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To isolate genes responsive to N-acetylchitooligosaccharide elicitor in suspension-cultured rice cells, we screened rice ESTs by DNA microarray analysis, and were able to identify novel elicitor-responsive genes. Sequencing analysis of three ESTs revealed that the up-regulated genes include a transcription factor, Myb, small G-protein, Rac, and calmodulin. The results indicated the genome-wide change of gene expression in response to N-acetylchitooligosaccharide elicitor.

Advances in thin film fabrication techniques have made metal multilayer diffracting optics an important new technology. In this paper we present the results of characterization measurements on a variety of state-of-the-art metal multilayer samples and we describe their possible use in several monochromator applications.

Measurements of the gamma rays excited by neutron inelastic scattering in B11, Na, Si, K, Sc, Zr, In, I, Ta, Au, Tl, and Pb206 have been carried out by use of the conventional ring scatterer geometry within a neutron energy range from 0.2 Mev to 3.5 Mev. The studies were used to obtain information on level structure, to determine cross sections for gamma-ray excitation, and to make a test of the predictions of inelastic scattering cross sections computed by a combination of the statistical and optical models. New levels and information on the decay schemes have been found in Zr, I, Au, and Pb206. Excitation functions in terms of absolute cross sections are presented for the prominent gamma rays in the spectra of all the elements studied except Sc and Tl. Studies of the gamma rays from Pb206 have given experimental verification of the level scheme for the low spin states calculated by True and Ford. Statistical model calculations are presented which give reasonably good agreement with the experiments on Pb206 provided the penetrabilities are calculated using parameters obtained from an analysis of elastic scattering data specifically for Pb206. The analysis shows that the imaginary part of the optical potential is abnormally low for Pb206 compared to that for neighboring nuclei at comparable energies. The agreement in magnitude and shape between the experimental and calculated excitation functions can be improved if the imaginary part of the potential is permitted to increase with neutron channel energy.

The first excited states of ${\mathrm{Ca}}^{40}$ and ${\mathrm{Zr}}^{90}$ are 0+ states which decay to the 0+ ground state primarily by the emission of internal pairs or conversion electrons. These states have been excited by neutron inelastic scattering and their decay times have been observed by detecting the 0.51-Mev annihilation gamma rays as a function of time. The experimental method utilized a pulsed neutron source and the standard ring geometry often used for inelastic scattering measurements. Proton excitation of ${\mathrm{Ca}}^{40}$ in a different geometry was also used. To measure the lifetimes, the pulse-height spectra from a NaI(Tl) scintillation counter were recorded as a function of the delay time after the exciting pulse, and the intensity of the annihilation radiation was obtained from the area under the photopeak at 0.51 Mev. Selection of the time delays was made with the aid of either a time-to-pulse-height converter or a fast coincidence circuit. Mean lives for the first excited states of ${\mathrm{Ca}}^{40}$ and ${\mathrm{Zr}}^{90}$ were found to be (3.4\ifmmode\pm\else\textpm\fi{}0.2)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ sec and (90\ifmmode\pm\else\textpm\fi{}6)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ sec, respectively. Corresponding values of the reduced matrix elements $\ensuremath{\rho}$ are 0.15 and 0.056.

The energy of the gamma-radiation produced when ${\mathrm{Be}}^{9}$ is bombarded by 2.6-Mev protons has been measured with a scintillation spectrometer and found to be 3.58\ifmmode\pm\else\textpm\fi{}0.04 Mev. A suggestion of Hushley that this gamma-ray is produced in the reaction ${\mathrm{Be}}^{9}$ ($p$,$\ensuremath{\alpha}\ensuremath{\gamma}$) ${\mathrm{Li}}^{6}$ was verified by observing coincidences between the gamma-rays and low energy alpha-particles. The excited state of ${\mathrm{Li}}^{6}$ which emits the gamma-rays probably has spin zero and even parity and is presumably the analog of the ground state of the isobaric nucleus, ${\mathrm{He}}^{6}$. The thick target yield and cross section at resonance were found to be 4.8\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ gamma-rays per proton and 0.11\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}24}$ ${\mathrm{cm}}^{2}$, respectively.

The mirror nuclei of tritium and helium-3 have been studied by the method of elastic electron scattering. Absolute cross sections have been measured for incident electron energies in the range 110-680 MeV at scattering angles lying between 40 and 135\ifmmode^\circ\else\textdegree\fi{} in this energy range. The data have been interpreted in a straightforward manner and form factors are given for the distributions of charge and magnetic moment in the two nuclei over a range of four-momentum transfer squared 1.0-8.0 ${\mathrm{F}}^{\ensuremath{-}2}$. Model-independent radii of the charge and magnetic-moment distributions are given and an attempt is made to deduce form factors describing the spatial distribution of the protons in tritium and helium-3.

A NaI scintillation counter has been used to observe gamma rays from neutron inelastic scattering in ${\mathrm{B}}^{10}$, C, N, O, F, Mg, Al, S, Ca, Fe, Ni, Cu, Ta, Pb, and Bi. In most cases these gamma rays can be fitted into known level schemes of the target nuclides; however, a few gamma rays require the existence of previously undetected levels. In addition, several gamma rays have been observed from ($n, {p}^{\ensuremath{'}}\ensuremath{\gamma}$) and ($n, {\ensuremath{\alpha}}^{\ensuremath{'}}\ensuremath{\gamma}$) reactions. The problems involved in measuring absolute cross sections for the production of gamma rays are considered in detail. The usefulness of neutron inelastic scattering in nuclear spectroscopy is illustrated in several cases.

