate evaluation of ECG baseline drift must precede its removal. The main cause of baseline drift is the subject's motion, which can be evaluated by using small 3-axial accelerometer with accuracy and convenience. In this paper, baseline drift in ECG signal caused by motion artifact was quantitatively analyzed and evaluated by using 3-axial accelerometer and classifying posture, posture change, and dynamic motion. The baseline drift was influenced by respiration in static state and motion in dynamic state and the correlation between ECG and acceleration signal can be identified. The low frequency component ratio of ECG baseline drift and high frequency component ratio of acceleration signal were increased by motion and the facts were verified by correlation analysis. These results can be used to minimize the analysis error caused by motion. In addition, the applicability of baseline drift removal algorithm can be decided by the motion detection and the diagnostic error caused by the loss of low frequency component can be minimized. When this result is applied to the portable ECG device with a built-in accelerometer, subject's motion context information can be known and used to manage emergent situation. In this way, the simultaneous acquisition and quantitative analysis technique of ECG and acceleration signal is expected to increase the diagnostic value and give high quality medical information. (5 pages)

Antioxidative effects of ascorbic acid and δ-tocopherol on the oxidation of sardine oil stored at 30°C in the dark has been investigated. It was found from phase diagrams and peroxide values of fish oil/lecithin/water systems that the desirable levels of lecithin and water to solubilize ascorbic acid in the oil were 0.3% (w/w) and 0.1% (w/w), respectively. When ascorbic acid (0.02%) and δ-tocopherol (0.4%) were used together, the induction period of fish oil could be lengthened 22-fold, due to their synergism. They could inhibit the production of carbonyl and volatile compounds and oxidative polymerization.

Individual and combined effects of ascorbic acid andδ-tocopherol on the autoxidation of fish oil have been evaluated with the induction period monitored by Rancimat. The antioxidative efficiency of them was found to increase with increasing concentration.δ-Tocopherol and ascorbic acid acted highly synergistic with each other. Whenδ-tocopherol content was varied at a fixed content of ascorbic acid, the synergistic efficiency was generally 100% or more. On the other hand, when ascorbic acid content was varied at a fixed content ofδ-tocopherol, the synergistic efficiency rose sigmoidally with increasing concentration. We concluded that at least 0.01–0.02% ascorbic acid is required to obtain a considerable synergistic effect withδ-tocopherol in stabilizing fish oil.

The effect of water on equilibria for hydrolytic reaction in reversed micelles has been investigated using lipase as a model enzyme. The effect of water on equilibria has been ignored for hydrolase reactions in an aqueous phase. In a reversed micellar system, however, the equilibrium of the lipase reaction was changed when water was added during the hydrolytic reaction. Furthermore, equilibrium fractional conversion is affected by the initial water concentration, being shifted to higher values with higher water concentrations, with other reaction conditions being held constant, indicating that the reaction should be regarded as a two-substrate process. Equations corresponding to a two-substrate, second-order reversible model are derived and used for further analysis. The progress curves predicted from the rate equations agree very well with the experimental results under various reaction conditions. The values of the molar ratio of water to surfactant (R) which maximize the initial reaction rate and maximum fractional conversion is predictable from the derived rate equations and the resulting relationship between R and the kinetic constants.