Soil water depletion rates under large grapevines

Over two consecutive seasons, daily rates of change in the water content of the top 120 cm of soil were calculated for sample sites located at 50 cm from the butts of 12 Colombard vines on Ramsey rootstock which were part of a controlled deficit irrigation experiment. Records were selected where the rate represented a change due solely to depletion of soil water by grapevine evapotranspiration (ΔS_ET). Soil water availability was quantified as a logarithmic transformation of the absolute value of the root-weighted measure of soil matric potential. ΔS_ET was negatively correlated with soil water availability and positively correlated with reference crop evapotranspiration (ETo). At very high values of soil water availability, i.e. soil matric potential between -8 and -16 kPa, and after the canopy was fully developed, ΔS_ET had a 1:1 relationship with ETo. When root-weighted soil matric potential was greater than -16 kPa, the mean values of the ratio of soil water depletion rate to reference crop evapotranspiration (ΔS_ET/ETo), varied from 0.1 to 1.2 for 30-day periods between bud burst and leaf fall. Considering the full set of measurements, ΔS_ET/ETo was highly negatively correlated with soil water availability for all 30-day periods except those less than 60 days from bud burst. In the period 150 to 179 days after bud burst, 70% of the variance in ΔS_ET/ETo was accounted for by regression on soil water availability for values of root-weighted soil matric potential between -8 and -100 kPa. During this period a fall in root-weighted soil matric potential from -10 to -42 kPa was associated with a decline in the value of ΔS_ET/ETo from 1.3 to 0.6. At both high and low values of ETo, the ratio of ΔS_ET/ETo fell linearly with declining soil water availability. The changes in values of midafternoon stem water potential and stomatal conductance associated with this decline in ΔS_ET/ETo are discussed.     

A FLOWSHEET MODEL OF A WELL-MIXED FLUIDIZED BED DRYER: APPLICATIONS IN CONTROLLABILITY ASSESSMENT AND OPTIMIZATION

ABSTRACT

A model of a well-mixed fluidized-bed dryer within a process flowsheeiing package (SPEEDUP(tm)) has been developed and applied to a parameter sensitivity study, a steady-state controllability analysis and an optimization study. This approach is more general and would be more easily applied to a complex flowsheet than one which relied on stand-alone dryer modelling packages. The simulation has shown that industrial data may be fitted to the mode outputs with sensible values of unknown parameters. For this case study, the parameter sensitivity study has found that the heat loss from the dryer and the critical moisture content of the material have the greatest impact on the dryer operation at the current operating point. An optimization study has demonstrated the dominant effect of the heat loss from the dryer on the current operating cost and the current operating conditions, and substantial cost savings (around 50% ) could be achieved with a well-insulated and airtight dryer, for the specific case studied here.     

LIQUID CIRCULATION PATTERNS AND THEIR EFFECT ON GAS HOLD-UP AND AXIAL MIXING IN BUBBLE COLUMNS

Liquid velocity profiles in a bubble column were measured with the aid of a hot-film anemometer. Two different types of profiles were detected that were characterized by the formation of a boundary layer at the column wall. Under slow flow conditions, the boundary layer is large and controls the liquid velocity profile, but in turbulent flow the boundary layer is very small and has no significant effect on the velocity profile. Microscopic and macroscopic balances were used to predict both the liquid velocity profile and the average liquid velocity.

The effect of the liquid velocity profile and average velocity on axial dispersion and gas-hold-up are analyzed and design procedures are recommended.     

Synthesis of flavonols and expression of flavonol synthase genes in the developing grape berries of Shiraz and Chardonnay (Vitis vinifera L.)

Flavonols were determined in Shiraz and Chardonnay grapes throughout berry development. The predominant flavonols were quercetin-3-glycosides with trace amounts of kaempferol-3-glycosides detected in Shiraz flowers but not in developing berries. Flavonols were present in the skin of ripening grapes but were not detected in seeds or flesh. Flavonols were also present in buds, tendrils, inflorescences, anthers and leaves. The concentration of flavonols in flowers (mg/g fresh weight) was high and decreased between flowering and berry set then remained relatively constant through berry development. The total amount of flavonols in berries (mg/berry) was low until pre-veraison then increased during berry development, particularly before veraison, the onset of ripening, in Chardonnay and during ripening in Shiraz. Two cDNA fragments with homology to genes encoding the enzyme flavonol synthase (FLS) were isolated from Shiraz flowers. In the overlapping region of the two cDNAs, they had 80% sequence identity at the nucleotide level and both had high homology to FLS genes from other plants. VvFLS1 was expressed in leaves, tendrils, pedicels, buds and inflorescences as well as in developing grapes. Expression was highest between flowering and fruit set then declined, increasing again during ripening coincident with the increase in flavonols per berry. Expression of VvFLS2 was much lower than for VvFLS1 and did not change during berry development. The results indicate that two distinct periods of flavonol synthesis occur in grapes, the first around flowering and the second during ripening of the developing berries.     

