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Aims To identify the roles of the two O-methyltransferase homologous genes pdmF and pdmT in the pradimicin biosynthetic gene cluster of Actinomadura hibisca P157-2. Methods and results Pradimicins are pentangular polyphenol antibiotics synthesized by bacterial type II polyketide synthases (PKSs) and tailoring enzymes. Pradimicins are naturally derivatized by combinatorial O-methylation at two positions (i.e., 7-OH and 11-OH) of the benzo[α]naphthacenequinone structure. PdmF and PdmT null mutants (PFKO and PTKO) were generated. PFKO produced the 11-O-demethyl shunt metabolites 11-O-demethylpradimicinone II (1), 11-O-demethyl-7-methoxypradimicinone II (2), 11-O-demethylpradimicinone I (3) and 11-O-demethylpradimicin A (4), while PTKO generated the 7-O-demethyl derivatives pradimicinone II (5) and 7-hydroxypradimicin A (6). Pradimicinones 1, 2, 3, and 5 were fed to a heterologous host Escherichia coli harbouring expression plasmid pET-22b::pdmF or pET-28a::pdmT. PdmF catalysed 11-O-methylation of pradimicinones 1, 2, and 3 regardless of O-methylation at the C-7 position, while PdmT was unable to catalyse 7-O-methylation when the C-11 hydroxyl group was methylated (5). Conclusions PdmF and PdmT were involved in 11-O- and 7-O-methylations of the benzo[α]naphthacenequinone moiety of pradimicin, respectively. Methylation of the C-7 hydroxyl group precedes methylation of the C-11 hydroxyl group in pradimicin biosynthesis. Significance and impact of the study This is the first reported demonstration of the functions of PdmF and PdmT for regiospecific O-methylation, which contributes to better understanding of the post-PKS modifications in pradimicin biosynthesis as well as to rational engineering of the pradimicin biosynthetic machinery.

In unmanned vehicles` navigation, the shapes of obstacles are generally irregular and complex. The motion of vehicles based on the range sensor system such as ultrasonic sensors or laser sensors can be unstable due to the irregular shape of the obstacles. In this case, to generate stable trajectory of unmanned vehicles equipped with range sensors, we need an approach that can simplify an obstacle`s irregular shape information. In this paper, we propose the trajectory generation algorithm that an vehicle can stably navigate in the environments where irregular shaped obstacles are scattered. The proposed method is verified through the analysis of vehicle`s trail and direction data acquired by simulations and implementations.

Aims: To characterize antifungal principles from the methanol extract of Magnolia obovata and to evaluate their antifungal activities against various plant pathogenic fungi. Methods and Results: Four neolignans were isolated from stem bark of M. obovata as antifungal principles and identified as magnolol, honokiol, 4-methoxyhonokiol and obovatol. In mycelial growth inhibition assay, both magnolol and honokiol displayed more potent antifungal activity than 4-methoxyhonokiol and obovatol. Both magnolol and honokiol showed similar in vivo antifungal spectrum against seven plant diseases tested; both compounds effectively suppressed the development of rice blast, tomato late blight, wheat leaf rust and red pepper anthracnose. 4-Methoxyhonokiol and obovatol were highly active to only rice blast and wheat leaf rust respectively. Conclusions: The extract of M. obovata and four neolignans had potent in vivo antifungal activities against plant pathogenic fungi. Significance and Impact of the Study: Neolignans from Magnolia spp. can be used and suggested as a novel antifungal lead compound for the development of new fungicide and directly as a natural fungicide for the control of plant diseases such as rice blast and wheat leaf rust.

