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Novel enzyme source is essential in biomimetic synthesis. Use of peanut peroxidase in mediation of oxidative polymerization of phenolic compounds is meager. In this study, the 5 day-germinated peanut embryos were homogenized, centrifuged to collect supernatant and (NH4)2SO4 fractionated, the 40–75% saturated fraction exhibited most peroxidase activities. After UF-concentration between MWCO 300 and 10 kDa, Sephacryl S300 gel filtration and DEAE-Sephadex A25 ion-exchange, a 50.6-fold-purified peroxidase with 32 kDa in SDS-PAGE analysis was obtained. The freeze-dried and pulverized into powder (GPEP) bearing potent peroxidase activities was used in biomimetic resveratrol dimerization. In a semi-continuous system mediated by 0.5 g GPEP suspended in phosphate buffer (pH 7.4) with continuous feedings of resveratrol dissolved in acetone and aqueous H2O2 solution for 150 min, all added resveratrol reacted. After subjecting the reactant to SPE C18 cartridge clean-up, semi-HPLC purification and NMR 1- and 2D spectroscopic elucidation, a dimeric product was identified as δ-viniferin with ca. 60% of recovery. The δ-viniferin exhibited potent trolox equivalent antioxidant capacity as did BHT. It is of merit to demonstrate GPEP as a potential peroxidase source enabling scalable biomimetic production of δ-viniferin.

In this manuscript, reactions of γ-benzyloxy vinylogous urethanes under LDA deprotonation condition undergoing an [1,2]-Wittig rearrangement, followed by the lactonization to provide γ-benzyl vinylogous urethane lactones were studied. Those vinylogous urethane lactones can be facilely transformed into γ-benzyl butenolides. The easy operation of [1,2]-Wittig rearrangement/lactonization in our system, following the swift removal of pyrrolidine moiety in providing clear targets of various γ-benzyl butenolides demonstrated the true advantage of our studies, since previous [1,2]-Wittig rearrangement studies would normally provide products either lack of or not easy to foresee their synthetic applications. Applications of resulting γ-benzyl butenolides were concisely demonstrated in the formal synthesis of maculalactone A, synthesis of BCD ring of planchol C and the total synthesis of γ-lycorane.

The anti-selective aldol reaction of chiral alcohol-substituted γ-benzyloxy vinylogous urethanes is described. The use of (1S,2R,4R)-1-(hydroxydiphenylmethyl)-7,7-dimethylbicyclo[2,2,1]-heptan-2-ol as a chiral auxiliary in the aldol reaction of a vinylogous urethane enolate was found to provide anti-products in good yields with moderate to excellent enantioselectivities. The major anti-vinylogous urethane lactones were transformed into 3-benzyloxyl-4-hydroxylalkan-2-ones in good yields.

Along with clinical benign prostatic enlargement (BPE) management, searching for dietary supplements to relieve and/or prevent syndrome is needed. In this study, the orchiectomized Sprague-Dawley rats were fed with diets supplemented with bio-elicited peanut sprout powder (BPSP) and testosterone injected to mediate BPE. The mediated prostate/body ratio increase was significantly inhibited by diets supplemented with 3.2 g BPSP kg−1 bw. Prostatic catalase and superoxide dismutase activities of the rats fed with 3.2 and 6.4 g kg−1 bw were significantly higher than rats fed with 0 g kg−1 bw. As BPSP subjected to extraction, purification and instrumental elucidation, three new natural compounds were assigned and their antioxidative capacities at 100 µM were equivalent to 93.6, 83.9 and 84.7 µM of trolox, respectively. The new identified potent antioxidants along with the known antioxidative, anti-inflammatory and phytoestrogenic stilbenoids in BPSP-supplemented diets leading to the observed inhibitory effectiveness on testosterone-mediated BPE is of merit.

