1,125 research outputs found
Strangeness Production in pp,pA,AA Interactions at SPS Energies.HIJING Approach
In this report we have made a systematic study of strangeness production in
proton-proton(pp),proton-nucleus(pA) and nucleus- nucleus(AA) collisions at
CERN Super Proton Synchroton energies, using \\ (version ). Numerical results for mean
multiplicities of neutral strange particles ,as well as their ratios to
negatives hadrons() for
p-p,nucleon-nucleon(N-N),\,\,p-S,\,\,p-Ag,\,\,p-Au('min. bias')collisions and
p-Au,\,\,S-S,\,\,S-Ag,\,\,S-Au ('central')collisions are compared to
experimental data available from CERN experiments and also with recent
theoretical estimations given by others models. Neutral strange particle
abundances are quite well described for p-p,N-N and p-A interactions ,but are
underpredicted by a factor of two in A-A interactions for
in symmetric collisions(S-S,\,\,Pb-Pb)and for
in asymmetric ones(S-Ag,\,\,S-Au,\,\,S-W). A
qualitative prediction for rapidity, transverse kinetic energy and transverse
momenta normalized distributions are performed at 200 GeV/Nucleon in
p-S,S-S,S-Ag and S-Au collisions in comparison with recent experimental data.
HIJING model predictions for coming experiments at CERN for S-Au, S-W and Pb-Pb
interactions are given. The theoretical calculations are estimated in a full
phase space.Comment: 33 pages(LATEX),18 figures not included,available in hard copy upon
request , Dipartamento di Fisica Padova,report DFPD-94-NP-4
1H NMR metabolic profile to discriminate pasture based alpine asiago PDO cheeses
The study was carried out in an alpine area of North-Eastern Italy to assess the reliability of proton nuclear magnetic resonance 1H NMR to fingerprint and discriminate Asiago PDO cheeses processed in the same dairy plant from upland pasture-based milk or from upland hay-based milk. Six experimental types of Asiago cheese were made from raw milk considering 2 cows’ feeding systems (pasture- vs. hay-based milk) and 3 ripening times (2 months, Pressato vs. 4 months, Allevo_4 vs. 6 months, Allevo_6). Samples (n = 55) were submitted to chemical analysis and to 1HNMRcoupled with multivariate canonical discriminant analysis. Choline, 2,3-butanediol, lysine, tyrosine, and some signals of sugar-like compounds were suggested as the main water-soluble metabolites useful to discriminate cheese according to cows’ feeding system. A wider pool of polar biomarkers explained the variation due to ripening time. The validation procedure based on a predictive set suggested that 1H NMR based metabolomics was an effective fingerprinting tool to identify pasture-based cheese samples with the shortest ripening period (Pressato). The classification to the actual feeding system of more aged cheese samples was less accurate likely due to their chemical and biochemical changes induced by a prolonged maturation process
Deviation of behavioural and productive parameters in dairy cows due to a lameness event: a synthesis of reviews
Lameness is a widespread multifactorial condition affecting the health and performance of dairy cows. Despite the growing support by precision farming technologies, farmers still lack reliable data-driven tools to early identify lame cows. This study used a synthesis of reviews to identify cow’s behavioural and productive parameters most related to lameness and estimate their deviation due to a lameness event. The methodological approach used reviews as starting point to identify the most pertinent studies with the intention of extracting and analysing data from these primary studies. The final dataset used information collected from 31 research papers, cited in 15 reviews, and involved more than 25,000 dairy cows. Five parameters were suitable for the meta-analysis: one about eating behaviour (eating time), three regarding activity and resting behaviour (lying bouts, lying bout duration and lying time) and milk yield. The meta-analysis revealed that all parameters had a significant deviation in cows affected by lameness. The calculation of the pooled means allowed to quantify a mean value for the deviation imposed by a severe lameness event from the value recorded on nonlame cows. Compared to a nonlame animal, a lame cow had a significant negative deviation for eating time (−39 min/day), number of lying bouts (−0.5/day), and milk yield (−3 kg/day). Lame cows had positive deviations for lying bout duration (+12 min/bout) and daily lying time (+42 min/day). The individual or combined use of these mean deviation values as alarm reference thresholds could improve the accuracy of the current automated lameness detection systems
Effect of decreasing dietary crude protein on growth performance, feed efficiency and meat quality of finishing Charolais bulls
This study aimed to evaluate the effect of decreasing dietary crude protein (CP) on the performance of finishing Charolais bulls in the Italian rearing system. Animals were fed two diets, differing only in the CP level (low protein (LP), 13.5% CP versus control (CON), 15.0% CP). Dry matter (DM) intake (DMI) and animals\u2019 weights were recorded to obtain average daily gain (ADG) and feed conversion rate (FCR). Feed and fecal samples were collected to evaluate digestibility of diet components. Daily cost of the ration (DRC), feed cost per kg of daily weight gain (CDG) and daily gross margin (DGM) were calculated to analyze the possible benefits of decreasing the protein level. Meat quality analyses were also conducted. Higher DMI (10.6 versus 10 kg/d; p < 0.05) and ADG (1.47 versus 1.36 kg/d; p < 0.05) were observed for CON. No differences in FCR or digestibility were found. Even if the DRC was lower (p < 0.05) for the LP diet (2.26 versus 1.97 \u20ac; CON versus LP), no difference was reported for CDG and DGM. Meat lightness and redness were significantly lower and higher in the LP, respectively. To conclude, the CP requirement in these rearing conditions appeared to be higher than 13.5%
