Inclusive electron scattering is measured with 4.045 GeV incident beam energy from C, Fe, and Au targets. The measured energy transfers and angles correspond to a kinematic range for Bjorken x . 1 and momentum transfers from Q 2 1 7 ͑GeV͞c͒ 2 . When analyzed in terms of the y-scaling function the data show for the first time an approach to scaling for values of the initial nucleon momenta significantly greater than the nuclear matter Fermi momentum (i.e., .0.3 GeV͞c). High energy electron scattering from nuclei can provide important information on the wave function of nucleons in the nucleus. In particular, with simple assumptions about the reaction mechanism, scaling functions can be deduced that, if shown to scale (i.e., are independent of length scale or momentum transfer), can provide information about the momentum and energy distribution of nucleons in a nucleus. Several theoretical studies [1][2][3][4] have indicated that such measurements may provide direct access to short-range nucleon-nucleon correlations.The concept of y scaling in electron-nucleus scattering was first introduced by West [5] and Kawazoe et al. [6]. They showed that in the impulse approximation, if quasielastic scattering from a nucleon in the nucleus was the dominant reaction mechanism, a scaling function F͑ y͒ could be extracted from the measured cross section which was related to the momentum distribution of the nucleons in the nucleus. In the simplest approximation the corresponding scaling variable y is the minimum momentum of the struck nucleon along the direction of the virtual photon. In general the scaling function depends on both y and momentum transfer-F͑ y, Q 2 ͒-but at sufficiently high Q 2 (2Q 2 is the square of the four-momentum transfer) the dependence on Q 2 should vanish yielding scaling. However, the simple impulse approximation picture breaks down when the final-state interactions (FSI) of the struck nucleon with the rest of the nucleus are included. Previous calculations [7][8][9][10][11][12][13][14] suggest that the contributions from final-state interactions should vanish at sufficiently high Q 2 . A previous SLAC measurement [15] suggested an approach to the scaling limit for heavy nuclei but only for low values of j yj , 0.3 GeV͞c at momentum transfers up to 3 ͑GeV͞c͒ 2 . The data presented here represent a significant increase in the Q 2 range compared to previous measurements while also extending the coverage in y.The present data were obtained in Hall C at the Thomas Jefferson National Accelerator Facility (TJNAF), using 4.045 GeV electron beams with intensities from 10-80 mA. The absolute beam energy was calibrated to 0.08% using 0.8 GeV elastic scattering from carbon and BeO targets and 4.0 GeV elastic scattering from hydrogen. The beam current was monitored with three calibrated resonant cavities. The beam energy resolution was better than 0.05% as defined by the accelerator acceptance. Solid targets of C (2.1% and 5.9% of a radiation length), Fe (1.5% and 5.8% of a radiation length), and Au (5.8% of a r...

A synthetic, chemically defined medium was developed for the initiation and growth of cell and tissue cultures of red clover (Trifolium pratense L.). The medium is broadly supportive and suitable for the culture of other legume species, including alfalfa (Medicago sativa L.), soybeans (Glycine max L.) and jack bean (Canavalia ensiformis L). Cultural variables for red clover were defined, and it is now possible to routinely establish callus cultures of red clover from reproductive and vegetative explant tissues of both mature and immature plants. Cell suspension cultures with rapid cell division rates have been established from calli by adapting the new medium to liquid culture. Organogenesis was induced in callus cultures, and the recovery of whole plants regenerated from callus has been achieved with the cultivars ‘Altaswede’, ‘Arlington’, ‘Kenstar’, ‘Redman’ and ‘Tensas’, but they did not respond equally well. Regenerated plants have been grown to maturity and were fertile. 3‐Aminopyridine was evaluated and found to possess growth‐modifying properties. It is now possible to investigate the use of tissue and cell culture techniques in red clover breeding programs.

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Somatic embryos were induced in cultures of immature soybean (Glycine max (L.) Merr) embryos, or isolated cotyledons on MS modified medium supplemented with NAA and 2,4-D, BAP and ABA. When NAA and 2,4-D were compared at similar concentrations (25 and 23 #M), 2,4-D produced larger number of somatic embryos, however, embryogenesis efficiency was improved in media containing NAA by using higher levels (100-150 #M) of the auxin. Somatic embryo morphology varied with auxin type: NAA-induced embryos more closely resembled zygotic embryos than did 2,4-D-induced embryos. Additions of BAP or ABA to auxin-containing media had either no effect or reduced embryo production, although ABA altered the morphology of 2,4-D-induced embryos. In media containing both NAA and 2,4-D, the latter was dominant in terms of embryo morphology. The effects of subculture frequency and of transfers between 2,4-D and NAA media were investigated: Subculture frequency influenced mainly the frequency of normal embryos, while preculture on 2,4-D increased subsequent embryogenesis efficiency on NAA medium but reduced the frequency of normal embryos.

The genetic effects and the relative contribution of two loci to the level of total alkaloids in burley tobacco (Nicotiana tabacum L.) were determined.The nine genotypes for a two-locus system were developed and evaluated in two environments. Significant additive effects were found at both loci, a dominance effect was significant at one locus, and the additive X additive epistatic effect was significant. All interactions between genetic effects and environments were nonsignificant. The relative dosage effects of the loci were approximately 2.4 to 1.