Interaction Strengths for the Fock-Space Formulation of the Nuclear Pairing Problem

A realistic nuclear mean-field hamiltonian with pairing has been diagonalized using Fock space representation that allows for nearly exact treatment of the problem. Calculations were performed for all the even-even nuclei with Z in (20, 100), whose pairing gaps were possible to extract out of the experimental masses. The optimal values of the pairing strength constants for the protons and neutrons have been found.Comment: Seminar given at XXXVII School of Physics in Zakopane, Poland. Paper in LaTeX, 4 pages including one figure, submitted to Acta Physica Polonica

Validation of differential pulse polarographic method of ascorbic acid assay in food – Comparison with the chromatographic reference method

The objective of the study was to demonstrate the applicability of differential pulse polarography (DPP) technique of the ascorbic acid (AA) assay for the analysis of food samples with various matrices. The following validation parameters were determined: selectivity, linearity, precision, accuracy, limit of detection, and limit of quantification. The limits of detection and quantification were 0.17 and 0.5 mg ascorbic acid per 100 g food, respectively. The average recovery of added ascorbic acid from all matrices was 96.3–103.6%. The values of the coefficient of variation calculated on the basis of AA contents for food matrices were in the range 2–9.26% and Horrat values were 0.37–1.10. Ascorbic acid values of the samples obtained from the polarographic method were compared with those obtained from high-performance liquid chromatography with diode-array detection (HPLC-DAD) used as the reference method. The analytical parameters determined showed that the polarographic method was equivalent to the chromatographic method. Validation of the polarographic method of ascorbic acid assay indicates that it can be applied for the analysis of ascorbic acid concentration in food products that do not contain isoascorbic acid. This means that the method can be recommended for routine determinations

On farm welfare assessment of beef cattle using an environmentally-based welfare index and investigation of the human-animal relationship.

End of Project ReportStudy 1. Animal welfare index (AWI): an on-farm survey of beef suckler farms in Ireland Summary The objectives were to (i) examine the welfare status of Irish beef suckler herds using an animal welfare index (AWI) adapted from a previously validated welfare assessment method (TGI); (ii) determine the influence of the stockpersons’ status (full: FT or part-time: PT), their interest in farming and herd size on the AWI; and (iii) compare the AWI with the TGI. Beef suckler farms (196 throughout 13 counties) were assessed once with housed cattle and once with cattle at grass using the AWI. Twenty-three of the 196 farms were revisited a year after using the AWI and the TGI. Thirty-three indicators were collected in five categories: locomotion (5 indicators); social interactions (7), flooring (5), environment (7) and stockpersonship (9). Three indicators relating to the size of the farm were also collected. The mean AWI was 65% and ranged from 54% to 83%. The grass period represented 16.5% of mean total points of the AWI. Seventy percent of the farms were rated as “Very Good” or “Excellent”. There was no difference (P > 0.05) in AWI between FT and PT farmers. PT farmers had greater (P = 0.01) “social interactions”: calving (P = 0.03) and weaning (P < 0.001) scores. FT farmers had cleaner animals (P = 0.03) and less lameness (P = 0.01). The number of animals and the interest of the stockperson were negatively and positively correlated (P = 0.001), respectively, with the AWI. A hierarchical classification was performed to examine how the indicators influenced the AWI. Farms could be categorized into three classes, the most discriminating factors for the classes were the interest of the farmer (higher scores when the farmer was more interested in farming) and the number of animals (higher scores when the herds were smaller). Study 2. Investigation and specificity of behavioural fear responses of heifers to different fear-eliciting situations involving humans. Summary This study investigated the specificity of fear responses in housed beef heifers’ over time using four behavioural tests; flight, docility, fear and chute tests. The flight, (time to join peers and avoidance distance), docility (isolation and handling) and fear (4 phases; responses of isolated heifers in (i), the absence (ii), the presence, of food and responses to a stationary human (iii) without and (iv) with visual contact of their peers) tests were carried out over three consecutive days, in that order, commencing on day 30 and again on day 80 post-housing. The chute test (movement through a race and agitation of heifers during blood sampling) was performed on day 84 post-housing. Scores (higher scores meant less fearful animals) were assigned to the fear responses. Heifers had the lowest (P < 0.05) scores during phases (i) and (iii) of the fear test and the highest (P< 0.05) during phase (iv). The most docile heifers during the docility test were the most agitated during the chute test (P < 0.001). The fear scores were sTable over time for the docility test but decreased for the fear test. The fear scores when restrained (chute test) were not correlated with other scores except for the agitation. A PCA showed that two components (avoidance of stimulus and general agitation explained 49% of the total variation. In conclusion, this study showed that fear responses of heifers can vary over time and that fear is not unitary but multidimensional. Consequently, fear responses are condition specific and tests assessing fear should consider their specificity.European Union Structural Funds (EAGGF

Sequential fissions of heavy nuclear systems

In Xe+Sn central collisions from 12 to 20 MeV/A measured with the INDRA 4$\pi$ multidetector, the three-fragment exit channel occurs with a significant cross section. In this contribution, we show that these fragments arise from two successive binary splittings of a heavy composite system. Strong Coulomb proximity effects are observed in the three-fragment final state. By comparison with Coulomb trajectory calculations, we show that the time scale between the consecutive break-ups decreases with increasing bombarding energy, becoming compatible with quasi-simultaneous multifragmentation above 18 MeV/A.Comment: 6 pages, 5 figures, contribution to conference proceedings of the Fifth International Workshop on Nuclear fission and Fission-Product Spectroscop