Influence of Ageing Time and Method on Beef Quality and Safety
The effectiveness of dry ageing with regard to retaining meat quality is still subject to debate. At 4 d post mortem, samples of boneless strip loins were excised from young Charolais carcasses and then stored for a further 26 d in a cooler, either vacuum-packaged (VP) or dried-aged (DA). Loin samples were also dissected 7 d post mortem as a control treatment (CT). Chemical, instrumental and microbiological data (n = 18) were determined in longissimus dorsi and underwent ANOVA to estimate the differences in the ageing fixed factor split into two orthogonal contrasts: control vs. aged and VP vs. DA. Ageing loss (both surface dehydration and water purge) was greater in DA compared to VP samples, resulting in the lowest moisture content and highest crude protein and fat percentage in DA loins. The ageing method did not affect meat surface colour, except for redness, which had the lowest value in DA samples. Meat tenderness improved a similar amount following both VP and DA ageing treatments. Compared to the control, prolonged ageing raised both the peroxide value and the total microbial count, especially in DA samples, though both remained within the recommended limits. In summation, both ageing methods improved beef meat tenderisation, preserving its shelf life
The Role of Spleen and Liver Elastography and Color-Doppler Ultrasound in the Assessment of Transjugular Intrahepatic Portosystemic Shunt Function
The reference standard for assessing transjugular intrahepatic portosystemic shunt (TIPS) function is venography with portosystemic pressure gradient (PPG) measurement. This procedure is invasive and expensive; thus, we assessed the feasibility, reproducibility and diagnostic accuracy of color-Doppler ultrasound (CDUS) and spleen and liver stiffness (LS) measurements for identifying TIPS dysfunction. Twenty-four patients (15 undergoing TIPS placement and nine undergoing TIPS revision) consecutively underwent CDUS examination and LS and spleen stiffness (SS) determination by transient elastography (TE) and point shear-wave elastography (pSWE). All parameters were taken before TIPS placement/revision (1\u201315 d before) and 24 h after, just before revision by venography. pSWE inter-observer agreement was assessed by intra-class correlation coefficient (ICC). CDUS and elastographic data were correlated (Pearson coefficient) with pressure gradients (hepatic venous pressure gradient [HVPG], PPG). Main determinants of TIPS dysfunction were investigated by linear regression. Forty-nine paired examinations were performed in total: 49 (100%) SS reliable measurements by pSWE and 38 (88%) by TE. The ICC for pSWE values was 0.90 (95% confidence interval [CI] 0.81\u20120.94). SS values significantly correlated with HVPG and PPG (R = 0.51, p = 0.01). The area under the Receiver-Operating Characteristic (AUROC) curve of SS for diagnosing TIPS dysfunction was 0.86 (95% CI 0.70\u20120.96) using a 25 kPa cutoff. At multivariate analysis, the flow direction of the intrahepatic portal vein branches and SS values were independently associated to TIPS dysfunction. The intrahepatic portal vein branches flow direction and SS value are two simple, highly sensitive parameters accurately excluding TIPS dysfunction. SS measurement by pSWE is feasible, reproducible and both positively and significantly correlates with HVPG and PPG values
Performance of ALICE pixel prototypes in high energy beams
The two innermost layers of the ALICE inner tracking system are instrumented
with silicon pixel detectors. Single chip assembly prototypes of the ALICE
pixels have been tested in high energy particle beams at the CERN SPS.
Detection efficiency and spatial precision have been studied as a function of
the threshold and the track incidence angle. The experimental method, data
analysis and main results are presented.Comment: 10 pages, 9 figures, contribution to PIX2005 Workshop, Bonn
(Germany), 5-8 September 200
Beam Test Performance and Simulation of Prototypes for the ALICE Silicon Pixel Detector
The silicon pixel detector (SPD) of the ALICE experiment in preparation at
the Large Hadron Collider (LHC) at CERN is designed to provide the precise
vertex reconstruction needed for measuring heavy flavor production in heavy ion
collisions at very high energies and high multiplicity. The SPD forms the
innermost part of the Inner Tracking System (ITS) which also includes silicon
drift and silicon strip detectors. Single assembly prototypes of the ALICE SPD
have been tested at the CERN SPS using high energy proton/pion beams in 2002
and 2003. We report on the experimental determination of the spatial precision.
We also report on the first combined beam test with prototypes of the other ITS
silicon detector technologies at the CERN SPS in November 2004. The issue of
SPD simulation is briefly discussed.Comment: 4 pages, 5 figures, prepared for proceedings of 7th International
Position Sensitive Detectors Conference, Liverpool, Sept. 200
81 Infections after allogeneic bone marrow transplantation (allo-BMT) in South Brazil: Low incidence of invasive fungal infections despite low-dose fluconazole prophylaxis
Centrality dependence of the expansion dynamics in Pb-Pb collisions at 158 A GeV/c
Two-particle correlation functions of negatively charged hadrons from Pb-Pb
collisions at 158 GeV/c per nucleon have been measured by the WA97 experiment
at the CERN SPS. A Coulomb correction procedure that assumes an expanding
source has been implemented. Within the framework of an expanding thermalized
source model the size and dynamical state of the collision fireball at
freeze-out have been reconstructed as a function of the centrality of the
collision. Less central collisions exhibit a different dynamics than central
ones: both transverse and longitudinal expansion velocities are slower, the
expansion duration is shorter and the system freezes out showing smaller
dimensions and higher temperature.Comment: 22 pages, 11 figures, Te
- …