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Notes: Six annual legumes were evaluated as components of cereal-grass-legume intercrops in two experiments at two sites differing in elevation by 789 m. Barley (Hordeum vulgare L.) and Westerwolds rye-grass (Lolium multiflorum Lam.) were seeded on all intercrop plots. Dry-matter (DM) yield, crude protein (CP) and organic matter digestibility (OMD) were measured. DM yield and N content were used to estimate legume N fixation. Experiment 1 was conducted at both sites. At the lower site, Persian clover (Trifolium resupinatum L.) and annual alfalfa (Medicago sativa L.) accounted for 70% of the DM yield in harvest 1 (July), increased CP and OMD, but did not affect intercrop yield. They increased harvest 2 (August/September) intercrop yield by 263% and CP concentration by 65 g kg−1 DM. They increased harvest 3 (October) yield by 275% and CP concentration by 78 g kg−1 DM. Inclusion of striate lespedeza (Lespedeza striata) did not affect intercrop yield or quality. Annual legumes failed to establish at the higher elevation site and therefore had no effect on DM yield or forage quality. In Experiment 2, in which the performance of Westerwolds ryegrass was also compared with that of Italian ryegrass, and conducted at the lower site only, Persian clover and berseem clover (T. alexandrinum L.) increased CP of all three of the year's harvests. These two species contributed 29% of the DM yield in the first harvest (July) but did not affect total intercrop yield. They increased harvest 2 (August) yield by 313%. Persian clover increased harvest 3 (October) yield by 318% and berseem clover increased harvest 3 yield by 405%. Barrel medic (Medicago truncatula) and snail medic (M. scutellata) contributed 29% of harvest 1 yield, and increased both DM yield and CP content. Medics did not regrow. Aubade Westerwolds ryegrass contributed a greater percentage of the DM yield than did Maris Ledger Italian ryegrass at harvests 1 and 2. Ryegrass type did not affect total DM yield but did affect forage quality; intercrops containing the Italian ryegrass had higher CP at harvest 2 and higher OMD at harvest 3 than those containing the Westerwolds ryegrass. Over both experiments, at the lower elevation site, stands with Persian clover, berseem clover or alfalfa produced 80% of the yield of barley-ryegrass receiving 250 kg N ha−1, and 165% of the yield of unfertilized barley-ryegrass. Berseem and Persian clover fixed about the same amount of N over the growing season; 188 kg N ha−1 in Experiment 1 and 134 kg N ha−1 in Experiment 2.

Notes: “Total” ascorbic acid (TAA), L-ascorbic acid (L-AA), dehydro-ascorbic acid (DHAA), and diketogulonic acid (DKGA) were determined in fresh green peppers, frozen blanched peppers, and frozen unblanched peppers. L-AA accounted for 97% of the TAA in fresh peppers. Freezing resulted in a 9.2% decrease of TAA, a 15% decrease in L-AA, a 5% increase in DHAA and 1% increase in DKGA. Blanching did not affect the ascorbic acid levels of frozen peppers. DHAA remained relatively constant at 10% of the TAA during frozen storage. DKGA increased during frozen storage to 15% of the TAA. L-AA decreased after 8 months frozen storage (-18°C) to 75% of the TAA. Unblanched frozen peppers were superior in flavor, texture, and appearance to the blanched frozen peppers.

Notes: This study included semi-structured interviews with eight practitioners who have key roles in UK coastal management. Data from the interviews were analysed using ‘grounded theory’, which established that sources of uncertainty in decision making are diverse but can be categorised as being modelling issues, values issues, communication and ‘externalities’. At present, intuitive and implicit methods of taking uncertainty into account in decision making are much more prevalent than explicit methods. By identifying sources and implications of uncertainty, coastal managers will be in a stronger position to promote resilient systems that can cope with changing natural and social conditions.

Notes: A description is given of the computer-controlled triple-axis neutron spectrometer system installed at the PLUTO reactor at Harwell. Following the operation of the original system for several years a number of major improvements have been made which have resulted in a highly reliable system which provides the users with very powerful and extensive facilities. Following a general description of the modified spectrometer, details are given of the new computerized control system which utilizes a CAMAC modular interface and the functions of the various programs which are now available to the users are described.

Notes: Summary Near-infrared spectroscopy was used to determine biomass and glycerol concentrations in E.coli whole broth fermentation samples. For dry cell weight, a standard error of prediction (SEP) of 0.2 g/L and correlation coefficient (r) of 0.991 were obtained. The SEP and r for glycerol, carbon nutrient, were 0.3 g/L and 0.979. respectively. Off-line analysis was accomplished within 2 minutes of sampling and therefore provides the opportunity to monitor fermentations quickly enough to permit in-process development and troubleshooting.

Notes: Abstract Bioprocess optimisation is often limited by an inability to measure biomass, nutrient and by-product concentrations in a time frame which allows process adjustments. Near-infrared (near-IR) spectroscopy can potentially be used to measure each of these components within 2 minutes of sampling, using an unprocessed whole broth sample. In the present study the use of near-IR spectroscopy for at-line (rapid off-line) monitoring of biomass, glycerol, ammonium, and acetate in a recombinant Escherichia coli fed batch process was investigated. The following robust correlation models were developed for these analytes using multiple least squares linear regression (MLR): [Glycerol],gl−1 =15.957 − 2219.270* A(λ2274)−1705.041* A(λ2172); [Acetate],gl−1=27.683 −1757.258* A(λ2254)+296.903* A(λ2340)−21.325* A (λ620); [Ammonium],gl−1=−1310.502−47912.960* A (λ2148)−135149.300* A(λ1782)−27636.200* A (λ830); and [Biomass],gl−1=14.034−3.548* A(λ602/λ1134) −4286.050* A(λ928). Using these models permitted rapid simultaneous analysis of all four analytes. This improved monitoring capability was used to develop a high cell density recombinant E. coli fed-batch process in which ammonium and acetate accumulation were minimised leading to higher cell densities. By manipulation of the C : N ratio in the complex feed, the toxic effects of ammonium accumulation upon the organism were minimised, thereby facilitating the application of a carbon limited feeding strategy. The effect of these C : N ratio medium changes, upon the near-IR measurement capability, was investigated. In this process, near-IR spectroscopy has been shown to be a powerful, accurate and precise method for simultaneously measuring several key process variables. Its accuracy, precision and utility for at-line measurement and control are evaluated, particularly in reference to processes where the initial medium composition may vary, leading to changes in the chemical matrix. The potential of near-infra red for online analysis and control is discussed.