Dynamical symmetries and the Ermakov invariant

Ermakov systems possessing Noether point symmetry are identified among the Ermakov systems that derive from a Lagrangian formalism and, the Ermakov invariant is shown to result from an associated symmetry of dynamical character. The Ermakov invariant and the associated Noether invariant, are sufficient to reduce these systems to quadratures

On the Lie symmetries of a class of generalized Ermakov systems

The symmetry analysis of Ermakov systems is extended to the generalized case where the frequency depends on the dynamical variables besides time. In this extended framework, a whole class of nonlinearly coupled oscillators are viewed as Hamiltonian Ermakov system and exactly solved in closed form

Analytical performance and clinical utility of the INNOTEST (R) PHOSPHO-TAU(181P) assay for discrimination between Alzheimer's disease and dementia with Lewy bodies

Background: Total tau (T-tau) and beta-amyloid((1-42)) (A beta(1-42)) levels in cerebrospinal fluid (CSF) can differentiate Alzheimer's disease (AD) from normal aging or depressive pseudo-dementia. Differential diagnosis from dementia with Lewy bodies (DLB) in clinical settings is difficult. Methods: The analytical performance of the INNOTEST (R) PHOSPHO-TAU((181P)) assay was validated in terms of selectivity, sensitivity, specificity, precision, robustness, and stability. Clinical utility of the assay alone, or combined with T-tau and AP1-421 for discrimination of AD (n=94) from patients suffering from DLB (n=60) or from age-matched control subjects (CS) (n=60) was assessed in a multicenter study. Results: CSF concentrations of tau phosphorylated at threonine 181 (P-tau(181P)) in AD was significantly higher than in DLB and CS. Discriminant analysis, a classification tree, and logistic regression showed that P-tau(181P) was the most statistically significant single variable of the three biomarkers for discrimination between AD and DLB. Conclusions: P-tau(181P) quantification is a robust and reliable assay that may be useful in discriminating AD from DLB

On the generalized Hamiltonian structure of 3D dynamical systems

The Poisson structures for 3D systems possessing one constant of motion can always be constructed from the solution of a linear PDE. When two constants of the motion are available the problem reduces to a quadrature and the structure functions include an arbitrary function of them

O marketing esportivo: diferenças e semelhanças entre futebol e voleibol

TCC (Graduação) - Universidade Federal de Santa Catarina. Centro de Desportos. Curso de Graduação em Educação Física.Os clubes brasileiros começaram a olhar o marketing esportivo com outros olhos no inicio do século XX, principalmente no futebol para competir com os altos salários pagos por clubes europeus. Já no voleibol o marketing foi utilizado para atrair investidores para a criação de equipes, pois até então o investimento no esporte era pequeno. Esse foi dois exemplos de como o marketing pode ajudar as equipes desportivas na arrecadação de capital para o investimento no esporte. O objetivo desse estudo foi analisar as semelhanças e diferenças entre o marketing esportivo entre equipes profissionais de futebol e voleibol, sendo utilizada como metodologia uma pesquisa básica de abordagem qualitativa. Foram realizadas entrevistas semi-estruturadas com a amostra na qual se pode constatar que os dois esportes apresentam em seus departamentos de marketing diferenças e similaridades que ocorrem para suas equipes se adaptarem ao mercado e adquirirem novos patrocinadores

Comment on "A note on the construction of the Ermakov-Lewis invariant"

We show that the basic results on the paper referred in the title [J. Phys. A: Math. Gen. v. 35 (2002) 5333-5345], concerning the derivation of the Ermakov invariant from Noether symmetry methods, are not new