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High yielding cultivars adapted to conventional and organic production system would maximize efficiency of nutrient usage and reduce dependence on pesticides. The objective of this study was to determine if separate breeding efforts are needed to obtain high yielding dry bean breeding lines for on-farm organic (FO) and on-farm conventional (FC) production systems. The six highest yielding breeding lines selected from each of FO, FC, and on-station conventional (SC) production systems in two populations (1WS, 2WS) and their parents were evaluated for days to maturity, 100-seed weight, and seed yield in 2007 and 2008. The production system and genotype effects were significant (P ≤ 0.01) for all three traits. Seed yield gains were between 10.5% in FC and 15.0% in SC in 1WS and between 6.2% in FO and 21.0% in SC in 2WS. Seed yield of breeding lines selected in SC was higher than those selected in FC and FO when tested across the three production systems. The SC seed yield was positively associated with seed yield in FC and FO in 2WS and with seed yield in FC in 1WS. The FC and FO seed yields were positively associated only in 2WS. The highest yielding breeding lines within and across the three PS varied by the production system in which they were selected. Thus, breeding high yielding cultivars in SC or FC may serve FO in some populations, whereas a separate breeding for FO and FC may be justified in other populations if the accompanying seed yield gains would off-set the added costs involved in the production system specific breeding.

High-yielding cultivars adapted to stressed and nonstressed production systems (PS) would maximize efficiency of soil water and nutrient usage, compete well with weeds, resist diseases and insect pests, and reduce dependence on water, fertilizer, and pesticide. The objectives of this study were to (i) determine the performance of dry bean (Phaseolus vulgaris L.) landraces and cultivars across seven stressed and nonstressed PS, (ii) identify high-yielding cultivars within and across PS, and (iii) determine associations among PS. Three landraces and 13 cultivars were evaluated for days to maturity, 100-seed weight, and yield in 2003 and 2004. The PS and genotype effects and their interactions with years were significant (P < 0.01). The mean yield (740 kg ha-1), 100-seed weight (28 g), and days to maturity (81 d) were least in the on-farm organic low input (OFOL) PS. The greatest mean yield (2740 kg ha-1) was obtained in the on-station conventional (OSCN) PS, while the greatest 100-seed weight (35 g) and days to maturity (95) were obtained in the on-farm low soil fertility (OFLF) PS. Red genotypes yielded more across all PS. 'Bill Z' in OSCN and onfarm organic high-input (OFOH) PS, 'UI 239' in on-station continual bean production (OSCB), CO46348 in on-station drought-stressed production (OSDS), 'Matterhorn' in on-farm conventional (OFCN), 'NW 63' in OFLF, and 'Buster' in OFOL had high yield. CO46348, UI 239, NW 63, and Bill Z had high yields across PS. Positive associations for yield in the OFCN occurred with yield across all PS except OFOL. The latter was not correlated with other PS. Thus, testing in the OFCN PS would be pivotal for development of high-yielding cultivars for diverse PS, while testing at OFOL would need to be done for cultivars developed for use in that PS. © Crop Science Society of America.

Large-seeded (45 g 100 seed weight –1 ), high-yielding, and high-quality Hungerford (Reg. No. CV-285, PI 653258) and Sawtooth (Reg. No. CV-286, PI 653259) great northern dry bean (Phaseolus vulgaris L.) cultivars were developed at the University of Idaho-Kimberly Agricultural Research and Extension Center. The Idaho Agricultural Experiment Station released Hungerford and Sawtooth on 12 Apr. 2007. Hungerford and Sawtooth are full-season (95–100 d maturity) cultivars adapted to the western United States that have resistance to Bean common mosaic virus (an aphid-vectored potyvirus) and rust [caused by Uromyces appendiculatus (Pers.) Ung.]. Both also have moderate to high levels of resistance to heat, drought, and soil zinc defi ciency and manganese toxicity.

Pinto dry bean (Phaseolus vulgaris L.) 'Kimberly' (Reg. No. CV-283, PI 653256) and 'Shoshone' (Reg. No. CV-284, PI 653257) were developed at the University of Idaho-Kimberly Agricultural Research and Extension Center. Both were released by the Idaho Agricultural Experiment Station on 12 Apr. 2007. Kimberly is a full-season (100 d to maturity) and Shoshone is an early- to medium-maturing cultivar. Both have light-colored and slow-darkening pinto seed. Both are high-yielding, widely adapted cultivars and possess the bc-3 and l genes imparting resistance to all strains of Bean common mosaic virus and Bean common mosaic necrosis virus (an aphid-vectored potyvirus) and to rust [caused by Uromyces appendiculatus (Pers.) Ung.]. Both also have moderate to high levels of resistance to heat and drought. However, both are susceptible to soil zinc deficiency and manganese toxicity.

