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This report summarizes evaluations of vegetable varieties conducted by the Horticultural Research Program of the University of Alaska-Fairbanks. The objective of this research is to select varieties of vegetables that are adapted to the environment of interior Alaska. Vegetable crops whose adaptability may be improved through development of improved cultural techniques are also identified. The selection effort is directed at finding varieties useful to both commercial growers and home gardeners. Varieties are chosen for inclusion in the variety tests on the basis of their description, the latitude of origin, and the record of the plant-breeding programs for producing kinds that have previously been found adapted. Standard recommended varieties are included in the trials for comparison.Introduction -- Weather Summary, 1985 -- Table 1. Climatic Data for the Fairbanks Growing Season: 1984, 1985, and the Long-Term Average -- Figure 1. Daily Weather Data, May through September, 1985, University Experiment Farm, Fairbanks, AK -- Table 2. Artichoke Variety Trial, 1985 -- Table 3. Carrot Variety Trials, Bottomland, 1985 -- Table 4. Celery Variety Trials, 1985 -- Table 5. Eggplant Variety Trials, 1985 -- Table 6. Broccoli Variety Trials, 1985 -- Table 7. Brussels Sprouts Variety Trials, 1985 -- Table 8. Cauliflower Variety Trials, 1985 -- Table 9. Crisphead Lettuce Variety Trials, Bottomland, 1985 -- Table 10. Green Pea Variety Trials, 1985 -- Table 11. Pepper Variety Trials, 1985 -- Table 12. Potato Variety Trials, Bottomland, 1985 -- Table 13. Slicing Cucumber Variety Trials, 1985 -- Table 14. Summer Squash Variety Trials, 1985 -- Table 15. Sweet Corn Variety Trials, 1985 -- Table 16. Mulched Tomato Variety Trials, 1985 -- Table 17. Unmulched Tomato Variety Trials, 1985 -- Table 18. Container Tomato Variety Trials, 1985 -- Table 19. Winter Squash Variety Trials, 1985 -- Table 20. Pumpkin Variety Trials, 1985 -- Table 21. Miscellaneous Vegetable Trials -- Seed Source

Low-energy Mott-Hubbard excitations in LaMnO_3 probed by optical ellipsometry

We present a comprehensive ellipsometric study of an untwinned, nearly stoichiometric LaMnO_3 crystal in the spectral range 1.2-6.0 eV at temperatures 20 K < T < 300 K. The complex dielectric response along the b and c axes of the Pbnm orthorhombic unit cell, \epsilon^b(\nu) and \epsilon^c(\nu), is highly anisotropic over the spectral range covered in the experiment. The difference between \epsilon^b(\nu) and \epsilon^c(\nu) increases with decreasing temperature, and the gradual evolution observed in the paramagnetic state is strongly enhanced by the onset of A-type antiferromagnetic long-range order at T_N = 139.6 K. In addition to the temperature changes in the lowest-energy gap excitation at 2 eV, there are opposite changes observed at higher energy at 4 - 5 eV, appearing on a broad-band background due to the strongly dipole-allowed O 2p -- Mn 3d transition around the charge-transfer energy 4.7 eV. Based on the observation of a pronounced spectral-weight transfer between low- and high-energy features upon magnetic ordering, they are assigned to high-spin and low-spin intersite d^4d^4 - d^3d^5 transitions by Mn electrons. The anisotropy of the lowest-energy optical band and the spectral weight shifts induced by antiferromagnetic spin correlations are quantitatively described by an effective spin-orbital superexchange model. An analysis of the multiplet structure of the intersite transitions by Mn e_g electrons allowed us to estimate the effective intra-atomic Coulomb interaction, the Hund exchange coupling, and the Jahn-Teller splitting energy between e_g orbitals in LaMnO_3. This study identifies the lowest-energy optical transition at 2 eV as an intersite d-d transition, whose energy is substantially reduced compared to that obtained from the bare intra-atomic Coulomb interaction.Comment: 10 pages, 14 figure

Spectroscopy on two coupled flux qubits

We have performed spectroscopy measurements on two coupled flux qubits. The qubits are coupled inductively, which results in a $\sigma_1^z\sigma_2^z$ interaction. By applying microwave radiation, we observe resonances due to transitions from the ground state to the first two excited states. From the position of these resonances as a function of the magnetic field applied we observe the coupling of the qubits. The coupling strength agrees well with calculations of the mutual inductance

A Preliminary Report on Unique Hail and Tornadic Storm Observations in Central Illinois and Eastern Indiana on 3 April 1974

published or submitted for publicationis peer reviewedOpe

Helix versus coil polypeptide macromers: gel networks with decoupled stiffness and permeability

As a platform for investigating the individual effects of substrate stiffness, permeability, and ligand density on cellular behavior, we developed a set of hydrogels with stiffness tuned by polymer backbone rigidity, independent of cross-link density and concentration. Previous studies report that poly(propargyl-L-glutamate) (PPLG), synthesized by ring-opening polymerization of the N-carboxy anhydride of γ-propargyl-L-glutamate (γpLglu), adopts a rigid a-helix conformation: we hypothesized that a random copolymer (PPDLG) with equal amounts of γpLglu and γ-propargyl-D-glutamate (γpDglu) monomers would exhibit a more flexible random coil conformation. The resulting macromers exhibited narrow molecular weight distributions (PDI = 1.15) and were grafted with ethylene glycol groups using a highly efficient “click” azide/alkyne cycloaddition reaction with average grafting efficiency of 97% for PPLG and 85% for PPDLG. The polypeptide secondary structure, characterized via circular dichroism spectroscopy, FTIR spectroscopy, and dynamic light scattering, is indeed dependent upon monomer chirality: PPLG exhibits an α-helix conformation while PPDLG adopts a random coil conformation. Hydrogel networks produced by cross-linking either helical or random coil polypeptides with poly(ethylene glycol) (PEG) were analyzed for amount of swelling, gelation efficiency, and permeability to a model protein. In addition, the elastic modulus of helical and coil polypeptide gels was determined by AFM indentation in fluid. Importantly, we found that helical and coil polypeptide gels exhibited similar swelling and permeability but different stiffnesses, which correspond to predictions from the theory of semi-flexible chains.National Institutes of Health (U.S.) (R01 EB10246)National Science Foundation (U.S.). Emergent Behaviors of Integrated Cellular System

A second order minimality condition for the Mumford-Shah functional

A new necessary minimality condition for the Mumford-Shah functional is derived by means of second order variations. It is expressed in terms of a sign condition for a nonlocal quadratic form on $H^1_0(\Gamma)$, $\Gamma$ being a submanifold of the regular part of the discontinuity set of the critical point. Two equivalent formulations are provided: one in terms of the first eigenvalue of a suitable compact operator, the other involving a sort of nonlocal capacity of $\Gamma$. A sufficient condition for minimality is also deduced. Finally, an explicit example is discussed, where a complete characterization of the domains where the second variation is nonnegative can be given.Comment: 30 page