Colored Spin Systems, BKP Evolution and finite N_c effects

Even within the framework of the leading logarithmic approximation the eigenvalues of the BKP kernel for states of more than three reggeized gluons are unknown in general, contrary to the planar limit case where the problem becomes integrable. We consider a 4-gluon kernel for a finite number of colors and define some simple toy models for the configuration space dynamics, which are directly solvable with group theoretical methods. Then we study the dependence of the spectrum of these models with respect to the number of colors and make comparisons with the large limit case.Comment: 17 pages, 4 figures, references update, to appear on EPJ

Impact on Prehospital Delay of a Stroke Preparedness Campaign: A SW-RCT (Stepped-Wedge Cluster Randomized Controlled Trial)

Background and Purpose—Public campaigns to increase stroke preparedness have been tested in different contexts, showing contradictory results. We evaluated the effectiveness of a stroke campaign, designed specifically for the Italian population in reducing prehospital delay. Methods—According to an SW-RCT (Stepped-Wedge Cluster Randomized Controlled Trial) design, the campaign was launched in 4 provinces in the northern part of the region Emilia Romagna at 3-month intervals in randomized sequence. The units of analysis were the patients admitted to hospital, with stroke and transient ischemic attack, over a time period of 15 months, beginning 3 months before the intervention was launched in the first province to allow for baseline data collection. The proportion of early arrivals (within 2 hours of symptom onset) was the primary outcome. Thrombolysis rate and some behavioral end points were the secondary outcomes. Data were analyzed using a fixed-effect model, adjusting for cluster and time trends. Results—We enrolled 1622 patients, 912 exposed and 710 nonexposed to the campaign. The proportion of early access was nonsignificantly lower in exposed patients (354 [38.8%] versus 315 [44.4%]; adjusted odds ratio, 0.81; 95% confidence interval, 0.60–1.08; P=0.15). As for secondary end points, an increase was found for stroke recognition, which approximated but did not reach statistical significance (P=0.07). Conclusions—Our campaign was not effective in reducing prehospital delay. Even if some limitations of the intervention, mainly in terms of duration, are taken into account, our study demonstrates that new communication strategies should be tested before large-scale implementation. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT01881152

Small x QCD and multigluon states: A Color toy model

We introduce and study a toy model with a finite number of degrees of freedom whose Hamiltonian presents the same color structure of the BKP system appearing in the studies of QCD in the Regge limit. We address within this toy model the question of the importance of finite number of color corrections with respect to the planar limit case

Analysis of fatty acid steryl esters in tetraploid and hexaploids wheats: identification and comparison between chromatographic methods

Steryl esters with fatty acid obtained from 14 genotypes of tetraploid (T. dicoccon and T. durum) and 17 genotypes of hexaploid (T. spelta and T. aestivum) wheats were analysed using different chromatographic strategies. GC-FID and HPLC-ELSD analysis of non-hydrolysed SE indicated major differences between the tetraploid and hexaploid species, the latter being qualitatively and quantitatively rich in this class of compounds. The hydrolysed SE injected into GC confirmed the differences between the classes of tetraploid wheats, where palmitic acid was not detectable, and hexaploid wheats, where traces of oleic acid were found. The distribution of the steryl residues between both classes of wheat did not differ. Lastly, the HPLC method hyphenated to ESI-MS detection enabled SE to be recognised by the characteristic fragmentations and ion-adducts of each molecule. In particular, minor traces of campesteryl and sitosteryl and practically no trace of stigmasteryl palmitates were found in T. durum and its hulled ancestor T. dicoccon, while steryl oleates were not detectable (the minimum amount detectable being 0.02mg/100g d.b.) in T. aestivum and its hulled ancestor T. spelta, which is consistent with the filogenesis of tetraploid and hexaploid wheat species. Steryl linoleates and linolenates were found to be equally distributed in both tetraploid and hexaploid wheats