408 research outputs found
On the Practical use of Variable Elimination in Constraint Optimization Problems: 'Still-life' as a Case Study
Variable elimination is a general technique for constraint processing. It is
often discarded because of its high space complexity. However, it can be
extremely useful when combined with other techniques. In this paper we study
the applicability of variable elimination to the challenging problem of finding
still-lifes. We illustrate several alternatives: variable elimination as a
stand-alone algorithm, interleaved with search, and as a source of good quality
lower bounds. We show that these techniques are the best known option both
theoretically and empirically. In our experiments we have been able to solve
the n=20 instance, which is far beyond reach with alternative approaches
Relation between emotional intelligence and the physical-sportive activity in the extracurricular schedule
La finalidad del presente trabajo es analizar las relaciones existentes entre la práctica y no practica de actividades físicas y deportes en horario extraescolar con la inteligencia emocional en estudiantes de Educación Secundaria Obligatoria. Así mismo, también vamos a analizar si en función del tipo de deporte practicado (individual, adversario y colectivo) existen diferencias entre ellos. En el estudio participaron un total de 126 estudiantes del primer y segundo ciclo de la ESO. El instrumento utilizado fue el cuestionario BarOn EQ-i: YV (S) (2002), y la realización de una pregunta para conocer si practicaban actividad física o deporte y, en caso afirmativo, que indicaran que deporte practicaban. Las técnicas de análisis de datos incluyen una prueba t para muestras independientes y un análisis univariado de covarianza o ANOVA. Los resultados obtenidos indicaron que la práctica de actividades deportivas está asociada a mayores niveles de inteligencia emocional.The purpose of the present paper is to analyse the current connections between the practice and not practice of physical activities or sports in extracurricular schedule with the emotional intelligence in students of Secondary Obligatory Education. Likewise, we also propose to analyse if the type of sports (individual sport, adversary sport, team sport) has influence between them. The participants in our study were 126 students of the first and second cycle of Secondary Obligatory Education. The tools that we have used were the test BarOn EQ-i: YV (S) (2002) and one question to know if the students practice sports or not and if the answer was positive, write what sport they practice. The analysis of information’s techniques include a student’s t-test for independents samples and an analysis of variance or ANOVA. The obtained results indicate that practice physical activities or sports is associated with high levels of emotional intelligence
A Direct Arylation-Cyclisation Reaction for the Construction of Medium-Sized Rings
A strategy for assembling biaryls linked through a medium‐sized ring is herein presented. π‐Complexation of fluoroarenes to chromium tricarbonyl activates the molecule towards both C−H activation and nucleophilic aromatic substitution without covalently altering the molecular connectivity of the arene. The construction of bridged biaryl molecules with 6–10‐membered core rings is achieved through a one‐pot C−H arylation/nucleophilic aromatic substitution sequence. The methodology is applicable to the synthesis of heterocyclic as well as fully carbocyclic rings
Influence of ocular biometric factors on the defocus curve in an enlarged depth-of-focus intraocular lens
Background: To assess the influence of biometric measurements on the defocus curve after the implantation of enlarged depth-of-focus (EDoF) intraocular lens (IOL). Methods: Patients who underwent cataract surgery with bilateral implantation of Tecnis Symfony IOL were enrolled. Preoperatively, axial length (AL), corneal keratometry (K), pupil size and corneal aberrations were measured. 1 month after surgery, distance, intermediate, and near visual acuities (VA) were recorded. At 3 months, monocular and binocular corrected contrast sensitivities under photopic and mesopic lighting conditions were measured with CSV-1000E test. At 6-months, the defocus curve between −5.00 to + 3.00 diopters (D) was assessed in steps of 0.50 D, and NEI-RQL-42 questionnaire was administered. Results: One hundred thirty one eyes of 66 patients were included. Binocular logMAR VA better than 0.1 for intermediate vision was obtained in 90% of patients, whereas only 17.7% obtained that result in near vision. The rate of satisfaction was high (96%) and most of them (85.5%) had no or little difficulties in near vision. The mean amplitude of the defocus curve was 2.35D ± 0.73D, and smaller AL, smaller pupils, younger age, and male sex were associated with wider range of clear vision. Conclusions: Tecnis Symfony IOL enables functional vision at all distances, but demographic variables and preoperative biometric measurements like AL and pupil size influence the postoperative amplitude of the defocus curve. These parameters could be used to predict the performance of EDoF IOLs
Diagnostic and prognostic value of antibodies against chimeric fibrin/filaggrin citrullinated synthetic peptides in rheumatoid arthritis
