Search

Queen mandibular pheromone (QMP) is a potent reproductive signal to which honey bee workers respond by suppressing their ovaries and adopting alloparental roles within the colony. This anti-ovarian effect of QMP on workers can, surprisingly, be induced in other insects, including fruit flies, in which females exposed to synthetic QMP develop smaller ovaries with fewer eggs. In this study, we use the Drosophila melanogaster model to identify the components of synthetic QMP required for the anti-ovarian effect. We found that virgin females respond strongly to 9-oxo-2-decenoic acid and 10-hydroxy-2-decenoic acid (10HDA), suggesting that the decenoic acid components of QMP are essential for the anti-ovarian response. Further, a nuclear factor of activated T-cells reporter system revealed neurones expressing the olfactory receptors Or-56a, Or-49b and Or-98a are activated by QMP in the antenna. In addition, we used olfactory receptor GAL4 drivers and a neuronal activator (a neuronal activating bacterial sodium channel) to test whether the candidate neurones are potential labelled lines for a decenoic acid response. We identified Or-49b as a potential candidate receiver of the 10HDA signal. Finally, the anti-ovarian response to synthetic QMP is not mediated by decreasing the titre of the reproductive hormones ecdysone and juvenile hormone.

Popliteal artery entrapment syndrome is an uncommon cause of peripheral vascular disease in young fit individuals, presenting as progressive claudication or sudden limb ischaemia. It can also present later in life with insidious symptoms relating to popliteal thrombosis or aneurysm. As a local cause of atherosclerosis in the popliteal artery it is probably under-diagnosed, as clinical and radiological features are subtle and varied. Early diagnosis and surgical division of aberrant muscular relations result in an excellent clinical result. Late surgical treatment with vein grafting is less durable. The disease incidence, clinical features, pathology, investigations, treatment and prognosis are reviewed.

Radiation accidents outside of the nuclear sector account for a significant pro­ portion of fatal and non-fatal radiation accidents. Relevant statistics are briefly reviewed and then the paper concentrates on one of the most serious radiologi­ cal accidents, that in Goiânia, Brazil, in 1987. In that accident four people died and there was significant spread of radioactive contamination from a ruptured radiotherapy source. The development of the accident, the response to it and the lessons learned from it are addressed.

The GridPP Collaboration is building a UK computing Grid for particle physics, as part of the international effort towards computing for the Large Hadron Collider. The project, funded by the UK Particle Physics and Astronomy Research Council (PPARC), began in September 2001 and completed its first phase 3 years later. GridPP is a collaboration of approximately 100 researchers in 19 UK university particle physics groups, the Council for the Central Laboratory of the Research Councils and CERN, reflecting the strategic importance of the project. In collaboration with other European and US efforts, the first phase of the project demonstrated the feasibility of developing, deploying and operating a Grid-based computing system to meet the UK needs of the Large Hadron Collider experiments. This note describes the work undertaken to achieve this goal. © 2006 IOP Publishing Ltd.

Electrooculogram (EOG) correction is used to remove eye-movement-related contamination from electroencephalograms (EEG). Correction is reliant on the regression procedure, although when multiple EOG channels are used in the correction, the appropriate type of regression to use is not known. In the present study, we aimed to resolve this matter. Computer simulations were used to compare the simultaneous, multiple-stage, and single-channel regression methods of correction. EOG propagation was modeled on prior findings, under conditions of varying vertical and horizontal EOG (VEOG/HEOG) correlation. The dependent variable was the correlation between the uncontaminated and the corrected EEG. The simultaneous regression procedure gave the best correction, with its advantage increasing as a function of VEOG/HEOG correlation. It is recommended that the simultaneous regression procedure be used for EOG correction of the EEG.

A case is described of a neurilemmoma of the first thoracic nerve. Its presentation as a Horner's syndrome in combination with thoracic outlet syndrome is unique.