Continual dry bean (CB, Phaseolus vulgaris L.) production in the same field for 2 or more consecutive years is common worldwide. However, the effects on and performance of dry bean cultivars in the CB production system is not known. The objectives of this research were to (i) determine effects of the CB production system on seed yield, seed weight, and days to maturity of race Durango cultivars; (ii) determine the correlations for those three traits between the CB and rotational production (RP) systems; and (iii) identify superior cultivars within and across both production systems. Medium-sized (25-40 g 100 seed -1 ) cultivars of great northern (8), pink (3), pinto (9), and red (5) of race Durango released between 1932 and 1998 were evaluated from 1999 to 2001 in a field that had been under 50 yr of CB production at the University of Idaho, Kimberly Research and Extension Center. Concurrently, they were evaluated under the standard RP system. The cultivar effects and cultivar X year interaction effects were significant (P < 0.01) for seed yield, seed weight, and days to maturity in both production systems. Continual dry bean production reduced mean seed yield by 68%, seed weight by 11%, and days to maturity by 6 d. Large differences among cultivars existed within and between market classes in both production systems. On average, great northern and pinto cultivars had the greatest reduction (71%) and pink (56%) followed by red (66%) cultivars had the least reduction in seed yield due to CB production. Cultivars UI 537, UI 239, Viva, and Harold had the highest levels of resistance to CB production. Despite significant (P < 0.01) positive phenotypic correlation between the two production systems for seed yield (r 2 = 0.70), seed weight (r 2 = 0.90), and days to maturity (r2 = 0.67), testing of dry bean cultivars using both production systems is suggested for identification of superior cultivars to be grown either within or across production systems.

This computerized linear programming study was performed to formulate low-cost, commercially processed, blended weaning foods, and even less expensive, home-prepared, blended wearing foods, with excellent energy and protein value for use in areas of Lusaka, Zambia, where the risk of malnutrition is high. Ingredient input information included proximate and essential amino acid analyses, into-the-blend costs, and factors for gastrointestinal absorption of proteins and total energy. For most computed mixtures, the minimum cost at selected levels of absorbed protein quality was optimized. Formulations were determined, with calculated cost and nutritional parameters, using only mother-favoured ingredients or, alternatively, selections from among all listed market ingredients; fat versus fat plus sugar as concentrated energy; for different seasons (home-prepared); and, for commercial blends, both with and without puridies amino acid(s) that do or do not include vitamin-antioxidant-mineral mix. The methodology should be widely applicable elsewhere.

An analysis is presented to accurately calculate the effects of photon recycling on the minority‐carrier lifetime in the active region of GaAs/Al0.3Ga0.7As double heterostructures. It is shown that the minority‐carrier lifetime multiplication factor and resulting minority‐carrier lifetime are dominated by multiple reflection propagation for samples with thicknesses of approximately less than 1.0 μm. The calculated results are in good agreement with previously published experimental data on the variation of the minority‐carrier lifetime multiplication factor with active region thickness, indicating the usefulness of the analysis to accurately model the effects of photon recycling in transient photoluminescence measurement of thin devices. This may lead to accurate determination of the minority‐carrier lifetime, diffusion coefficient, and surface recombination velocities at the levels of interest for device applications.

A two dimensional finite element model for the simulation of the advancing front in reaction injection molding (RIM) is presented. The model is based on the solution of the full Navier-Stokes equation for the computation of the velocity and pressure. The arbitrary Lagrange-Euler method is used for the moving front. The method of characteristics is used for the solution of the mass-and energy equations. An automatic remeshing algorithm is used to prevent element distortion and to optimize element size and number. Numerical results are presented for flow into a complex domain in order to illustrate the versatility of the method.