Biosynthesis of peanut stilbenes, including resveratrol as the secondary metabolites, could be enhanced by subjecting the kernels to germination and wound-stress. Investigations of the bio-elicited peanut sprout powder (BPSP) addressed on characterization of the comprising stilbenes and effectiveness in longevity extension deserves intensive research. In this study, peanut kernels were subjected to germination and wound-stress in preparation of BPSP. The methanol extracts of BPSP were medium pressure liquid chromatographic (MPLC) fractionated and semi-preparative HPLC recovered and followed by instrumental identification and biological activity determinations of the isolated stilbenes. In longevity experiments, 16 female 11-mon-old BALB/c mice and both genders of 12-mon-old ICR mice were daily fed with BPSP supplemented diets at doses of 0, 0.1 and 0.5 g BPSP/kg bw for 750 and 762 days, respectively. Based on chemical characterization, enriched quantity of stilbenes in the BPSP up to ca. 1% (w/w) was detected. Two new stilbene compounds, namely, 4, 5’-dihydroxy-6’’-hydroxymethyl, 6’’-methylpyrano [2’’, 3’’: 3’, 4’] stilbene and 3, 4, 5’-trihydroxy-6’’, 6’’-dimethylpyrano [2’’, 3’’: 3’, 4’]stilbene along with 5 known stilbenes were isolated. The 7 stilbenes exhibited potent antioxidative and antiglycative activities and varied with structure-activity nature. Based on the resultant survival curves and average lifespans of both mouse models, basal diets supplemented with BPSP are effective to extend mouse longevity by a dose dependent manner. It is of merit to demonstrate that peanut kernels as a potent producer could be bio-elicited to biosynthesize a broad spectrum of bioactive stilbenes to prepare BPSP which is effective to extend mouse longevity as science-evidenced by the two long-term animal experiments.

Stereoselective synthesis of 2,3,3,4-tetrasubstituted oxetanes via intramolecular allyl or benzyl anion four-membered ring cyclization of vinylogous urethane derivatives is presented. The resulting products featuring a β-pyrrolidinyl ester at C3 were readily transformed into the corresponding 3-α,β-unsaturated ester substituted oxetanes by Cope elimination reactions.

Highly stereocontrolled total synthesis of dart frog indolizidine alkaloids (–)-167B, (–)-209I, and (–)-223A was accomplished, with a common tricyclic lactone intermediate as the starting compound, in overall yields of 17 %, 14 %, and 17 %, respectively. The C7–C8 bond of the 167B, without a C8 chiral substituent, was formed through ring closure metathesis followed by hydrogenation. In 209I and 223A, which have a C8 chiral substituent, highly substrate-controlled asymmetric radical cyclization was used to form the C7–C8 bond, and the correct stereochemistry of the C8 substituents was obtained in both molecules. Ethyl substituent at the C6 position of 223A was obtained with correct stereochemistry through asymmetric alkylation/epimerization sequences of the tricyclic lactone. Cleavage of the excess carbon on the C5 position of all three indolizidines was performed by using a Barton decarboxylation protocol. Reduction of the corresponding indolizidin-3-ones by LAH completed the total synthesis of (–)-167B, (–)-209I and (–)-223A.

Mg/Al dissimilar materials were welded successfully by GTAW with SAlMg-1 and SAlMg-2 welding wire of Mg-Al system. The nice weld shape and free defects of joints are obtained. The test results indicated that continuous lamellar intermetallic compounds is not found The structure of Mg side in the fusion zone is composed of α-Mg solid solution+ β-Al12Mg17eutectic structure and precipitates β-A112lMg17on the grain boundary. The structure in the weld zone is mainly α-Mg solid solution + β-A112lMg17solid solutions. Mg and Al content are stable in the fusion zone of Mg side. However, in the weld zone of Mg side the Mg content is decreased gradually, and the Al content is increased that reaches a stable level in the weld zone of Al side. As a result, when Mg content in the wire can hold a proper level, the intermetallic compounds will be controlled effectively, and the performance of AZ31/7005 welding joint can be improved.

The main purpose of this article is to propose a linear model-based approach for improving the tracking performance of linear motors. In particular, P- and PI-controllers, augmented with a linear-model-based feedforward controller and disturbance observer (DOB), were utilized in this research. Experimental results show that the feedforward controller can substantially reduce the phase-delay problem resulting from the limitation of closed-loop bandwidth. In addition, the DOB can reject nonlinear behaviors to keep a motor-system close to our nominal linear model. Compared with the results of using P- and PI-controllers only, tracking errors were reduced from 4.44% to 0.67% of the desired trajectory. Therefore, the proposed method provides a solution for improving the tracking performance of linear motors.

