The Fokker-Planck equation for a bistable potential

The Fokker-Planck equation is studied through its relation to a Schrodinger-type equation. The advantage of this combination is that we can construct the probability distribution of the Fokker-Planck equation by using well-known solutions of the Schrodinger equation. By making use of such a combination, we present the solution of the Fokker-Planck equation for a bistable potential related to a double oscillator. Thus, we can observe the temporal evolution of the system describing its dynamic properties such as the time tau to overcome the barrier. By calculating the rates k = 1/tau as a function of the inverse scaled temperature 1/D, where D is the diffusion coefficient, we compare the aspect of the curve k x 1/D, with the ones obtained from other studies related to four different kinds of activated process. We notice that there are similarities in some ranges of the scaled temperatures, where the different processes follow the Arrhenius behavior. We propose that the type of bistable potential used in this study may be used, qualitatively, as a simple model, whose rates share common features with the rates of some single rate-limited thermally activated processes. (C) 2014 Elsevier B.V. All rights reserved.

Shell beds from the Low Head Member (Polonez Cove Formation, early Oligocene) at King George Island, west Antarctica: new insights on facies analysis, taphonomy and environmental significance

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Longitudinal evaluation of fluoride levels in nails of 18-30-month-old children that were using toothpastes with 500 and 1100 mu g F/g

ObjectivesThis study aimed to evaluate the fluoride concentration in the fingernails and toenails of children aged 18-30months during use of fluoride-containing toothpastes supplemented with calcium glycerophosphate (CaGP) or sodium trimetaphosphate (TMP).MethodsAccording to the toothpaste used, children (n=56) were randomly assigned into three groups: 500gF/g with 1% TMP, 500gF/g with 0.25% CaGP, and 1100gF/g. Fingernails and toenails were collected monthly over a period of 330days, from the beginning of toothpaste use. Fluoride concentration in the water consumed by the volunteers and fluoride intake from diet and toothpaste were also determined. Fluoride analyses were performed with the electrode after hexamethyldisiloxane-facilitated diffusion or by the direct method, according to the samples. Data passed normality and homoscedasticity tests and were analyzed by 2-way analysis of variance (anova) and 1-way anova followed by Student-Newman-Keuls test (P<0.05).ResultsFluoride levels in the fingernails and toenails as well as fluoride intake from toothpaste were similar for the groups treated with 500gF/g with 1% TMP and 500gF/g with 0.25% CaGP toothpastes, but significantly lower than the 1100 gF/g group (P<0.05). No significant differences were noted among the groups regarding fluoride intake from diet and that by water consumed by the volunteers (P>0.05).ConclusionThe results of the longitudinal study suggest that the level of fluoride present in nails was lower with the use of toothpastes with a low fluoride concentration.

Increased atmospheric carbon dioxide concentration: effects on eucalypt rust (Puccinia psidii), C:N ratio and essential oils in eucalypt clonal plantlets

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Isolation and characterization of microsatellites markers for two South American frogs (Leptodactylus bufonius and L. chaquensis) using next generation sequencing

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Turpilóquio em português e italiano: reflexões sobre marcas de uso de itens tabus em dicionários

In this paper, we tried to understand the place of taboo words and their importance in the language. We focused questions about the taboo and how words can be prohibited. We elected swear words as our object of research because these words have an important place in the lexicon of many speakers, and they are present in books and movies, as well as in the everyday speech. Therefore, we tried to show that they must be analyzed with attention and also free from prejudices. We found out that the use of bad words can be very different in the languages selected and they reflect thus the culture of the languages involved.

