Chromosome Abnormalities in Patients Treated with Chlorpromazine,Perphenazine, and Lysergide

In a chromosome study on leucocyte cultures made in 13 patients treated with chlorpromazine, 15 treated with perphenazine, and nine treated with lysergide, a significantly higher frequency of gaps, breaks, and hypodiploid cells in the patients treated with perphenazine and lysergide occurred compared with the 41 controls studied. It is concluded that if some drugs can induce major chromosome abnormalities, and less toxic alternatives are available, the latter should be used in preference.     

Learning the selectivity of V2 and V4 neurons using non-linear multi-layer wavelet networks

We investigate a non-linear network with two processing stages optimized to reduce the statistical dependencies in natural images. This network serves as a model for the neural information processing in the higher visual areas of primates (visual cortices V2-V4). The resulting population is analyzed with regard to non-linear selectivity and invariance properties. We find units that are very selective with respect to the space spanned by all possible input signals and units that are invariant with respect to certain stimulus classes. In comparison to the measured distribution of selectivity in V2 neurons, the selectivity histogram of the network units shows an even more pronounced tendency towards higher selectivities. A special property of the system is the emergence of non-linear interactions between coefficients from different scales and orientations, which are necessary for the exploitation of higher-order statistical redundancies of natural images. We extend the concept to multi-layer systems and present some simulation results.     

Determination of the drag coefficient of a toroidal plasma vortex in air

Forces acting on toroidal vortices in an unbounded medium (plasma vortices in air and vortex rings in air and water) are investigated. A solution to the equations describing such votrices is obtained. It is shown that this solution satisfactorily agrees with experiment. Based on the experimental results and the solution obtained, the drag coefficient C _x of such vortices is found. For the same Reynolds numbers, the value of C _x may be much less than the drag coefficient of a drop-shaped axisymmetric body (0.045), which is known to be the best streamlined object.     

Grazing behaviour and performance of lactating suckler cows, ewes and goats on partially improved heathlands

The foraging behaviour (grazing time and diet composition), live-weight (LW) changes and parasitic infection (faecal egg counts of gastrointestinal nematodes) of 12 beef cows, 84 ewes and 84 goats suckling their offspring, managed in mixed grazing on heathlands with 24% of improved pasture of perennial ryegrass-white clover, were studied during the years 2003 and 2006. The results showed that goats tended to graze for a longer time, and utilised significantly more heathland vegetation than cattle and sheep, including in their diet in an average of 0.39 herbaceous plants, 0.11 gorse and 0.51 heather over the grazing season, comparing with respective mean values of 0.85, 0.02 and 0.13 in cattle and sheep. Dietary overlap was higher between cattle and sheep (0.76) than between sheep and goats (0.53) or between cattle and goats (0.47). Despite the high performance of autumn-calving cows in spring, sheep had the best LW changes per livestock unit (LU) during the whole grazing season. Goats' performance per LU was lower than in sheep but higher than in spring-calving cows. Regarding offspring production, lambs had higher LW gains per LU than calves and kids. Mean nematode eggs/g fresh faeces (epg) during the grazing season were higher in goats (91 epg) compared with sheep (34 epg) and cattle (14 epg), particularly from September to December. In conclusion, sheep performed best on these heathlands with improved pasture areas if the entire grazing season was considered, despite the good level of production in spring from autumn-calving cows. The results suggested the complementary use of goats in order to increase the effective utilisation of the available vegetation, achieving production levels similar to those from spring-calving cows. Therefore, mixed flocks of sheep and goats would be the most appropriate sustainable systems from the animal production and vegetation use points of view.     

Survival and growth of Escherichia coli O157:H7 in ground, roasted beef as affected by pH, acidulants, and temperature.