Highly functionalized chiral furo-pyrrolizidinones containing contiguous quaternary centers were synthesized in moderate to good yields by treatment of various hexahydro-3,4-dioxa-8a-aza-as-indacen-2-ones with m-CPBA under basic conditions through a tandem Cope elimination/1,3-dipolar cycloaddition reaction sequence, followed by N-O cleavage and lactam ring cyclization.

This paper describes a convenient and efficient method for synthesizing chiral alcohol-substituted vinylogous urethanes, in which the double bond has E configuration was determined by single crystal X-ray analysis. In addition, we investigated the anti-aldol reactions of these chiral vinylogous urethane anions. The use of (1S,2R,4R)-1-(hydroxydiphenylmethyl)-7,7-dimethylbicyclo[2,2,1]-heptan-2-ol as a chiral auxiliary, provided the best enantioselectivities, and the resulting vinylogous urethane lactone could be used for the synthesis of (−)-prelactone B. A plausible mechanism for the generation of major enantiomeric isomer was discussed.

A new briarane-type diterpenoid, briaviolide Q (1), along with a known analogue, excavatolide Z (2), were obtained from a cultured octocoral Briareum violaceum. Details of the isolation and structure determination of briarane 1 from spectroscopic data are presented in this paper. In RAW264.7 cells, a macrophage-like murine cell line, briarane 1 was found to inhibit the protein expression of pro-inflammatory inducible nitric oxide synthase (iNOS) in cells stimulated by lipopolysaccharide (LPS).

The asymmetric [2,3]-Wittig rearrangement of the dienolates of various chiral β-pyrrolidinyl-γ-allyloxyl-α,β-unsaturated esters was investigated using different chiral secondary alcohol substitutions. When (1S,2R,4R)-2-hydroxy-7,7-dimethylbicyclo[2,2,1]heptane-1-carboxylic acid diisopropylamide was used as chiral auxiliary, it provided the best enantioselectivity in the rearrangement. When various γ-allyloxy substitutions underwent temperature and additive studies, 1,1-dimethylpropenoxy substitution was found to give the best enantioselectivity. The methodology was applied to the total synthesis of (+)-eldanolide.

Detection and surveillance of food commodities containing cyanide is a crucial issue of food safety. In this study, five strains of Pleurotus eryngii (P. eryngii) were grown in submerged culture of yeast malt broth (YMB) with the suspected production of HCN. A safety-warranted U-bent glass distilling collector with three enlarged bulbs on each arm was designed to recover the broth vapor. When AgNO(3) solution was used as an absorbent to interact with the vapor, a white precipitate was formed. The precipitate was isolated and identified as AgCN by FT-Raman spectroscopic analysis. When the absorbent was substituted by KOH, after evaporation to dryness, dissolved in D(2)O, and followed by (13)C-NMR analysis, a KCN spectrum was achieved. Formation of AgCN and KCN confirmed HCN production in the broth by P. eryngii. When a sodium picrate solution (1.4%) was used as an absorbent and various authentic KCN solutions were applied for distillation and followed by absorbance determination at 510 nm, a linear dose-dependent relationship was obtained and the procedure was applied for HCN quantification of the marketed P. eryngii mushrooms (fruiting body). As estimated, 67.3% of the products contained HCN less than 1.0 mg/kg, 17.3% between 1.0 and 2.0 mg/kg, and 15.4% higher than 2.0 mg/kg. When the mushrooms were sliced and cooked in water at 95 degrees C for 6 min, 89.1% of the original HCN was lost. When the P. eryngii strains were respectively grown by submerged cultivation in YMB or YMB supplemented with 2.5% glycine for 16 days, HCN content was slightly higher in the latter than in the former for each strain.

Dienolates of various γ-allyloxy substituted methyl β-pyrrolidinyl (E)-2-butenoate undergo a [2,3]-Wittig rearrangement to generate various 5-alkenyl-4-pyrrolidin-1-yl-5H-furan-2-one type compounds.