Alterações cardiovasculares em pacientes com malária por Plasmodium vivax

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Utilizações de informações genômicas para o melhoramento genético de características de crescimento em bovinos da raça Nelore

Pós-graduação em Genética e Melhoramento Animal - FCAV

Relação entre materiais dentários e o complexo dentino-pulpar

Despite the strong valorization of the esthetics and its relationship with restorative materials, the biological principles of any clinical procedure are extremely important to maintain the vitality of the dentin-pulp complex. Dentin and pulp tissue are susceptible to different kinds of irritants such as toxins from microorganisms, traumatic procedures of cavity preparation, as well as toxic components released by restorative materials applied in non recommended clinical situations. Initially, the pulp responds to irritation by starting an inflammatory reaction which involves outward movement of dentinal fluid and intratubular deposition of immunoglobulins, upregulation of odontoblast activities, presence of immune cells and their cytokines as well as local expression of neuropeptides and chemokines. After these initial events, the inflammation process can be resolved associated or not to sclerotic dentin formation and reactionary dentin deposition. If high intensity offensive stimuli are applied to the dentin-pulp complex, death of odontoblasts takes place and consequently pulp ageing or even partial necrosis of this tissue may occurs. Thereby, clinicians need to be aware about the physiological and pathological features of the dentin-pulp complex as well as the possible biological consequences of different clinical procedures. In this way, the dentists should be able to carry out minimally aggressive operative techniques and to select the more appropriate restorative materials for each specific clinical situation in order to obtain excellent clinical results associated to the maintenance of pulp vitality.

Prevalence of the hepatitis C virus among university employees in São Paulo, southeastern Brazil: predictive factors and geoprocessing spatial analysis

Background There are limited studies on the prevalence and risk factors associated with hepatitis C virus (HCV) infection. Objective Identify the prevalence and risk factors for HCV infection in university employees of the state of São Paulo, Brazil. Methods Digital serological tests for anti-HCV have been performed in 3153 volunteers. For the application of digital testing was necessary to withdraw a drop of blood through a needlestick. The positive cases were performed for genotyping and RNA. Chi-square and Fisher’s exact test were used, with P-value <0.05 indicating statistical significance. Univariate and multivariate logistic regression were also used. Results Prevalence of anti-HCV was 0.7%. The risk factors associated with HCV infection were: age >40 years, blood transfusion, injectable drugs, inhalable drugs (InDU), injectable Gluconergam®, glass syringes, tattoos, hemodialysis and sexual promiscuity. Age (P=0.01, OR 5.6, CI 1.4 to 22.8), InDU (P<0.0001, OR=96.8, CI 24.1 to 388.2), Gluconergam® (P=0.0009, OR=44.4, CI 4.7 to 412.7) and hemodialysis (P=0.0004, OR=90.1, CI 7.5 – 407.1) were independent predictors. Spatial analysis of the prevalence with socioeconomic indices, Gross Domestic Product and Human Development Index by the geoprocessing technique showed no positive correlation. Conclusions The prevalence of HCV infection was 0.7%. The independent risk factors for HCV infection were age, InDU, Gluconergan® and hemodialysis. There was no spatial correlation of HCV prevalence with local economic factors.

Quantified power Doppler as a predictor of delayed graft function after renal transplantation

No safe ultrasound (US) parameters have been established to differentiate the causes of graft dysfunction.To define US parameters and identify the predictors of normal graft evolution, delayed graft function (DGF), and rejection at the early period after kidney transplantation.Between June 2012 and August 2013, 79 renal transplant recipients underwent US examination 1-3 days posttransplantation. Resistive index (RI), power Doppler (PD), and RI + PD (quantified PD) were assessed. Patients were allocated into three groups: normal graft evolution, DGF, and rejection.Resistive index of upper and middle segments and PD were higher in the DGF group than in the normal group. ROC curve analysis revealed that RI + PD was the index that best correlated with DGF (cutoff = 0.84). In the high RI + PD group, time to renal function recovery (6.33 +/- A 6.5 days) and number of dialysis sessions (2.81 +/- A 2.8) were greater than in the low RI + PD group (2.11 +/- A 5.3 days and 0.69 +/- A 1.5 sessions, respectively), p = 0.0001. Multivariate analysis showed that high donor final creatinine with a relative risk (RR) of 19.7 (2.01-184.7, p = 0.009) and older donor age (RR = 1.17 (1.04-1.32), p = 0.007) correlated with risk DGF.Quantified PD (RI + PD) was the best DGF predictor. PD quantification has not been previously reported .