Adventitious shoot regeneration from in vitro stem explants of Phellodendron amurense

An efficient in vitro plant regeneration system from stem explants was established in Phellodendron amurense. Factors influencing shoot regeneration from stems including culture medium type, combinations of plant growth regulators and carbon source in the medium were investigated. Adventitious shoot regeneration was significantly influenced by the type of medium. Murashige and Skoog medium (MS) was the best for promoting shoot regeneration, followed by Gamborg medium (B5) and woody plant medium (WPM). The combination of 6-benzyladenine (BA) and naphthaleneacetic acid (NAA) produced better results for shoot regeneration. The optimum shoot regeneration frequency (74.5%) and number of shoots per explant (12.3) was achieved using MS medium supplemented with 29.7 M BA and 5.8 M NAA. High concentrations of BA and NAA in the medium inhibited shoot formation. Among the three sugars tested, 20 g dm-3 glucose was the optimum for shoot regeneration. Rooting of regenerated shoots was successful on 1/4-strength MS medium with the addition of 15.4 M IBA. Almost 100% plantlets survived acclimatization after transferred to soil.Key words: Phellodendron amurense, callus, shoot regeneration, stem explants

Growth mode and strain evolution during InN growth on GaN(0001) by molecular-beam epitaxy

The plasma-assisted molecular-beam epitaxy technique was used to study the epitaxial growth of InN on GaN. A relationship between film growth mode and the deposition condition was established by combining reflection high-energy electron diffraction (RHEED) and scanning tunneling microscopy (STM). The sustained RHEED intensity oscillations were recorded for 2D growth while 2D nucleation islands were revealed by STM. Results showed less than three oscillation periods for 3 D growth, indicating the Strnski-Krastanov (SK) growth mode of the film.published_or_final_versio

Modeling the stress dependence of magnetic hysteresis based on Stoner-Wohlfarth theory

© 2015 IEEE. This paper presents an improved approach for simulating magnetic hysteresis, which takes into account the effect of applied stress, based on an extended Stoner-Wohlfarth (S-W) model. Meanwhile, the S-W asteroid rotates and shrinks, and the stable direction of magnetization of the particle can be calculated from the new energy minimum conditions. This developed model is applied to analyze the magnetic hysteresis phenomenon of a soft magnetic composite (SMC) material under different compaction process, and the results of simulations are in good quantitative agreement with experimental data

Two-dimensional elemental operator for modeling the vectorial hysteresis of soft magnetic composite material

© 2015 IEEE. This paper presents a two-dimensional elemental operator with biaxial anisotropy based on the physical mechanisms of the cubic textured magnetic materials, and deduces an analytical expression of the direct relationship between magnetic field strength H and magnetization M for a single elemental operator by the partial approximate substitutions. To verify the proposed model, the magnetic hysteresis of a soft magnetic composite material SOMALOYTM 500 under alternating excitations was simulated and compared with the experimental results obtained by a 3D magnetic property tester. The results suggest that the proposed approach can be a useful tool in the modeling of vectorial magnetic hysteresis and the calculation of iron loss in practical engineering electromagnetic field analysis

Wavelength tunable and amplitude-equilibrium dual-wavelength lasing sources with dual-pass Raman/Brillouin amplification configuration

2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Androgen receptor acetylation governs trans activation and MEKK1-induced apoptosis without affecting in vitro sumoylation and trans-repression function

This work was supported by grants from the NIH (R01CA86072 to R.G.P. and R01CA72038-01 to S.A.W.F.) and The Susan Komen Breast Cancer Foundation (to R.G.P.). R.T.H. and E.J. were supported by the Medical Research Council. Y.-G.Y. is supported by grant CA26504 to E. R. Stanley. Work conducted at the Albert Einstein College of Medicine was supported by Cancer Center Core National Institutes of Health grant 5-P30-CA13330-26.The androgen receptor (AR) is a nuclear hormone receptor superfamily member that conveys both traits repression and ligand-dependent trans-activation function. Activation of the AR by dihydrotestosterone (DHT) regulates diverse physiological functions including secondary sexual differentiation in the male and the induction of apoptosis by the JNK kinase, MEKK1. The AR is posttranslationally modified on lysine residues by acetylation and sumoylation. The histone acetylases p300 and P/CAF directly acetylate the AR in vitro at a conserved KLKK motif. To determine the functional properties governed by AR acetylation, point mutations of the KLKK motif that abrogated acetylation were engineered and examined in vitro and in vivo. The AR acetylation site point mutants showed wild-type trans repression of NF-kappaS, AP-1, and Sp1 activity; wild-type sumoylation in vitro; wild-type ligand binding; and ligand-induced conformational changes. However, acetylation-deficient AR mutants were selectively defective in DHT-induced trans activation of androgen-responsive reporter genes and coactivation by SRC1, Ubc9, TIP60, and p300. The AR acetylation site mutant showed 10-fold increased binding of the N-CoR corepressor compared with the AR wild type in the presence of ligand. Furthermore, histone deacetylase 1 (HDAC1) bound the AR both in vivo and in cultured cells and HDAC1 binding to the AR was disengaged in a DHT-dependent manner. MEKK1 induced AR-dependent apoptosis in prostate cancer cells. The AR acetylation mutant was defective in MEKK1-induced apoptosis, suggesting that the conserved AR acetylation site contributes to a pathway governing prostate cancer cellular survival. As AR lysine residue mutations that abrogate acetylation correlate with enhanced binding of the N-CoR repressor in cultured cells, the conserved AR motif may directly or indirectly regulate ligand-dependent corepressor disengagement and, thereby, ligand-dependent trans activation.Publisher PDFPeer reviewe