Zn-Al hydrotalcites were prepared by coprecipitation method with the Zn/Al molar ratio of 3:1, 2:1 and 1:1. Sodium dodecyl sulfate (SDS) and 2-carboxyethyl phenyl phosphinic acid (CEPPA) were adopted to modify hydrotalcite by coprecipitation method. The structure of Zn-Al hydrotalcites and the modified ones were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR) and scanning electron microscopy (SEM) coupled with energy dispersive spectrometer (EDS). XRD results indicated that the layered structure of Zn-Al hydrotalcites was influenced by the Zn/Al molar ratio. The Absorption peaks of Organic groups were observed in FT-IR Spectroscopy of SDS-LDH and CEPPA-LDH, which proved successfully synthesis of SDS modified LDH and CEPPA modified LDH. The SEM and EDS results confirmed the existence of SDS and CEPPA in the modified products, which are consistent with FT-IR results. The successful intercalation of SDS and CEPPA increased the interlayer space of LDH, which makes modified LDH promising and preferable as flame retardants in nanocomposites.

Parents are important stakeholders when demanding quality child care services, and it is necessary to take parents’ perspectives on child care quality seriously. The purpose of this study was to investigate Taiwanese parents’ perceptions regarding the importance of quality, and satisfaction with preschools based on participants’ demographic characteristics, child’s ages, and types of schools. Convenience sampling was utilized in this study. Data were collected from 810 participants with at least one three- to five-year-old child enrolled in one of 20 preschools in Taiwan. The instrument identified parental perceptions of quality and satisfaction with child care programs were categorized into seven domains: Program Characteristics, Teacher Characteristics, Interactions, Curriculum, Safety and Health, Physical Environment, and Evaluation. Health and safety issues tended to be more important in determining parental ratings for quality and satisfaction when children were enrolled preschool programs. There were no significant differences on parental ratings of the importance of quality among parental demographic characteristics and child’s ages, and only significant difference by children’s types of schools. Overall, results showed parents were satisfied with their current preschool programs. The findings have implications for parents, practitioners, and policy makers; for example, parents’ education; Parent-Teacher partnerships; and effective communication for teacher-parent interactions. Recommendations for future research were addressed.

We investigate the operation of a new device featuring a side-gate scheme and suspended poly-Si nanowire (NW) channels. The fabrication adopted a sidewall-spacer-etching technique to form the poly-Si NW channels. The NW channels were further suspended using a simple wet-etching step. An interesting hysteresis phenomenon is observed in the I-V characteristics. In addition, a steep subthreshold swing (< 60 mV/dec) is also observed in the transfer curves. A scenario is proposed to explain the operation of such a device.

Birch reduction and reduction-alkylations of 4 provide 3-methyl-8-phenyl-3,4,5,6,7,8-hexahydroisocoumarin 6 (88% yield) and a series of 8a-substituted-3-methyl-8-phenyl-3,4,6,7,8,8a-hexahydroisocoumarins 5a-d (84–89%). Conversions of 5a and 6 to cyclohexenones 12 and 13, and 6 to butadiene carboxylic acid 14 also are described.

A new polyoxygenated briarane diterpenoid, briarenol B (1), was isolated from the octocoral Briareum excavatum and its structure determined from spectroscopic data. In RAW264.7 cells, a macrophage-like murine cell line, briarane B (1) was found to enhance the protein expression of pro-inflammatory cyclooxygenase (COX-2) and inducible nitric oxide synthase (iNOS) in cells stimulated by lipopolysaccharide (LPS).

This paper presents a numerical model based on a multimode characteristics method for fully coupled simulation of water and sediment movement in mobile-bed alluvial channels with nonuniform bed materials. Along with the characteristics, the temporal evolutions of flow depth and velocity, bed elevation, and bed-material composition of a well-defined river reach with proper boundary conditions can be simultaneously determined. From the results of the test runs, the proposed model provides useful information about the interactions among disturbance waves of different orders of magnitude and their influence on the formation of flow field, bed topography, and bed-material composition. Such information cannot be easily obtained from finite-difference methods.

