2,341 research outputs found
Preference inference based on Pareto models
In this paper, we consider Preference Inference based on a generalised form of Pareto order. Preference Inference aims at reasoning over an incomplete specification of user preferences. We focus on two problems. The Preference Deduction Problem (PDP) asks if another preference statement can be deduced (with certainty) from a set of given preference statements. The Preference Consistency Problem (PCP) asks if a set of given preference statements is consistent, i.e., the statements are not contradicting each other. Here, preference statements are direct comparisons between alternatives (strict and non-strict). It is assumed that a set of evaluation functions is known by which all alternatives can be rated. We consider Pareto models which induce order relations on the set of alternatives in a Pareto manner, i.e., one alternative is preferred to another only if it is preferred on every component of the model. We describe characterisations for deduction and consistency based on an analysis of the set of evaluation functions, and present algorithmic solutions and complexity results for PDP and PCP, based on Pareto models in general and for a special case. Furthermore, a comparison shows that the inference based on Pareto models is less cautious than some other types of well-known preference model
La métaplasie malpighienne dans le carcinome papillaire de la thyroïde
Introduction : la métaplasie malpighienne est rare au niveau de la thyroïde. Elle peut être associée à un processus pathologique tumoral ou inflammatoire.Matériels et méthodes : les auteurs se proposent de rapporter une observation de métaplasie malpighienne de la thyroïde associée à un carcinome papillaire diagnostiqué au service d’Anatomie et de Cytologie pathologiques du CHU Farhat Hached de Sousse et d’en discuter la pathogénie de cette métaplasie, ses circonstances de survenue et ses difficultés diagnostiques.Résultats : il s’agissait d’une fille âgée de 9 ans ayant consulté pour un nodule de la thyroïde. Une cytoponction de ce nodule était pratiquée et avait montré la présence de cellules tumorales d’un carcinome papillaire. Une thyroïdectomie totale avec curage triangulaire fonctionnel a été réalisée. L’examen anatomo-pathologique de la pièce a confirmé la présence d’un carcinome papillaire de la thyroïde avec présence au voisinage de la tumeur de plages de cellules malpighiennes d’allure non tumorale.Conclusion : bien que rare, la métaplasie malpighienne peut se voir dans la thyroïde. Elle doit être distinguée d’un carcinome épidermoïde de la thyroïde par la recherche systématique, devant tout foyer de métaplasie malpighienne, des signes de malignité.Mots clés : métaplasie malpighienne, carcinome papillaire, glande thyroïde
Longer nap duration during Ramadan observance positively impacts 5-m shuttle run test performance performed in the afternoon
It is well-documented that changes in the rhythm of life during Ramadan affect sleep schedules (i.e., interruption of night sleep patterns) and are likely to have negative effects on physical and cognitive performances. The aim of the present study was to examine the effect of different naps opportunities’ durations during Ramadan on performance of short-duration repetitive maximal exercise and perception of effort. Fifteen physically active men (age: 21 ± 3 years, height: 177 ± 6 cm, body-mass: 73 ± 10 kg) performed a 6 × 30-s shuttle run test after a 25-min nap (N25), a 45-min nap (N45), and in a no-nap condition (NN) during three experimental periods: ∼2 weeks before Ramadan (BR), the last ten days of Ramadan (ER), and ∼3 weeks after Ramadan (AR). During the shuttle run test performed in the late afternoon, the greatest distance (GD), the total distance (TD) and a fatigue index (FI) were assessed. Rating of perceived exertion (RPE) was determined after each 30-s effort. Dietary intake and sleep quality were assessed in each of the three periods. Compared to BR, GD and TD were lower in the ER testing period (p = 0.005; d = 0.54) but returned to BR levels in the AR period. During ER, carbohydrate intake was lower (p = 0.04; d = 0.2), and sleep duration and sleep quality were reduced (d = 0.27 and 0.54, respectively), although other aspects of dietary intake and sleep pattern were not affected. Compared to NN, GD and TD were higher after N25 (d = 0.57 and 0.34, respectively) and N45 (d = 0.93 and 0.88 respectively). RPE was lower in N45 (p = 0.035, d = 0.84). N45 resulted in higher TD (p = 0.021, d = 0.13) and lower RPE (p = 0.004; d = 0.57) compared to N25 during ER. Taking a daytime nap benefits subsequent performance in a shuttle run test, whether sleep the previous night was normal (as in BR) or compromised (as in ER). The benefits of napping were greater after a 45-min nap opportunity than after a 25-min nap opportunity