A study was undertaken to determine the fate of Escherichia coli O157:H7 in ground, roasted beef as influenced by the combined effects of pH, acidulants, temperature, and time. There was essentially no change in the viable population of E. coli O157:H7 when beef salads (pH 5.40 to 6.07) containing up to 40% mayonnaise were incubated at 5 degrees C for up to 72 h. At 21 and 30 degrees C, significant (P < or = 0.05) increases in populations of the organism occurred in salads containing 16 to 32% mayonnaise (pH 5.94 to 5.55) between 10 and 24 h of incubation. Death was more rapid as the pH of acidified beef slurries incubated at 5 degrees C was decreased from 5.98 to 4.70. E. coli O157:H7 grew in control slurries (pH 5.98) and in slurries containing citric and lactic acids (pHs 5.00 and 5.40) incubated at 21 degrees C for 24 h; decreases occurred in slurries acidified to pHs 4.70, 5.00, and 5.40 with acetic acid or pH 4.70 with citric or lactic acid. At 30 degrees C, populations decreased in slurries acidified to pHs 4.70 and 5.00 with acetic acid. Citric and lactic acids failed to prevent significant increases in populations in slurries at pH 4.70 to 5.40 between 10 and 24 h of incubation. The order of effectiveness of acidulants in inhibiting growth was acetic acid > lactic acid > or = citric acid. The same order was observed for inactivation of E. coli O157:H7 in acidified (pH 5.00) beef slurry heated at 54 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of CpG methylation and target spacing on V(D)J recombination in a transgenic substrate.

We have previously described a line of transgenic mice with multiple head-to-tail copies of an artificial V-J recombination substrate and have shown that the methylation of this transgene is under the control of a dominant strain-specific modifier gene, Ssm-1. When the transgene array is highly methylated, no recombination is detectable, but when it is unmethylated, V-J joining is seen in the spleen, bone marrow, lymph nodes, and Peyer's patches but not in the thymus or nonlymphoid tissues, including brain tissue. Strikingly, in mice with partially methylated transgene arrays, rearrangement preferentially occurs in hypomethylated copies. Therefore, V-J recombination is negatively correlated with methylated DNA sequences. In addition, it appears that recombination occurs randomly between any two recombination signal sequences within the transgene array. This lack of target preference in an unselectable array of identical targets rules out simple mechanisms of one-dimensional tracking of a V(D)J recombinase complex.     

Short-term plyometric training improves running economy in highly trained middle and long distance runners

Fifteen highly trained distance runners VO(2)max 71.1 +/- 6.0 ml.min(-1).kg(-1), mean +/- SD) were randomly assigned to a plyometric training (PLY; n = 7) or control (CON; n = 8) group. In addition to their normal training, the PLY group undertook 3 x 30 minutes PLY sessions per week for 9 weeks. Running economy (RE) was assessed during 3 x 4 minute treadmill runs (14, 16, and 18 km.h(-1)), followed by an incremental test to measure VO(2)max. Muscle power characteristics were assessed on a portable, unidirectional ground reaction force plate. Compared with CON, PLY improved RE at 18 km.h(-1) (4.1%, p = 0.02), but not at 14 or 16 km.h(-1). This was accompanied by trends for increased average power during a 5-jump plyometric test (15%, p = 0.11), a shorter time to reach maximal dynamic strength during a strength quality assessment test (14%, p = 0.09), and a lower VO(2)-speed slope (14%, p = 0.12) after 9 weeks of PLY. There were no significant differences in cardiorespiratory measures or VO(2)max as a result of PLY. In a group of highly-trained distance runners, 9 weeks of PLY improved RE, with likely mechanisms residing in the muscle, or alternatively by improving running mechanics.     

Xylanase and β-xylosidase production byAspergillus niger NCIM 1207

Summary Aspergillus niger NCIM 1207 producing significantly high levels of -glucosidase was found to secrete hemicellulolytic enzymes (xylanase and -xylosidase) in the culture medium. High yields of -xylosidase were obtained when it was grown on either xylan (3%) or wheat bran (4%). Cellulose was a poor inducer of -xylosidase. The pH and temperature optima for-xylosidase were 4.5 and 65°C respectively.NCL Communication No. 3751