Vestitol: A phytoalexin with insect feeding-deterrent activity

A major feeding deterrent forCostelytra zealandica larvae was isolated from the root of the resistant pasture legumeLotus pedunculatus and was identified as 3R-(—)-vestitol. This compound was also identified in feeding deterrent-activeL. pedunculatus leaf extracts. (—)-Vestitol and a secondLotus isoflavan, sativan, have been reported to have phytoalexin activity, and the implications of this for the study and understanding of insect resistance are briefly discussed.     

Mercury concentrations in fish inhabiting two polluted lakes in Northern Canada

The concentrations of total mercury in the sediments, water and fish of Giauque Lake and Thompson Lake in northern Canada were determined during 1977 and 1978. Both lakes had formerly received mercury-laden industrial discharges, which were terminated in 1968 (Giauque Lake) and 1949 (Thompson Lake). In Giaque Lake, lake trout (Salvelinus namaycusy) contained an average of 3.79 mg kg⁻¹ in their muscle while the average concentrations in northern pike (Esox lucius) and round whitefish (Prosopium cylindraceum) were 1.75 and 1.22 mg kg⁻¹ respectively. About 7% of the lake's bottom contained mercury levels of > 500 μg kg⁻¹ (dry weight) but, in the water, concentrations were always below detectable limits (0.2 μg l⁻¹). In Thompson Lake, mercury levels in northern pike averaged 1.69 mg kg⁻¹, whereas in lake whitefish (Coregonus clupeaformis), the highest recorded value was 0.6 mg kg⁻¹. Although mercury was usually not detectable in the water column, there was heavy contamination of the sediments, with values reaching 1300 μg kg⁻¹. In addition, approximately 15% of the lake bottom contained mercury in excess of 500 μg kg⁻¹. Based on these data, it is concluded that: (1) northern pike are still accumulating mercury from exposed tailings which were deposited in Thompson Lake 30 years ago, and (2) contamination of only a small part of a lake may result in high levels in fish throughout the lake: this is probably due to the movement of fish from contaminated to noncontaminated areas.     

Measurement of dairy calf behavior prior to onset of clinical disease and in response to disbudding using automated calf feeders and accelerometers

We determined if feeding and lying behavior, recorded by automatic calf feeding systems (ACFS) and accelerometers, could be used to detect changes in behavior before onset of neonatal calf diarrhea (NCD) or in response to disbudding pain in dairy calves. At 4 d of age, 112 calves had accelerometers attached to their hind leg and were housed in pens with ACFS. Calves were examined daily for signs of illness or injury. Of the 112 calves monitored, 18 were diagnosed with NCD; activities of calves with NCD were then compared with those of 18 healthy controls (calves that had no symptoms of NCD, other illnesses, or injury). Feeding (milk consumption and the number of rewarded and unrewarded visits to the feeder) and lying behavior during the 5 d leading up to calves displaying clinical signs of NCD were analyzed. Calves with NCD performed fewer unrewarded visits and consumed less milk than healthy calves during the 2- and 4-d periods before diagnosis with NCD, respectively. Calves with NCD tended to perform fewer lying bouts than healthy calves over the 5-d period before diagnosis with NCD. At 3 wk of age, a subset of 51 healthy calves were allocated to 1 of 5 treatment groups: (1) sham handling (SHAM, n = 10), (2) cautery disbudding (DB, n = 11), (3) administration of local anesthetic (LA) and DB (LA+DB, n = 11), 4) administration of a nonsteroidal anti-inflammatory drug (NSAID) and DB (NSAID+DB, n = 9), and (5) administration of LA, NSAID and DB (LA+NSAID+DB, n = 10). Feeding and lying behavior were recorded continuously for 24 h pre- and postdisbudding. We found no effect of treatment on the number of rewarded or unrewarded visits to the feeder and milk volume consumed 24 h before administration of treatments. During the 24-h postdisbudding period, SHAM calves performed more unrewarded visits than DB, LA+DB, and NSAID+DB calves, but the number of unrewarded visits did not differ between SHAM and LA+NSAID+DB calves. During the first hour of the posttreatment period we noted a difference in lying times among treatments, with DB and NSAID+DB calves spending less time lying than SHAM calves and lying times being similar between SHAM, LA+DB, and LA+NSAID+DB calves. The ACFS and accelerometers have the potential to automatically gather valuable information regarding health status and pain in calves. Therefore, it may be advantageous to combine both of these measures (ACFS and accelerometers) when evaluating NCD on farm or pain in calves in future research.     

Comparison of the effects of different types of soya milk on the total antioxidant capacity of black tea infusions

Experimental evidence has shown that the polyphenols in black tea exhibit strong antioxidant potential in vitro and in vivo. The objective of the present study was to analyse and compare the total antioxidant capacity (TAC) of five brands of tea and to evaluate whether the addition of different varieties of soya milk decreased the TAC compared to semi-skimmed bovine milk. Each of the teas analysed was a significant source of antioxidants (7796–10,434 μmol/l FRAP). The addition of milk lowered the TAC of each of the teas analysed. When compared to tea with semi-skimmed bovine milk, each of the five teas analysed had either significantly higher antioxidant values or no change after the addition of soya milk. The addition of soya milk to black tea may be a useful alternative to semi-skimmed bovine milk if wishing to maintain the overall antioxidant potential of the tea infusion.     

Social desirability, item-response time, and item significance.

Pathological personality item responses have been shown to relate to the social desirability scale values of test items. It was hypothesized that both social desirability and pathological item-response frequency might vary as a function of the time permitted to answer test items. Two groups of Ss were administered the items of the Maslow, Birch, Honigman, McGrath, Plason, and Stein Security-Insecurity Inventory. Social desirability scale values for the items were established. Maximal reading time required for each item was also determined, and both groups were permitted to view each item for the same established length of time. 1 group was allowed 2 sec., the other group 10 sec. for each response. It was observed that time pressure reduced the number of pathological item responses, and that items scaled either high or low in social desirability tended to be answered in the socially desirable direction under time pressure. Females generally provided more critical or pathological item responses than did males. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hydrogen refueling station compression and storage optimization with tube-trailer deliveries

Hydrogen refueling stations require high capital investment, with compression and storage comprising more than half of the installed cost of refueling equipment. Refueling station configurations and operation strategies can reduce capital investment while improving equipment utilization. Argonne National Laboratory developed a refueling model to evaluate the impact of various refueling compression and storage configurations and tube trailer operating strategies on the cost of hydrogen refueling. The modeling results revealed that a number of strategies can be employed to reduce fueling costs. Proper sizing of the high-pressure buffer storage reduces the compression requirement considerably, thus reducing refueling costs. Employing a tube trailer to initially fill the vehicle's tank also reduces the compression and storage requirements, further reducing refueling costs. Reducing the cut-off pressure of the tube trailer for initial vehicle fills can also significantly reduce the refueling costs. Finally, increasing the trailer's return pressure can cut refueling costs, especially for delivery distances less than 100 km, and in early markets, when refueling stations will be grossly underutilized.     

Response of winter wheat to N-fertiliser: Dynamic model

A concise computer simulation model is described for calculating the growth and N-content of winter-wheat. The validity of the model was tested by means of a new application of statistical theory against the results of nationwide fertiliser experiments having different designs. There was agreement within the limits of experimental error between the measured and simulated values of both total plant and of grain dry weight over the entire range of N-fertiliser treatments in the different experiments. The model also gave good estimates of the %N in the grain provided N-fertilizer levels were not high. Response curves, calculated from the model for grain yield, grain %N, are given for different combinations of potential yield, mineralisation rate and the distribution of inorganic-N down the soil profile.