The cross section for the excitation of the 2.3-Mev metastable state in the Zr/sup 90/(n,n)Zr/sup 90m/ reaction was measured from threshold to 5 Mev. An irradiated-count cycle was used in which a Zr sample was first bombarded by monoenergetic neutrons and then transferred by a pneumatic transport system to a shielded counting station where the 2.3-Mev gamma rays from the decay of the metastable state were measured. The half life of this state was found to be T/ sub 1/2/ = 0.801 450 deg C in a 0.005 sec. The excitation curve has a threshold at 2.3 Mev and increases monotonically to 300 mb at 5 Mev. In addition to the threshold rise there are also marked increases in cross section that begin at 2.75 and 1.4 Mev. These increases are due to states at these energies that cascade through the 2.3-Mev state. The state at 2.75 Mev is probably the hitherto missing 4- state of the (p/sub 1/2/g/sub 9/2/) configuration and it is essentially equal to the 3- state at 2.75 Mev that was observed in other reactions. (auth)

The cross section for excitation of the 0.72-Mev gamma ray in the B/sup 10/(n.n' gamma )B/sup 10/ reaction was measured from threshold to 5.2 Mev. Resonances were observed at 1.93, at 2.6 Mev. The angular distributions of the 0.110-Mev and 0.197-Mev gamma rays in the F/sup 19/(n,n' gamma )F/sup 19/ reaction and the 0.847-Mev gamma ray in the Fe/sup 56/(n.n' gamma )Fe/sup 56/ reaction were also measured ai 2.56 Mev. The first of these was isotropic. the last two showed anisotropies but were symmetrical about 90 deg . The angular distribution of the Fe/sup 56/ gamma ray agrees well in both shape and absolute magnitude with calculaiions based on the statistical model. (auth)

The capture radiation from ${\mathrm{C}}^{13}(p, \ensuremath{\gamma}){\mathrm{N}}^{14}$ has been investigated and found to show cascade transitions which involve bound levels in ${\mathrm{N}}^{14}$ at 2.31, 3.95, 5.09, 5.81, 6.26, and 6.44 Mev in addition to the resonance levels at 8.06, 8.62, 8.70, 8.90, 8.98, 9.17, and 9.49 Mev.

A sodium iodide scintillation spectrometer has been used to study the gamma radiation produced when ${\mathrm{B}}^{10}$ is bombarded by protons. The following gamma rays have been found: a 432-kev gamma ray from the ${\mathrm{B}}^{10}(p, \ensuremath{\alpha}\ensuremath{\gamma}){\mathrm{Be}}^{7}$ reaction, a 718-kev gamma ray from inelastic scattering in ${\mathrm{B}}^{10}$, and a high-energy gamma ray from the reaction ${\mathrm{B}}^{10}(p, \ensuremath{\gamma}){\mathrm{C}}^{11}$ Excitation curves and cross sections for these gamma rays are given.

The spectrum of gamma radiation emitted when ${\mathrm{B}}^{11}$ is bombarded by protons has been investigated with a NaI scintillation counter. Capture gamma rays have been found which occur in a direct transition to the ground state of ${\mathrm{C}}^{12}$ and a cascade transition through a level in ${\mathrm{C}}^{12}$ at 4.45 Mev. Yield curves for these gamma rays have been obtained for proton energies up to 2.8 Mev, and the cross sections for emission of the various gamma rays are given. In addition to the well-known resonance at 0.163 Mev, new resonances have been found at 0.675 Mev with $\ensuremath{\Gamma}=0.33 \mathrm{Mev}\mathrm{and} 1.388 \mathrm{Mev}$ with $\ensuremath{\Gamma}=1.27$ Mev. Spin and parity assignments for these states which are deduced from the results of this and the ${\mathrm{B}}^{11}(p, \ensuremath{\alpha}){\mathrm{Be}}^{8}$ reactions are ${2}^{\ensuremath{-}}$ (or ${3}^{+}$) and ${1}^{\ensuremath{-}}$, respectively. A 2.13-Mev gamma ray has also been observed, which is produced in an inelastic scattering reaction involving the first excited state of ${\mathrm{B}}^{11}$. This reaction exhibits a resonance at 2.664 Mev with a width of 48 kev. The cross section at resonance is 3.1\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}26}$ ${\mathrm{cm}}^{2}$.

Distributions of electrons elastically scattered by He/sup 3/ and T are compared in order to analyze the three-body forces acting in these mirror nuclei. The charge and magnetic form factors for the nuclei are calculated. Three of these form factors are nearly equal to one another but the charge form factor of He/sup 3/ is different from the other three. (T.F.H.)

Weak, low-energy capture radiation has been observed when ${\mathrm{C}}^{12}$ is bombarded by protons of energy 1-3 Mev. From the observed dependence of gamma-ray energy on proton bombarding energy, it is concluded that the radiation arises from a transition to the 2.369-Mev level in ${\mathrm{N}}^{13}$. Since the latter level is unstable to proton emission a second gamma ray is not observed. The excitation curve for this reaction shows an anomaly in the neighborhood of 1.7 Mev, which can be explained as resulting from the interference of a nonresonant $p$-wave radiation with the radiation from the 3.511-Mev, ${P}_{\frac{3}{2}}$ level in ${\mathrm{N}}^{13}$.