Numerical investigations of the effect of mixed convection on the fluid flow pattern and heat transfer at the boundary layer of a packed bed are reported. A volume-averaged Navier-Stolces equation incorporating the Boussinesq approximation is used to predict the fluid flow, and a volume-averaged heat balance equation, the heat transfer. An exponential variation in the porosity of the packing is assumed in the region near the wall. Simulations are performed using a modified penalty Galerkin finite-element method. The Nusselt number is found to depend on the Grashof to Reynolds number ratio, Graetz number, and ratio of thermal conductivity of the solid and fluid phases. The heat transfer rate is enhanced by a positive Grashof number and hindered by a negative value. The velocity and temperature profiles in the bed are also found to be strong functions of the Gr/Re2 ratio. At higher values of this ratio the flow becomes unsteady

Patterned single‐crystal GaAs/Ge layers are grown on Si substrates by molecular beam epitaxy deposition through a bilayer mask. The ability to pattern device‐quality GaAs structures on Si allows for integration of GaAs and Si devices on a monolithic chip. In this paper we describe the experimental details of a process that could be used to fabricate such circuits. The Si substrate, before growth, is patterned using a bilayer silicon nitride/silicon dioxide mask and conventional photolithographic techniques. During growth, in areas where the Si substrate is exposed, the GaAs/Ge layers grow epitaxially. After growth, a chemical etch is used that dissolves the mask, retaining the single‐crystal GaAs/Ge pattern. The bilayer mask yields good pattern replication and prevents diffusion of Ga and As into the underlying Si devices, as shown by secondary ion mass spectroscopy data. The bilayer mask also aids in the lift‐off process where thick GaAs/Ge layers are required and 100% lift‐off yield is mandatory. Sample morphology and crystallinity are examined by scanning electron microscopy and reflection high‐energy electron diffraction.

A modification of the Marquardt method is combined with a Galerkin finite element method to produce an efficient algorithm for the solution of the steady-state Navier-Stokes equation at moderate Reynolds numbers. The algorithm is shown to be 3 to 4 times faster than more conventional algorithms based on the modified Newton method with loading on the nonlinear term. Numerical results are presented for a 4:1 contraction at Reynolds numbers in the range 400–1000 and for problems varying in size from 1107 to 3576 equations.

Optical propagation in an anisotropic rectangular semiconductor waveguide is established, using a plane-wave approximation. The discrete modes of this guide are hybrid. On the basis of this model, simulation (λ=l·27μm) shows that a π phase difference is introduced between the two fundamental modes in the rib p+(InP)-n-(GaInAsP)-n+(InP) structure at — 14·6 V, for a device length of 2·5 mm. Electro-optic switching in the adjacent MOS waveguide pair is obtained for the bias 0 and — 20 V. The proposed device geometry is compatible with the liquid-phase epitaxial-growth techniques of the GalnAsP alloy system

This study has demonstrated the feasibility of producing a corn-based, PL 480-type food blend containing glandless cottonseed flour that is comparable in nutritional quality, maternal and child acceptability, and child gastrointestinal tolerance to the extensively used US Food-for-Peace Program food, corn-soy-milk. The blend containing glandless cottonseed flour offers the economic advantage of not requiring an animal protein component. However, at the present time glandless cottonseed flour is not economically competitive with soy flour. With more extensive cultivation of glandless cottonseed, the prospect of using this commodity in nutritious food blends will be more favourable.

Heterojunction solar cells have low‐cost potential for meeting the long term economic goals for the photovoltaic technology. In this paper, a critical technical evaluation of the ITO/GaAs solar cell is presented, emphasizing the factors limiting the performance of the device. The devices are fabricated on p‐type (Be‐doped) GaAs grown by MBE, with the ITO deposited by ion beam techniques. Light and dark J‐V characteristics are presented and compared for these devices. The formation of buried homojunctions is postulated for cells damaged due to ion beam deposition, leading to higher Voc and low Jsc. Heterojunction formation is found for minimally disrupted GaAs surfaces. AES depth profiles are used to evaluate the chemical width of the ITO/GaAs interfaces. Electrical data characterizing the ITO/GaAs interface are obtained using EBIC, C‐V and intensity dependent Voc‐Jsc characteristics.

Soybean flour and various derivatives, with different natural, interacting primary antioxidants and synergists can stabilize lipids in formulated foods. Soybean flour has been shown to be a basic source of such antioxidant compounds as isoflavone glycosides and their derivatives, phospholipids, tocopherols, amino acids and peptides. There may be some antioxidant impact from aromatic amines and sulfhydryl compounds. Successful efforts have been made to concentrate the antioxidant activity in soy flour by aqueous extraction and by extraction with various organic solvents. Residual antioxidant activity has been reported in food systems containing soy protein concentrates, isolates and textured vegetable protein. Soy protein hydrolyzates have antioxidant activity which is associated with free amino acids and lower molecular weight peptides.