Di-isononyl phthalate esters (DINPs) are endocrine-disrupting chemicals and have replaced di(2-ethylhexyl) phthalate (DEHP) as the major plasticizer for poly(vinyl chloride) (PVC) products in recent years. Exposure marker discovery of DINPs is crucial, because of their high potential for human exposure and toxicity. Here, we propose an alternative approach for tracing signals derived from stable isotope-labeled precursors with varied labeling ratios to efficiently filter probable metabolite signals. The statistical process, which involves a signal mining algorithm with isotope tracing (SMAIT), has effectively filtered 13 probable DINP metabolite signals out of the 8867 peaks in the LC-MS data obtained from incubated stable isotope-labeled precursors with liver enzymes. Seven of the 13 probable metabolite signals were confirmed as DINP structure-related metabolites by preliminary MS/MS analyses. These 7 structure-related metabolite signals were validated as effective DINP exposure markers, using urine samples collected from DINP-administered rats without time-consuming comprehensive structure identification. We propose that the 7 identified possible DINP metabolite signals of m/z 279.1, 293.1, 305.1, 307.1, 321.1, 365.1, and 375.1 are potential markers for DINP exposure and should be investigated further. The integrated approach described here can efficiently, and systematically, filter probable metabolite signals from a complex LC-MS dataset for toxic exposure marker discovery. It is a relatively low-cost/rapid workflow for exposure marker discovery.

The highly functionalized title compounds (III) containing contiguous quarternary centers are synthesized by oxidation of the tricyclic compounds (I) with MCPBA under basic conditions through a tandem Cope elimination/1,3-dipolar cycloaddition sequence followed by reduction of (II) inducing N—O cleavage and lactam ring cyclization.

Four-step synthesis of achiral and chiral 4-(1-pyrrolidinyl)-2(5 H )-thiophenones with 61 and 66% overall yields are described. The γ-alkylation reaction studies and synthetic applications toward the thiolactomycin analog are also reported.

Birch reduction and reduction-alkylations of 4 provide 3-methyl-8-phenyl-3,4,5,6,7,8-hexahydroisocoumarin 6 (88% yield) and a series of 8a-substituted-3-methyl-8-phenyl-3,4,6,7,8,8a-hexahydroisocoumarins 5a-d (84–89%). Conversions of 5a and 6 to cyclohexenones 12 and 13, and 6 to butadiene carboxylic acid 14 also are described.

A three-step conversion of (±)-mellein (1) to (±)-ramulosin (6) in 41% overall yield is described. A synthesis of the spruce budworm toxin 7 also is reported.

Four-step synthesis of achiral and chiral 4-(1-pyrrolidinyl)-2(5 H )-thiophenones with 61 and 66% overall yields are described. The γ-alkylation reaction studies and synthetic applications toward the thiolactomycin analog are also reported.

Vinylogous urethanes derived from condensation of prolinol or prolinol tert-butyldimethylsilyl ether with 4-allyloxyketoester were found to undergo a thermal [3,3]-sigmatropic rearrangement, providing compounds with N-substituted quaternary carbon centers. Cyclizations (subsequently or in situ) of the rearranged products generated hexahydro-3,4-dioxa-8a-aza-as-indacen-2-ones. Various terminally substituted allyloxy ketoesters and arylmethoxy ketoesters were found to generate tricyclic compounds via [1,3]-sigmatropic rearrangement. Finally, tricyclic lactones were transformed successfully into lactams.

An electrospray ionization tandem mass spectrometry (ESI-MS/MS) system with an online dual-loop cleanup device was developed for simultaneous quantitation of the urinary benzene exposure biomarkers trans,trans-muconic acid (ttMA) and S-phenylmercapturic acid (SPMA). The cleanup device was constructed from an autosampler, two electrically operated two-position switching valves, a reversed-phase C18 trap cartridge, a 200-μL loop, and two solvent-delivery pumps. The device was interfaced directly with a triple-quadrupole mass spectrometer and fully controlled by computer software and hardware. Because isotope dilution by introducing 13C-labeled ttMA and SPMA as internal standards was employed, the precision of the analytical system was high (for ttMA, intra- and inter-day CV values ranged from 3.82–4.53%; for SPMA, 2.13–7.06%). The calibration curves obtained using human urine spiked with ttMA were linear from 15.6–4000 μg/L (R = 0.9998) and SPMA at concentrations from 0.78–200 μg/L (R = 0.9993). The method detection limit (MDL) for SPMA was 0.23 μg/L. The MDL of ttMA could not be determined accurately because of unavailability of an appropriate blank urine matrix, but was estimated to be lower than 7.43 μg/L. Without tedious manual sample cleanup procedures the analytical system is fully automated and is therefore useful for high-throughput simultaneous determination of urinary ttMA and SPMA. The sample throughput is roughly 100 samples per day. With the selectivity and the sensitivity provided by MS/MS detection, the analytical system can be used for large-scale monitoring of environmental or occupational exposure of humans to benzene. Copyright © 2004 John Wiley & Sons, Ltd.