Cambios en la composición proximal y en las características de los aceites durante el desarrollo de semillas de linaza
Atmospheric Pressure Photoionization-Mass Spectrometry (APPI-MS) and High Performance Liquid Chromatography (HPLC) are the two analytical methods that were used to characterize Triacylglycerols (TAGs) during flaxseed development. The HPLC method of the oils showed the presence of 15 TAG species. In contrast to the HPLC chromatograms, the APPI-MS showed 17 peaks of TAG. APPI-MS is more rapid than the HPLC method (11 min). The iodine value of the oils showed a gradual increase, while the oil stability continuously decreased. Proximate composition during flaxseed development revealed that flaxseed is potentially a good source of dietary energy and protein. At full maturity, flaxseed contained 37% oil and 24% protein on a dry-weight basis; albumin was the major storage protein (53% of total storage proteins) followed by globulin (33%) and glutelin fractions (11%). Prolamins had the lowest percentage with 3%. α-amylase activity was higher in the mature seeds than the young ones.Fotoionización a presión atmosférica-Espectrometría de masas (APPI-MS) y cromatografía líquida de alta resolución (HPLC) son dos métodos de análisis que se utilizaron para caracterizar triglicéridos (TAGs) durante el desarrollo de semillas de linaza. El método HPLC mostró la presencia de 15 especies de TAG, en contraste, los cromatogramas de APPI-MS mostraron 17 picos de TAG siendo el método APPI-MS más rápido que el de HPLC (11 min). El índice de yodo de los aceites mostró un aumento gradual, mientras que la estabilidad disminuyó continuamente. El estudio de la composición proximal de la linaza durante su desarrollo, mostró que esta semilla es una fuente potencialmente buena de energía y de proteína para la dieta. Al final de la maduración, la linaza contenía 37 % de aceite y 24 % de proteína sobre peso seco; albúmina fue la principal proteína de almacenamiento (53% sobre el total de las proteínas de almacenamiento) seguido de la globulina (33 %) y glutelina (11 %). Las prolaminas presentaron el porcentaje más bajo con 3 %. La actividad α-amilasa fue mayor en las semillas maduras que en las más jóvenes
Search for the b --> d gamma process
We report the results of a search for the flavor-changing neutral current
process b --> d gamma using a sample of 275 million B meson pairs accumulated
by the Belle detector at KEKB. We find no significant signal for the exclusive
decays B- --> rho- gamma, B0B --> rho0 gamma, or B0B --> omega gamma. Assuming
an isospin relation between the three modes, we set an upper limit for the
combined branching fraction Br(B --> (rho,omega) gamma) < 1.4 x 10-6 at the 90%
confidence level. This limit can be used to constrain the ratio of CKM matrix
elements |Vtd/Vts|.Comment: 6 pages, 2 figures, submitted to Phys. Rev. D (RC
Observation of B+ -> Dbar*0 tau+ nu_tau and Evidence for B+ -> Dbar^0 tau+ nu_tau at Belle
We present measurements of B+ -> Dbar*0 tau+ nu_tau and B+ -> Dbar^0 tau+
nu_tau decays in a data sample of 657 x 10^6 BBbar pairs collected with the
Belle detector at the KEKB asymmetric-energy e+e- collider. We find
446^{+58}_{-56} events of the decay B+ -> Dbar*0 tau+ nu_tau with a
significance of 8.1 standard deviations, and 146^{+42}_{-41} events of the
decay B+ -> Dbar0 tau+ nu_tau with a significance of 3.5 standard deviations.
The latter signal provides the first evidence for this decay mode. The measured
branching fractions are B(B+ -> Dbar*0 tau+ nu_tau)=(2.12^{+0.28}_{-0.27}
(stat) +- 0.29 (syst)) % and B(B+ -> Dbar0 tau+ nu_tau)=(0.77 +- 0.22 (stat) +-
0.12 (syst)) %.Comment: 6 pages, 4 figures, submitted to Phys. Rev. Let
Observation of the DsJ(2317) and DsJ(2457) in B decays
We report the first observation of the B --> Dbar DsJ(2317) and B --> Dbar
DsJ(2457) decays based on 123.8 10^6 BBar events collected with the Belle
detector at KEKB. We observe the DsJ(2317) decay to Ds pi0 and DsJ(2457) decay
to the Ds* pi0 and Ds gamma final states. We also set 90% CL upper limits for
the decays DsJ(2317) --> Ds* gamma, DsJ(2457) --> Ds* gamma, DsJ(2457) --> Ds
pi0 and DsJ(2457) --> Ds pi+ pi-.Comment: 6 pages, 3 figures. A few minor corrections. Replaced by version
accepted to publication in Phys. Rev. Let
Observation of a near-threshold omega-J/psi mass enhancement in exclusive B-->K omega J/psi decays
We report the observation of a near-threshold enhancement in the omega-J/psi
invariant mass distribution for exclusive B-->K omega J/psi decays. The results
are obtained from a 253 fb-1 data sample that contains 275 million BB-bar meson
pairs that were collected near the Upsilon(4S) resonance with the Belle
detector at the KEKB asymmetric energy e+e- collider. The statistical
significance of the omega-J/psi mass enhancement is estimated to be greater
than 8 sigma.Comment: 12 pages, 4 figures, submitted to Physical Review Letter
- …