The heat transfer characteristics of a Newtonian fluid in a two-dimensional, planar, right-angled tee branch are studied over a range of inlet Reynolds numbers and Grashof numbers. The flow and heat transfer equations, subject to the Boussinesq approximation, are solved using a finite-element discretization. The effects of the branch length and the grid size on the interior flow field are examined to assess the accuracy of the solutions. Results are presented for two types of experimentally realizable boundary conditions—equal exit pressure at the outlet of each branch and specified flow split between the branches. The thermal boundary condition of uniform wall temperature is examined. The effect of increasing Reynolds number is to increase the size and strength of the recirculation zones in both the main and side branches, while that of increasing Grashof number is to decrease such an effect. For the case of equal exit pressures there is a significant flow reversal in the side branch and the exit flow ra...

A system for controlling the rate of evaporation and final film thickness of evaporated insulating films is described. In this system an incremental weightmeter measures and controls the evaporation rate of a vapour source and cuts it off when the desired weight has been deposited. The weightmeter consists of a microammeter movement stabilized by an optical servo system. Its output is a current proportional in sign and magnitude to the force on a vane placed in the vapour stream. It has been used in the laboratory manufacture of multilayer circuitry to control the deposition of silicon monoxide insulating films and to study how rate of evaporation affects the deposited film constitution, density, dielectric constant and insulating properties.

Single crystal GaAs layers have been grown on Si substrates with an intermediate Ge layer. Both the Ge and subsequent GaAs are grown in situ by molecular beam epitaxy (MBE). Cross‐sectional transmission electron microscopy studies show GaAs surface dislocation densities on the order of 107 cm−2. The quality of the GaAs is indicated by a mobility within 15% of that measured on GaAs/GaAs MBE structures doped at the same level. This material also exhibits a photoluminescence signal with a room‐temperature intensity about 50% of GaAs grown on GaAs, and with a similar half‐width. In this letter, electron diffraction, optical and electrical data are presented for n‐type GaAs/Ge/Si structures. In addition, a selective lift‐off technique is demonstrated, with possible applications in the development of monolithic GaAs/Si integrated circuits.

A novel time‐of‐flight technique has been developed for simultaneously measuring minority‐carrier lifetime and diffusivity in homojunctions. A pulsed dye laser produces electron‐hole pairs near the front surface of the device. A delay occurs before the onset of photocurrent due to the diffusion transit time of minority carriers to the junction. An analysis of this effect by both a simplified analytical model and a computer simulation gives similar results for the current as a function of time. A fit of the theory to experimental data on Al0.25Ga0.75As n/p homojunctions produces minority‐carrier lifetime, diffusivity, and diffusion length.

The minority‐carrier lifetime has been measured by time‐resolved photoluminescence in epitaxial films of GaAs grown by metalorganic chemical vapor deposition. The measured lifetimes in thicker devices are 4 to 6 times the theoretical or radiative lifetime. These long lifetimes are the result of photon recycling or self‐generation of the self‐absorbed radiation.

Efficient indium tin oxide (ITO)/p‐InP solar cells have been fabricated by ion beam deposition. In this letter, a critical evaluation of the ITO/InP interface is presented using complementary capacitance‐voltage and ion microprobe measurements. We have found that deposition of ITO produces a semi‐insulating region at the InP surface. This high resistivity layer extends about 750 A into the bulk. We have evidence that this region is due to surface accumulation of compensating impurities.

Transferred‐electron oscillation in devices employing GaxIn1−xAsyP1−y as the active material has been observed. An oscillation threshold average field of (5.5–8.6) ×103 V/cm was determined for 1.05‐eV band‐gap material having x and y values of approximately 0.13 and 0.37, respectively. A pulsed device had an efficiency of 0.5% at 27.49 GHz.

The 0 K electron effective mass in an In0.9Ga0.1As0.22P0.78 epitaxial layer has been calculated from the temperature dependence of Shubnikov–de Haas oscillation amplitudes, giving m*=0.060m0. The measured value is compared to values m*=0.059m0 and m*=0.058m0 obtained from interpolations of the masses of related binary compounds by two different methods.

Very strong capacitance‐voltage dispersive effects are observed in mercury/indium phosphide Schottky diodes. These effects are related to a partially compensated region at the surface for which the Debye length is relatively large. The small‐signal capacitance is indicative of a critical dielectric relaxation time exceeding the period of the ac probe. This effect may be used to characterize the majority‐carrier profile in lightly doped or low mobility semiconductors.

The letter describes investigations made into the electrical resistance of evaporated films of lead, tin, indium and gold, less than 600 mA thick. It was found that lower-resistance films could be obtained if arrangements were made to reduce the accumulated charge appearing on the substrate.