Introduction: Evidence suggests that citrullinated fibrin(ogen) may be a potential in vivo target of anticitrullinated protein/peptide antibodies (ACPA) in rheumatoid arthritis (RA). We compared the diagnostic yield of three enzyme-linked immunosorbent assay (ELISA) tests by using chimeric fibrin/filaggrin citrullinated synthetic peptides (CFFCP1, CFFCP2, CFFCP3) with a commercial CCP2-based test in RA and analyzed their prognostic values in early RA. Methods: Samples from 307 blood donors and patients with RA (322), psoriatic arthritis (133), systemic lupus erythematosus (119), and hepatitis C infection (84) were assayed by using CFFCP- and CCP2-based tests. Autoantibodies also were analyzed at baseline and during a 2-year follow-up in 98 early RA patients to determine their prognostic value. Results: With cutoffs giving 98% specificity for RA versus blood donors, the sensitivity was 72.1% for CFFCP1, 78.0% for CFFCP2, 71.4% for CFFCP3, and 73.9% for CCP2, with positive predictive values greater than 97% in all cases. CFFCP sensitivity in RA increased to 80.4% without losing specificity when positivity was considered as any positive anti-CFFCP status. Specificity of the three CFFCP tests versus other rheumatic populations was high (> 90%) and similar to those for the CCP2. In early RA, CFFCP1 best identified patients with a poor radiographic outcome. Radiographic progression was faster in the small subgroup of CCP2-negative and CFFCP1-positive patients than in those negative for both autoantibodies. CFFCP antibodies decreased after 1 year, but without any correlation with changes in disease activity. Conclusions: CFFCP-based assays are highly sensitive and specific for RA. Early RA patients with anti-CFFCP1 antibodies, including CCP2-negative patients, show greater radiographic progression
On Tackling the Limits of Resolution in SAT Solving
The practical success of Boolean Satisfiability (SAT) solvers stems from the
CDCL (Conflict-Driven Clause Learning) approach to SAT solving. However, from a
propositional proof complexity perspective, CDCL is no more powerful than the
resolution proof system, for which many hard examples exist. This paper
proposes a new problem transformation, which enables reducing the decision
problem for formulas in conjunctive normal form (CNF) to the problem of solving
maximum satisfiability over Horn formulas. Given the new transformation, the
paper proves a polynomial bound on the number of MaxSAT resolution steps for
pigeonhole formulas. This result is in clear contrast with earlier results on
the length of proofs of MaxSAT resolution for pigeonhole formulas. The paper
also establishes the same polynomial bound in the case of modern core-guided
MaxSAT solvers. Experimental results, obtained on CNF formulas known to be hard
for CDCL SAT solvers, show that these can be efficiently solved with modern
MaxSAT solvers
Los servicios tecnológicos en el proceso de enseñanza de grado y como herramienta eficaz de la interacción Universidad/Empresa
Fil: Brigante, N. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Tecnología Química Industria; Argentina.Fil: Frigerio, S. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Tecnología Química Industria; Argentina.Fil: Nadal, F. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Tecnología Química Industria; Argentina.Fil: López, A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Ciencia y Tecnología de los Alimentos; Argentina.Fil: López, A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Microbiología General y de los Alimentos; Argentina.Fil: Yorio, D. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Química Analítica General; Argentina.Fil: Severini, H. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Química Analítica General; Argentina.Fil: Larrosa, N. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Ciencia y Tecnología de los Alimentos; Argentina.Fil: Larrosa, N. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Problemática y Gestión Ambiental; Argentina.Fil: Oroná, C. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Química Analítica General; Argentina.Fil: Oroná, C. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Problemática y Gestión Ambiental; Argentina.El proceso y las estrategias de enseñanza universitaria han evolucionado significativamente en las últimas décadas. La incorporación de las TICS, las aulas virtuales y el aprendizaje
basado en problemas son algunos ejemplos de ello. Con respecto a este último, se trata de brindar al estudiante experiencias prácticas en situaciones reales y códigos relativos a las
organizaciones laborales. Además, varios autores han informado que la mejor manera de aprender es la convergencia de la atención en la actividad y la visión de la profesión
mediante la práctica. Por otra parte, las empresas requieren, frecuentemente, servicios tecnológicos de alto nivel, con una componente multidisciplinaria que algunas veces no
puede ser satisfecha por los profesionales que integran su staff.http://www.efn.unc.edu.ar/departamentos/quimicaindustrial/CIEXIQ/Libro%20completo%20preliminar.pdfFil: Brigante, N. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Tecnología Química Industria; Argentina.Fil: Frigerio, S. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Tecnología Química Industria; Argentina.Fil: Nadal, F. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Tecnología Química Industria; Argentina.Fil: López, A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Ciencia y Tecnología de los Alimentos; Argentina.Fil: López, A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Microbiología General y de los Alimentos; Argentina.Fil: Yorio, D. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Química Analítica General; Argentina.Fil: Severini, H. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Química Analítica General; Argentina.Fil: Larrosa, N. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Ciencia y Tecnología de los Alimentos; Argentina.Fil: Larrosa, N. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Problemática y Gestión Ambiental; Argentina.Fil: Oroná, C. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Química Analítica General; Argentina.Fil: Oroná, C. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Problemática y Gestión Ambiental; Argentina.Otras Ingeniería Químic