This experiment was carried out to classify heading date of forage rye cultivars, and study agronomic characteristics, dry matter yield per ha and forage quality of winter rye cultivars in Suwon for 2 year from 2002 to 2003. The earliest cultivars among forage winter rye cultivars were Olhomil and Vitagrazer, which the heading date was April 21. The latest cultivar was Danko, which was May 5. Koolgrazer was April 26 and Homil 22 was April 30, respectively. Therefore, we classified the cultivars into three groups according to their heading date. The earliest group includes Olhomil, Vitagrazer, Paldanghomil, the middle group includes 5 cultivars which are Koolgrazer, Barrgazer, Maton, Wintergrazer and Homil22, and the latest group contains Humbolt and Danko. The number of tiller per of most cultivars were more than 1,000. The cultivar which has lowest tiller was Humbolt, which dry matter yield was the largest, and its tiller was 789. The lodging happened after each precipitation. Danko was the cultivar that has lowest lodging frequency. There has been little disease and insect and the difference in the quality of each cultivar. The yield of dry matters per ha of Humbolt was increased , Vita grazer , Maton comparing the standard cultivar, Kool grazer of 12,409kg, and Homil 22 was almost the same with the standard cultivar.

This study was carried out to select the promising forage crops for forage production in paddy field of NLRI, RDA, Suwon from 1999 to 2001. The species of forage crop used in this experiment were barley(3 varieties), wheat(2), rye(3) and Italian ryegrass(IRG, 3). Stages of heading, milk and yellow ripe of barley were 1 May, middle May and late May, respectively. In milk to yellow ripe stage, dry matter(DM) and total digestible nutrient(TDN) yield of barley were MT and MT per ha, and Albori was the most promising variety among the barley. The growth of wheat was a little late compared to that of barley. but it seemed to be crop having higher forage yield and nutritive value. In milk to yellow stage, DM and TDN yield of wheat were MT and MT per ha. Heading stage of rye was 27 to 29 April, and it seemed to be suitable for harvest at heading to flowering stage because of heavy lodging after flowering. In flowering stage, DM and TDN yield of rye were 10.18 and 6.03 MT per ha. Heading stage of early maturing IRG was 7 May and it seemed to be good for harvest at flowering stage of middle May in cropping system. In flowering stage, DM and TDN yield of early type IRG were 4.48 and 2.96 MT per ha. The results demonstrated that the promising forage crops for forage production in paddy. field were rye and barley(Albori) in Middle region, and rye harvesting at early May was recommended when considered middle May of rice transplanting period, and rye and barley considered late May of rice planting period. Also early maturing and high yielding IRG variety was strongly needed.

Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum L. pratensis and intergeneric hybrids of Lolium Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12 of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

“DK 537”has been selected by forage crop breeding team at the National Livestock Research Institute(NLRI), RDA and has been determined by the Deliberative Council of the National Agricultural Cooperative Federation(NACF) in 2002, as a new recommended hybrid which is early maturing, good quality and hi호 yield of corn for silage. The characteristics of this hybrid are as follows ; 1. The seed coat is yellow and the mean of tasseling date is 5th of July, included in early maturing hybrid which is one day delayed than check cultivar, DK 501. The culm length is 246cm. It is resistant to lodging because of its low height from surface to ear. 2. DK 537 shows resistance to H. maydis and Maize Black-Streaked Dwarf Virus(MBSDV). It also shows strength to corn borer as much as DK 501 does. 3. Fresh yield. dry matter yield. and TDN per a ha are 50 tons, 16.9 tons, and 11.4 tons respectively. which are almost same yielding level of DK 501. Its percent ear to total dry matter is 50.8% at the same time. Through all these tests, we could make sure at DK 537 hybrid will be recommended as good forage crop.

Plasma enhanced chemical vapor deposition of the Cu films on Si substrate was investigated in which 30 A Cu-seed layer on the substrate was formed by partially ionized beam prior to deposition. In order to elucidate the difference in growth mechanism of Cu film between on Cu-seed layer and on bare Si, the initial stage of Cu-seed layer grown by partially ionized beam was studied by transmission electron microscopy and different nucleation formation processes from conventional method was shown. A high deposition rate and an improved adhesion strength were achieved when thick Cu film on the Cu seeded Si substrate was deposited by plasma enhanced chemical vapor deposition.