Le principe d’optimisation repose sur l’idee de maintenir les expositions “aussi bas qu’il est raisonnablement possible” (principe ALARA). Afin de mettre en œuvre ce principe, la Commission internationale de protection radiologique (CIPR) a recommande l’utilisation de l'analyse cout-benefice. Alors que cette methode d’aide a la decision est maintenant largement appliquee dans le domaine industriel et nucleaire, elle n’a recu que peu d'echos dans le secteur medical, bien qu’en ce domaine il existe un potentiel pour une reduction des doses, et en particulier celles recues par les patients. Cet article a pour objectif d'attirer l’attention sur les applications possibles de l’optimisation dans le secteur medical, en rappelant les solutions particulieres proposees en Grande-Bretagne pour la valorisation monetaire de l’homme-sievert ainsi que pour l'application de l'analyse cout-benefice. Bien que faisant reference au contexte de la Grande-Bretagne en matiere de reglementation et de pratiques medicales, les principes fondamentaux decrits dans cet article peuvent etre appliques a d’autres pays.

This paper focuses on how the ALARA concept can be practically implemented in operational situations and in particular on the value of using a structured approach and the problem of the collection of relevant dosimetric data. The roles of ALARA audits, quantitative decision aiding techniques and predictive ALARA plans are discussed and some practical examples provided. A basic requirement in the pursuance of optimisation is to be able to quantify the doses predicted to be associated with the various components of a person's work. Many dosimetric systems in use simply cannot provide these data and the need to provide task specific dosimetry with a feedback mechanism into dose modelling is discussed.

SUMMARYDiets containing 10·5, 13, 15·5 or 18% protein were formulated by progressively replacing barley by a 2:1 mixture of soya-bean meal and fish meal. Each diet was given at three levels of intake proportional to (body weight) 0·73. A total of 144 pigs were used at two centres.Growth rate increased with food intake at each protein level, but to the greatest extent with the 13% crude protein (CP) diet. Growth rate also increased with protein level; the results suggested that there would be no further improvement above 18% CP. The effects of protein concentrationon food conversion generally reflected those on daily gain.Carcass fatness, estimated by both midline and introscope measurements of fat thickness and by specific gravity, increased significantly with the intake of all but the 18% protein diet. When theeffects of food intake were taken into account, carcass fatness increased steadily with reductions in protein level down to 13%; the reduction from 13 to 10·5% produced a much greaterincrease in fatness.The reductions in daily food intake necessary to achieve equal carcass fatness as protein level wasreduced were of the order of 0·1 kg per 1% CP from 18% to 13% CP, but ofthe order of 0·3 kg per 1% CP below 13%.Differences between the sexes were greatest at high protein concentration; significant differences between the centres were found only with the low protein diets.

SUMMARY1. In a comparative slaughter experiment, 12 female pigs (six at 80 kg and six at 100 kg) were allocated at first oestrus to each of five treatments: Treatment 1 initial slaughter, or Treatments 2, 3 and 4 mated and given 19·5, 25·8 or 32·1 MJ ME/day for the last 100 days of pregnancy, or Treatment 5 not mated (virgin) and given 25·8 MJ ME/day over a similar period. Pigs on Treatments 2, 3, 4 and 5 were given the same amount of protein and were killed about 123 days after first oestrus. Piglets were removed at birth.2. Total protein deposition (carcass+viscera+piglets) was increased from a total (±SE) of 5·50 to 8·47 (±0·43) kg as ME intake was increased from 19·5 to 32·1 MJ ME/day. About 75% of the increase in protein deposition was in the carcass component. The average response to ME was 2·2 ± 0·58 g total protein deposition per MJ increment in ME.3. The once-mated pigs deposited similar amounts of total protein to the virgin pigs but significantly less (P4. Increasing energy intake from 19·5 to 32·1 MJ ME/day increased total fat deposition from 2·8 to 16·0 kg. The average response to ME was 13·5 ± 1·53 g fat deposited per MJ increment in ME.5. There were no significant differences between the once-mated and virgin pigs in their calculated maintenance requirement, nor in the efficiency with which ME surplus to requirement for maintenance was utilized for energy retention. The average maintenance requirement for all pigs was 530 (95% limits 303·882) kJ/kg0·85. day. The average efficiency of utilization of ME for energy retention was 58·5 ± 6·2%.6. There was no evidence of any pregnancy anabolism other than that involving the conceptus, the needs of the dam specific to pregnancy and preparation for lactation.