We experimentally demonstrate very efficient non-phase-matched second- and third-harmonic generation from a macroporous GaP. The generated second-harmonic signal is independent of crystallographic orientation, and its enhancement is believed to be due to the light localization for which conditions exist in the studied samples of porous GaP. The nonlinear optical results are correlated with linear optical scattering studies and atomic-force microscopic images of the studied surfaces.

A new algorithm for multi-target angle tracking is presented using the antenna array output. It combines the discrete wavelet transform (DWT) based beamspace processing with MUSIC algorithm to track multiple target angles by recursively updating the center frequency of the spatial prefilter. Compared to the method of Lo and Li (1992), the improved performance of the proposed method is demonstrated by computer simulations.

A concept of distributed actuators and their controls for ultra-fast, material transfer network based upon linear induction motors (LIMs) is presented in this paper. The distributed actuator consists of modularized stationary primaries connected to form a distributed, closed guideway structure with multiple loops through which vehicles (moving secondaries of the LIM) are propelled at a maximum velocity of 120 km/hr and a maximum acceleration of 4 g. The turning radius can be less than 1 m. A transverse flux LIM propulsion unit design provides robust, direct-drive electromagnetic vector controlled propulsion and electromagnetic steering. The controlled moving secondary vehicles are completely passive with no power, sensing, or control intelligence onboard. The need to control multiple passive vehicles simultaneously moving through a multitude of propulsion units mandates a highly distributed control architecture where propulsion units cooperate using a communication network. The need for centralized database and control is eliminated by endowing the communication network with a topology identical to that of the guideway network. The distributed control architecture ensures spontaneity of material delivery by integrating vehicle motion control with intelligence for real-time collision avoidance, a parallel shortest-path routing algorithm, and an autonomous dispatching protocol. Recent experimental results are presented.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Background The gene expression is usually described in the literature as a transcription factor X that regulates the target gene Y. Previously, some studies discovered gene regulations by using information from the biomedical literature and most of them require effort of human annotators to build the training dataset. Moreover, the large amount of textual knowledge recorded in the biomedical literature grows very rapidly, and the creation of manual patterns from literatures becomes more difficult. There is an increasing need to automate the process of establishing patterns. Methodology/Principal Findings In this article, we describe an unsupervised pattern generation method called AutoPat. It is a gene expression mining system that can generate unsupervised patterns automatically from a given set of seed patterns. The high scalability and low maintenance cost of the unsupervised patterns could help our system to extract gene expression from PubMed abstracts more precisely and effectively. Conclusions/Significance Experiments on several regulators show reasonable precision and recall rates which validate AutoPat's practical applicability. The conducted regulation networks could also be built precisely and effectively. The system in this study is available at http://ikmbio.csie.ncku.edu.tw/AutoPat/.

A three-step conversion of (±)-mellein (1) to (±)-ramulosin (6) in 41% overall yield is described. A synthesis of the spruce budworm toxin 7 also is reported.

A direct acting free piston internal combustion engine/hydrostatic pump is analyzed. This device would take the place of a conventional engine-driven hydrostatic pump, and would be expected to offer significant advantages in cost, weight, and efficiency. The free piston configuration eliminates the need for a crankshaft-connecting rod system, and the comparable mechanism of the pump that converts rotary to reciprocating motion. Analysis of the design was done by computer simulation using a thermodynamic model of the combustion cylinder in combination with the system dynamics