Aims: To characterize the volatile antifungal compound produced by Oxyporus latemarginatus EF069 and to examine in vitro and in vivo fumigation activity of the fungus. Methods and Results: An antifungal volatile-producing strain, O. latemarginatus EF069 inhibited the mycelial growth of Alternaria alternata, Botrytis cinerea, Colletotrichum gloeosporioides, Fusarium oxysporum f. sp. lycopersici, and Rhizoctonia solani by mycofumigation. An antifungal volatile compound was isolated from the hexane extract of wheat bran–rice hull cultures of O. latemarginatus EF069 by repeated silica gel column chromatography and identified as 5-pentyl-2-furaldehyde (PTF). The purified PTF inhibited mycelial growth of R. solani in a dose-dependent manner. The mycofumigation with solid cultures of EF069 also reduced effectively the development of postharvest apple decay caused by B. cinerea and Rhizoctonia root rot of moth orchid caused by R. solani. Conclusions: Oxyporus latemarginatus EF069 showed in vitro and in vivo fumigation activity against plant pathogenic fungi by producing 5-pentyl-2-furaldehyde. Significance and Impact of the Study: Oxyporus latemarginatus EF069 producing an antifungal volatile compound may be used as a biofumigant for the control of fungal plant diseases.

Aims: To isolate and identify antioomycete substances from Fusarium oxysporum EF119 against Phytophthora infestans and to investigate their antimicrobial activities against various plant pathogenic bacteria, oomycetes and true fungi. Methods and Results: Two antioomycete substances were isolated from liquid cultures of F. oxysporum EF119, which shows a potent disease control efficacy against tomato late blight caused by P. infestans. They were identified as bikaverin and fusaric acid by mass and nuclear magnetic resonance spectral analyses. They inhibited the mycelial growth of plant pathogenic oomycetes and fungi. Fusaric acid also effectively suppressed the cell growth of various plant pathogenic bacteria, but bikaverin was virtually inactive. Treatment with bikaverin at 300 μg ml−1 suppressed the development of tomato late blight by 71%. Fusaric acid provided effective control against tomato late blight and wheat leaf rust over 67% at concentrations more than 100 μg ml−1. Conclusions: Both bikaverin and fusaric acid showed in vitro and in vivo antioomycete activity against P. infestans. Significance and Impact of the Study: Fusarium oxysporum EF119 producing both bikaverin and fusaric acid may be used as a biocontrol agent against tomato late blight caused by P. infestans.

We extend the theory of shear suppression of turbulence in the toroidal geometry (1995 Phys. Plasmas 2 1648) by considering initially tilted turbulence eddies which are routinely observed in nonlinear simulations of tokamak turbulence. Using the two point nonlinear decorrelation theory, we obtain a new shear suppression criterion which depends on the relative sign of shear and initial tilting angle. Our result implies a different level of turbulent transport depending on this relative sign.

We present a new analytic expression for turbulent equipartition (TEP) pinch of toroidal angular momentum originating from magnetic field inhomogeneity of spherical torus (ST) plasmas. Starting from a conservative modern nonlinear gyrokinetic equation (Hahm et al 1988 Phys. Fluids 31 2670), we derive an expression for pinch to momentum diffusivity ratio without using a usual tokamak approximation of B???1/R which has been previously employed for TEP momentum pinch derivation in tokamaks (Hahm et al 2007 Phys. Plasmas 14 072302). Our new formula is evaluated for model equilibria of National Spherical Torus eXperiment (NSTX) (Ono et al 2001 Nucl. Fusion 41 1435) and Versatile Experiment Spherical Torus (VEST) (Chung et al 2013 Plasma Sci. Technol. 15 244) plasmas. Our result predicts stronger inward pinch for both cases, as compared to the prediction based on the tokamak formula.

This paper presents a real-time vehicle dynamic analysis method using suspension composite joints. Typical suspension systems of vehicles such as MacPherson strut, double wishbone, trailing arm and solid axle suspension systems are modelled by suspension composite joints. The joints are derived and utilised to reduce the computation time of simulation without any degradation of kinematical accuracy of the suspension systems. They are modelled using massless links on the suspension members that have small masses but have kinematical importance. Using the developed suspension composite joints, a multibody vehicle dynamic model is formed and simulations are performed. Accuracy of the simulation results is compared to the real vehicle field test results as well as to the simulation results with a full multibody vehicle model. It is found that the simulation results using the proposed method are very accurate and real-time simulation is achieved on a computer with single PowerPC 604 processor.