SummaryCircadian variation in the apparent digestibility of diets having different physical characteristics was measured in samples taken from the terminal ileum using simple cannulae and marker ratios. Six pigs were used in three latin squares involving three iso-nitrogenous diets (30 g N/kg D.M.). Diet A was based on barley, weatings, soyabean meal and fish meal, diet B included barley, weatings and oats and diet C was purified. The allocation of diet provided 100 g D.M./kg Weg0·75/24 h and in each latin square a different pattern of feed intake was used; diets were given at intervals of either 1 or 12 h, or ad libitum.Differences in the digestibility of the diets were consistently distinguished by the technique. The circadian variation in digestibility was related to the type of diet and could be modified by changing the number and distribution of feeds per day. The results show that an understanding of the variation associated with different diets and feeding methods is necessary for optimizing the strategy for sampling from the terminal ileum.

1. Thirty-three diets were made by adding to ground barley combinations of L-lysine (0–6.0 g/kg) and L-threonine (0–3.0 g/kg), together with vitamins and minerals. Each was given to two female and two castrated male pigs during their growth from 25 to 60 kg.2. Growth rate increased from 0.36 kg/d to a maximum of 0.65 kg/d with additions of 3.8 g L-lysine/kg and 1.8 g L-threonine/kg; these values and the maximum gains achieved were slightly higher for castrates than for females. Minimum values for food conversion ratio of 2.84 for castrates and 3.06 for females were achieved with similar amino acid additions to those giving fastest growth.3. Carcass fat, estimated by specific gravity, was least with the addition of 5.9 g L-lysine/kg, but continued to decrease up to the highest threonine concentrations. Backfat thickness was also reduced by amino acid additions but failed to reach a minimum.

For pt.I, see ibid., vol.1, no.2, p.15, (1981). An exercise is described in which the objectives are to illustrate some of the problems and underlying principles related to scattered radiation in industrial radiography situations, although the principles involved can be applied to other situations. A model of a radiography room, with a beta emitter as the source of radiation, is used to demonstrate: the scatter of radiation down a maze entrance; 'air scatter' over the walls of the room; the effect of beam collimation on dose rates from scattered radiation; the minimisation of scattered dose rates by judicious direction of the collimated beam. The exercise is strictly qualitative and course participants are positively warned that the results must not be regarded as having any quantitative value. The exercise provokes discussions on a number of topics; typically regarding the economic benefit (in terms of savings in cost of protection) to be derived from being able to limit the size and direction of the useful beam.

The nitrogen (N) of raw potato is poorly digested by the pig and the hypothesis tested in the experiment was that this is due to an anti-nutritive substance present in the tuber and not simply due to the physical inaccessibility of much of the potato protein to enzyme attack or to the protein of the potato being refractory to gut enzymes. Four growing pigs, each fitted with an ileal cannula were fed on a basal diet of barley plus minerals and vitamins to which was added minced raw potato (RP) or a liquid extract of potatoes which was either freeze-dried (LE) or boiled and concentrated (BE). These materials each contributed 12 g N day−1 for each pig. Each pig was given 2.1 kg organic matter (OM) day−1. In diet RP 25.5% of this was from potato compared with 7.2 and 7.8% in diets LE and BE, respectively. The digestibility of N determined at the terminal ileum was reduced with RP by 9.5% (NS) and with LE by 23% (P

SUMMARY1. In a comparative slaughter experiment, 12 female pigs (six at 80 kg and six at 100 kg) were allocated at first oestrus to each of five treatments: Treatment 1, initial slaughter, or Treatments 2, 3 and 4, mated and given 19·5, 25·8 or 32·1 MJ ME/day for the last 100 days of pregnancy, or Treatment 5, not mated (virgin) and given 25·8 MJ ME/day over a similar period. Pigs on Treatments 2, 3, 4 and 5 were given the same amount of protein and were killed about 123 days after first oestrus. Piglets were removed at birth.2. There was no evidence of any special effect of pregnancy in the stimulation of permanent maternal growth. The average live weight, ingesta-free body and carcass gains of the pair-fed, mated and virgin gilts (±SE of difference) were, respectively, 32·3 and 36·9 + 2·8, 27·5 and 27·6 ± 3·4, and 26·0 and 26·7 + 2·1 kg. There were no statistically significant differences between these two treatments in carcass composition, specific gravity or backfat thickness. The mated pigs had lighter livers (P < 0·01) and heavier reproductive tracts (P < 0·05), and lost about 9 kg within a week of parturition.3. Increasing energy intake increased piglet birth weights (Pv. 80 kg) had 1·5 more piglets, though this was not statistically significant (P4. Although there was no special effect of pregnancy on permanent maternal growth, the conversion of food by the once-mated pig was very efficient if an allowance was made for the food cost of producing the piglets.