Experimental Evaluation of Subgraph Isomorphism Solvers
International audienceSubgraph Isomorphism (SI) is an NP-complete problem which is at the heart of many structural pattern recognition tasks as it involves finding a copy of a pattern graph into a target graph. In the pattern recognition community, the most well-known SI solvers are VF2, VF3, and RI. SI is also widely studied in the constraint programming community, and many constraint-based SI solvers have been proposed since Ullman, such as LAD and Glasgow, for example. All these SI solvers can solve very quickly some large SI instances, that involve graphs with thousands of nodes. However, McCreesh et al. have recently shown how to randomly generate SI instances the hardness of which can be controlled and predicted, and they have built small instances which are computationally challenging for all solvers. They have also shown that some small instances, which are predicted to be easy and are easily solved by constraint-based solvers, appear to be challenging for VF2 and VF3. In this paper, we widen this study by considering a large test suite coming from eight benchmarks. We show that, as expected for an NP-complete problem, the solving time of an instance does not depend on its size, and that some small instances coming from real applications are not solved by any of the considered solvers. We also show that, if RI and VF3 can solve very quickly a large number of easy instances, for which Glasgow or LAD need more time, they fail at solving some other instances that are quickly solved by Glasgow or LAD, and they are clearly outperformed by Glasgow on hard instances. Finally, we show that we can easily combine solvers to take benefit of their complementarity
De la quinta a la mesa: experiencias en escuelas primarias de La Plata
Este trabajo recoge la experiencia de un proyecto de extensión de la Universidad Nacional de La Plata (UNLP) que comenzó en el año 2012. Sus integrantes son profesionales y estudiantes de distintas carreras de grado y unidades académicas. La propuesta constituye una iniciativa para el abordaje interdisciplinario del consumo responsable de frutas y hortalizas en niños de nivel primario.Facultad de Ciencias Agrarias y Forestale
An investigation of the dynamics of intramammary infections acquired during the dry period on European dairy farms
The dry period is acknowledged as playing a key role in mastitis epidemiology and yet surprisingly few studies have explored dry period infection dynamics in detail. The aim of this study was to investigate the dynamics of intramammary infection across a cohort of dairy herds in Europe. Five hundred and twenty-two cows were recruited from 12 farms in 6 European countries. All cows received antibiotic dry cow therapy but teat sealants were not used. All quarters of all cows were sampled for bacteriology at drying off and in the week immediately postcalving. Two ipsilateral quarters were also sampled for bacteriology in each cow 2 and 6 wk after drying off. Cows were body condition scored and teats assessed for cleanliness at all sampling time points and for the presence of a keratin plug during the dry period. Other cow-level parameters such as historic somatic cell counts and milk yields before drying off were collated from farm records. Univariable and multivariable analyses were undertaken to investigate the etiology, prevalence, and dynamics of infection during the dry period and associated influential factors. In summary, environmental mastitis pathogens predominated. Although gram-positive major pathogens were typically well controlled and did not increase in prevalence across the dry period, gram-negative pathogens generally increased in prevalence. There was an increase in the number of quarters that yielded no growth across the dry period, although this was driven by minor rather than major mastitis pathogen control. Other than the presence of a gram-positive or gram-negative pathogen 6 wk after drying off, the measured parameters were not influential when considering their effect on the presence of pathogens postcalving. Analysis also suggested that the early and mid dry period may be more important with respect to the timing of acquisition of infection than previously thought. We observed substantial variation in the etiology and prevalence of different pathogens on different farms with, in all cases, at least one of the 12 herds experiencing the opposite of the others with respect to increases and decreases in pathogen prevalence. Overall, this study confirms the importance of the dry period in mastitis epidemiology but highlights the importance of assessing and understanding infection dynamics on individual units. The lack of influence of the cow and quarter factors measured in this study suggests that herd and management factors may be more influential
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