Isotropic Ornstein-Uhlenbeck flows

Isotropic Brownian flows (IBFs) are a fairly natural class of stochastic flows which has been studied extensively by various authors. Their rich structure allows for explicit calculations in several situations and makes them a natural object to start with if one wants to study more general stochastic flows. Often the intuition gained by understanding the problem in the context of IBFs transfers to more general situations. However, the obvious link between stochastic flows, random dynamical systems and ergodic theory cannot be exploited in its full strength as the IBF does not have an invariant probability measure but rather an infinite one. Isotropic Ornstein-Uhlenbeck flows are in a sense localized IBFs and do have an invariant probability measure. The imposed linear drift destroys the translation invariance of the IBF, but many other important structure properties like the Markov property of the distance process remain valid and allow for explicit calculations in certain situations. The fact that isotropic Ornstein-Uhlenbeck flows have invariant probability measures allows one to apply techniques from random dynamical systems theory. We demonstrate this by applying the results of Ledrappier and Young to calculate the Hausdorff dimension of the statistical equilibrium of an isotropic Ornstein-Uhlenbeck flow

Estudos das interações dos íons Fe(III) com ácido cafeico na presença de ácido húmico

TCC (graduação) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Curso de Química.A biodisponibilidade e o transporte de íons metálicos no solo para as plantas são fortemente influenciados pela presença de ligantes orgânicos no ambiente. O ácido cafeico ocorre na rizosfera de muitas plantas, juntamente com outros compostos polifenólicos. Desta forma, plantas com deficiência de Ferro exsudam ácido cafeico para tornar o Ferro biodisponível, suprindo a necessidade desse importante íon metálico. Neste trabalho foram investigadas as interações dos íons Fe(III) com o ácido cafeico para poder avaliar, na presença de ácidos húmicos, onde esse íon está complexado, e se será liberado. As interações foram determinadas pela técnica de titulação potenciométrica, que é muito eficaz na determinação das constantes de equilíbrio. Por isso é a técnica escolhida para caracterizar os equilíbrios ácido-báse e de complexação. Além do estudo potenciométrico, foram realizados espectroscopias UV-Vis para comparar com os resultados potenciométricos e estudos eletroquímicos por voltametria cíclica, envolvendo o ácido cafeico em presença e ausência do íon metálico. Esses estudos são importantes para entender o mecanismo de absorção de cátions metálicos por raízes de plantas dicotiledôneas. Esses estudos mostram que em meio ácido, neutro, e levemente alcalino, o ácido húmico libera íons Fe(III) para o ácido cafeico, facilitando a absorção do íon Fe(III) pelas raízes das plantas

Relationship between Bilirubin and Auditory Function in Premature Neonates

Research has shown hyperbilirubinemia is more prevalent in preterm infants than in term infants. Hyperbilirubin is toxic to the central nervous system and may cause neurological impairments in newborns with the most consistent impairment being auditory dysfunction. However, national guidelines are needed which address bilirubin levels in premature infants. The study objective was to determine the relationship between bilirubin levels and auditory function in preterm infants. The auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) were prospectively investigated in premature infants while monitoring total serum bilirubin (TSB) levels. Ten subjects with mean gestational age of 31.5 weeks and mean peak-TSB of 7.91 mg/dL were enrolled. The posthoc peak-TSB to birth weight ratio placed all subjects in the control group. Spearman's correlation coefficient indicated no significant correlation between peak-TSB levels and auditory function. Further research with hyperbilirubinemia subjects is needed to determine when preterm infants' auditory function is affected

The Frequency of Redistricting in Nebraska and the Balance Between One Person, One Vote and Electoral Stability: How Often Is Too Often?

I. Introduction . . . . . 576 II. Case Progression . . . . . 579 A. Factual Background . . . . . 579 B. District Court Decision . . . . . 583 C. Nebraska Supreme Court Decision . . . . . 586 III. Analysis . . . . . 587 A. Overview of Nebraska Case Law . . . . . 587 1. Preliminary Look at Section 32-553 in State ex rel. Steinke v. Lautenbaugh . . . . . 587 2. Meaning of “Most Recent Census Data” Answered in Pelzer v. Bellevue . . . . . 588 B. The Question of Frequency . . . . . 590 C. One-Person, One-Vote Standard: Reynolds v. Sims . . . . . 592 D. Federal Courts and the Frequency Question ....... 593 E. Nebraska Constitutional Guidance . . . . . 595 F. Other Statutory Guides: Redistricting Due to Annexation . . . . . 599 G. Potential Results: Ohio’s Experience . . . . . 601 IV. Implications . . . . . 602 V . Conclusion . . . . . 60