IDENTIFICATION AND CHARACTERIZATION OF SOME OXIDIZING ENZYMES OF THE MC FARLIN CRANBERRY

SUMMARY– Enzyme extracts were prepared from acetone powders with and without phenol-binding agents such as polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) and buffered PVP. The acetone-PVP combination was found most effective in reducing the polyphenolic content of the enzyme extract. Highest specific activity was obtained by using a buffered PVP extract. The pH optimum of cranberry peroxidase activity was 6.0. Heat inactivation of cranberry peroxidase was determined to follow first order kinetics. There was 90% destruction at 70, 80, and 90°C requiring 9.40, 1.60, and 0.47 min of heat treatment, respectively. Activation energy for the thermal inactivation of cranberry peroxidase was observed to be 37.2 kcal/mole. Guaicol, o-phenylene diamine (OPDA), and pyrogallol were tested for their sensitivity to cranberry peroxidase with OPDA determined as most sensitive. The pH optimum for catalse activity was found to range from 7.5 to 9.2. Kinetics for the heat inactivation of cranberry catalase was observed not to be of the first order nor zero order. Approximately 50% of the catalase activity was inactivated after heating for 17, 1.8, and 0.6 min at temperatures of 50, 60, and 70°C, respectively. The pH optimum for cranberry polyphenolase activity was determined to be 7.0. Heat inactivation of cranberry poly-phenolase was found to follow first order kinetics. There was 90% destruction at 50, 60, and 70°C requiring 15.85, 7.05, and 1.37 min of heat treatment, respectively. The activation energy for the inactivation of cranberry polyphenolase was observed to be 27.7 kcal/mole.     

Physical-Chemical Characteristics of Partially Clarified Guava Juice and Concentrate

Partially clarified guava juice concentrate was prepared from single strength guava puree (5.5°Brix) by treatment with pectinase (2 hr at 50°C), extraction of juice with a rack-and-cloth press, and vacuum concentration to 23°Brix. The concentrate had the following characteristics: density, 1.10; pH, 3.16; total acids, 4.67%; ash, 1.51%; moisture, 72.4%; ascorbic acid, 867 mg%; viscosity, 4.4 cp; and CIE L* 39.2, CIE a* 10.33, CIE b* 27.11.     

PERSONALITY CORRELATES OF FREE-ASSOCIATIVE SEX RESPONSES TO DOUBLE-ENTENDRE WORDS.

SEX RELATED RESPONSES GIVEN IN FREE ASSOCIATION TO DOUBLE-ENTENDRE WORDS WERE RELATED TO THE PERSONALITY VARIABLES OF SEX GUILT, NEED FOR HETEROSEXUALITY, AND THE SOCIAL DESIRABILITY RESPONSE SET. TESTING WAS CONDUCTED INDIVIDUALLY. VARIABLES OF SEX GUILT, SEXUAL MOTIVE STRENGTH, AND SOCIAL DESIRABILITY RESPONSE TENDENCY WERE MEASURED RESPECTIVELY BY THE MOSHER FORCED-CHOICE GUILT SCALE, THE EPPS, AND THE MARLOW-CROWNE SOCIAL DESIRABILITY SCALE. RESULTS INDICATED A POSITIVE RELATIONSHIP BETWEEN NEED FOR HETEROSEXUALITY AND ASSOCIATIVE SEXUAL RESPONSES, AND A NEGATIVE RELATIONSHIP BETWEEN SEX GUILT AND SEXUAL RESPONSIVITY. CONTRARY TO PREDICTION, ASSOCIATIVE SEXUAL RESPONSES WERE UNRELATED TO THE SOCIAL DESIRABILITY RESPONSE TENDENCY. DATA ALSO SHOWED A SIGNIFICANT NEGATIVE RELATION BETWEEN SEX GUILT AND SEXUAL NEED STRENGTH, AND A LOW POSITIVE RELATION BETWEEN SEX GUILT AND SOCIAL DESIRABILITY. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ACC Oxidase in Papaya Sections After Heat Treatment

The effect of heat treatment on 1-aminocyclopropane-1-carboxylate (ACC) oxidase in excised sections of papaya (Carica papaya L). ‘Kapoho’ fruit immersed in hot water baths was analyzed as kinetics of a set of consecutive reactions. Treatments were at 23, 28, 33, and 38°C which would be encountered during initial treatments of whole fruits during heating to fruit-center temperatures of 47°C and above. The response of ACC oxidase was considered as two consecutive reactions, one for production and one for degradation. Activation energies were compared to those reported at 43°C to 51°C. The implications of the analyses were confirmed by results for a whole-fruit hot-water dip.