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Marker-free, genetically-modified rice was created by the tissue-specifically regulated Cre/loxP system, in which the Cre recombinase gene and hygromycin phosphotransferase gene (hpt) were flanked by two directly oriented loxP sites. Cre expression was activated by the tissue-specific promoter OsMADS45 in flower or napin in seed, resulting in simultaneous(More)
In order to find new biorational pesticides, eight new 6-substituted ether derivatives of Celangulin-V were synthesized. The structures were confirmed by IR, 1H NMR and 13C NMR spectroscopic and HRMS analyses. The insecticidal activities of these compounds were tested against third-instar larvae of Mythimna separata. Four derivatives (b, c, f, g) showed(More)
In order to develop new biorational pesticides and clarify the potential structural factors needed for the biological activity of celangulin-V analogues, thirty novel nitrogenous derivatives were designed and synthesized. The single crystal structure of celangulin-V is reported for the first time and provides a more accurate structure than that previously(More)
Twelve new triazole derivatives of Phrymarolin were prepared from Phrymarolin I and the structures of all the derivatives were fully characterized by (1)H-NMR, (13)C-NMR and MS spectral data analyses. Larvicidal activities against 4rd instar larvae of Culex pipiens pallens of these Phrymarolin analogues were assayed. Although the triazole derivatives of(More)
The ionization/dissociation mechanism of cyclopentanone has been experimentally investigated in molecular beam by irradiating with intense 394 and 788 nm laser fields with pulse duration of 90 fs. The range of laser intensities varied from 3 x 10(13) to 4 x 10(14) W/cm(2). For both wavelengths, the singly charged parent ion is observable while the doubly(More)
A genetic algorithm was used to control the photoluminesce-nce (PL) from GaAs(100). A spatial light modulator (SLM) used feedback from the emission to optimize the spectral phase profile of an ultrashort laser pulse. Most of the experiments were performed using a sine phase function to optimize the integrated PL spectrum over a specified wavelength range,(More)
The mass spectra of a series of cycloketone molecules, cyclopentanone (CPO), cyclohexanone (CHO), cycloheptanone (CHPO), and cyclooctanone (COO) are measured in a 788 or 394 nm laser field with 90 fs pulse duration and the intensity ranging from 5 x 10(13) W/cm(2) to 2 x 10(14) W/cm(2). At 788 nm, a dominated parent ion peak and some weak peaks from the(More)
The discovery of novel leads and new mechanisms of action is of vital significance to the development of pesticides. To explore lead compounds for botanical insecticides, 77 β-dihydroagarofuran derivatives were designed and synthesized. Their structures were mainly confirmed by (1)H NMR, (13)C NMR, DEPT-135°, IR, MS, and HRMS. Their insecticidal activity(More)
BACKGROUND 1β, 2β, 4α, 6α, 8β, 9α, 12-hepthydroxyl-β-dihydroagarofuran is the main skeleton of β-dihydroagarofuran sesquiterpenoids, which exhibit excellent insecticidal activity. To study further the structure-activity relationship of β-dihydroagarofuran sesquiterpenoids towards finding novel botanical pesticides, two series of new structurally modified(More)
The holes were drilled by femtosecond laser pulse (800 nm, 100 fs) on Cu sheets at different ambient pressures. The pressure range was from 1 Pa to atmospheric pressure. The number of pulses to drill through the target, the stable photodiode signal, and the hole diameter were obtained as functions of ambient pressure. The morphology of the hole was observed(More)