Geochemical Constrains on Nature of Source Region of The Late Permian Emeishan Continental Flood Basalts, SW China

Abstract in http://www.lpi.usra.edu/meetings/gold2001/pdf/3488.pd

Promotion of ganoderic acid production in Ganoderma sinense by the addtion of an ether extract from Eupolyphaga sinensis, a medicinal insect

To screen stimulators from Chinese medicinal insects for mycelial growth and ganoderic acid (GA) production by Ganoderma sinense, the fungus was inoculated into the media with and without supplementation of a medicinal insect extract. The results show that all the water and ether extracts from the medicinal insects had no significant stimulatory effect on the biomass production (P > 0.05), and the extracts of Hydrotrechus remigator and Mylabris phalerata significantly inhibited the mycelial growth. However, the ether extract of Eupolyphaga sinensis at a concentration of 60 mgL-1 led to a significant increase in GA concentration from 187.6 ± 8.32 to 251.3 ± 11.27 mgL-1 (P < 0.01). Analysis of fermentation kinetics of G. sinense suggests that glucose concentration in the E. sinensis extract treatment group decreased more quickly as compared to the control group in the last 4 days of fermentation process, while the GA biosynthesis was promoted at the same period. However, the culture pH profile was not affected by the addition of the ether extract of E. sinensis.Key words: Medicinal fungus, Ganoderma sinense, submerged fermentation, Eupolyphaga sinensis, ganoderic acid

Isolation and Characterization of Batatasin III and 3,4’- Dihydroxy-5-methoxybibenzyl: A Pair of Positional Isomers from Sunipia scariosa

Purpose: To isolate and characterize chemical compounds of biological importance from the whole plant of Sunipia scariosa.Methods: The whole plant of Sunipia scariosa was extracted with methanol (MeOH) and chromatographed on silica gel and sephadex LH-20 to afford the pure isolates. High perfomance liquild chromatography (HPLC) was used for further purification of the isolated compounds. Characterization ofthe isolated compounds was achieved by 1H and 13C nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS).Results: Batatasin III (3,3’-dihydroxy-5-methoxybibenzyl) and  3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers, were isolated from the whole plant of Sunipia scariosa. The yields of the two isomers were 60 and 40 %, respectively, from the mixture of two  compounds.Conclusion: Batatasin III and 3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers were successfully isolated from the whole plant of Sunipia scariosa for the first time.Keywords: Sunipia scariosa, Batatasin III, 3,4’-Dihydroxy-5-methoxybibenzyl, Isomer

A particle swarm optimization based memetic algorithm for dynamic optimization problems

Copyright @ Springer Science + Business Media B.V. 2010.Recently, there has been an increasing concern from the evolutionary computation community on dynamic optimization problems since many real-world optimization problems are dynamic. This paper investigates a particle swarm optimization (PSO) based memetic algorithm that hybridizes PSO with a local search technique for dynamic optimization problems. Within the framework of the proposed algorithm, a local version of PSO with a ring-shape topology structure is used as the global search operator and a fuzzy cognition local search method is proposed as the local search technique. In addition, a self-organized random immigrants scheme is extended into our proposed algorithm in order to further enhance its exploration capacity for new peaks in the search space. Experimental study over the moving peaks benchmark problem shows that the proposed PSO-based memetic algorithm is robust and adaptable in dynamic environments.This work was supported by the National Nature Science Foundation of China (NSFC) under Grant No. 70431003 and Grant No. 70671020, the National Innovation Research Community Science Foundation of China under Grant No. 60521003, the National Support Plan of China under Grant No. 2006BAH02A09 and the Ministry of Education, science, and Technology in Korea through the Second-Phase of Brain Korea 21 Project in 2009, the Engineering and Physical Sciences Research Council (EPSRC) of UK under Grant EP/E060722/01 and the Hong Kong Polytechnic University Research Grants under Grant G-YH60