Boundary crisis and suppression of Fermi acceleration in a dissipative two-dimensional non-integrable time-dependent billiard

Some dynamical properties for a dissipative time-dependent oval-shaped billiard are studied. The system is described in terms of a four-dimensional nonlinear mapping. Dissipation is introduced via inelastic collisions of the particle with the boundary, thus implying that the particle has a fractional loss of energy upon collision. The dissipation causes profound modifications in the dynamics of the particle as well as in the phase space of the non-dissipative system. In particular, inelastic collisions can be assumed as an efficient mechanism to suppress Fermi acceleration of the particle. The dissipation also creates attractors in the system, including chaotic. We show that a slightly modification of the intensity of the damping coefficient yields a drastic and sudden destruction of the chaotic attractor, thus leading the system to experience a boundary crisis. We have characterized such a boundary crisis via a collision of the chaotic attractor with its own basin of attraction and confirmed that inelastic collisions do indeed suppress Fermi acceleration in two-dimensional time-dependent billiards. (C) 2010 Elsevier B.V. All rights reserved.

Fate of non O157 Shiga toxigenic Escherichia coli in composted cattle manure

Determinou-se o tempo necessário para a eliminação de Escherichia coli Shigatoxigênica (STEC) não-O157 em esterco bovino composto, obtido de fezes frescas de três vacas portadoras de cepas STEC não-O157 que apresentavam o gene stx 2. Foram utilizados dois sistemas de compostagem, o primeiro foi um buraco de 0,6m escavado no solo e o segundo um monte apresentando uma arquitetura piramidal com um metro de altura. Todos os dias, durante os primeiros 10 dias e a cada cinco dias durante um mês, uma amostra de três pontos diferentes dos dois sistemas de compostagem foram coletadas e semeadas para determinar a presença de E. coli e a presença do gene stx 2 nas células, sendo que em cada coleta a temperatura do sistema de compostagem foi determinada. Células de STEC não-O157 sobreviveram por 8, 25 e 30 dias nas temperaturas de 42, 40 e 38ºC, respectivamente, no sistema enterrado no solo, enquanto que no sistema de monte as células foram detectadas por 4, 4 e 7 dias em temperaturas de 65, 58 e 52ºC, respectivamente. A temperatura e os microrganismos presentes na microbiota do sistema de compostagem parecem ser os responsáveis pela eliminação do patógeno. Pode-se concluir que os dois sistemas de compostagem utilizados mostraram-se eficientes na eliminação de células de STEC. A aplicação de esterco após compostagem deve diminuir o risco de contaminação ambiental e a disseminação do patógeno.

Progesterone (PR), Oestrogen (ER-alpha and ER-beta) and Oxytocin (OTR) Gene Expression in the Oviduct and Uterus of Pregnant and Non-pregnant Bitches

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

Expression of beta-human chorionic gonadotropin (beta-hCG) in non-trophoblastic elements of transitional cell carcinoma of the bladder: possible relationship with the prognosis.

Transitional cell carcinoma (TCC) of the bladder is a neoplasm with variability in its clinical behavior. Although there are several studies correlating stage and ABO isoantigen expression with invasiveness, there is no single predictor factor to assess the potential invasiveness, especially in the low grade, non-invasive TCC. In the present study we evaluated the correlation of histological grade plus stage and the expression of beta human chorionic gonadotropin (beta-hCG), in 100 cases of TCC, with the clinical behavior. These features were correlated with tumor progression in patients with at least two years of follow up. We observed more aggressiveness in G4 group (high grade and invasive) (93% had tumor progression) when compared to G1 group (low grade and superficial) (11% had tumor progression). However in 25.5% of the TCC cases (groups G2: low grade and invasive and G3: high grade and superficial) the clinical behavior was intermediate, showing some limitation in using grading and staging only, as a predictive factor. There was an expression of beta-hCG in 21.4% of the cases in up to 25% of the tumor cells without any trophoblastic morphology. These beta-hCG producing TCC had a strong correlation with aggressiveness: 39.1% and 12.8% of the TCC expressed beta-hCG with and without tumor progression, respectively.

Non-aqueous Titration of Gatifloxacin in Pharmaceutical Formulations using Perchloric Acid

An inexpensive, simple, precise and rapid method for the determination of fluoroquinolone gatifloxacin in tablets is described. The procedure is based on the use of volumetric dosage in a non-aqueous medium in glacial acetic acid with 0.1 M perchloric acid. The method validation yielded good results and included the precision, recovery and accuracy. It was also found that the excipients in the commercial tablet preparation did not interfere with the assay.

Instantaneously measured traits may detect non-plastic ecophysiological performances in response to drought, explaining distributions of Styrax species in the Cerrado

We analyzed the differences between irrigated and non-irrigated plants of three congeneric Styrax species that present distinct distribution patterns in the physiognomies of the Cerrado vegetation in Brazil. Styrax ferrugineus showed a stomatal conductance (gs) unresponsive to soil water deficit in potted plants. This may explain the high gas exchange and photochemical efficiency found in this species, which is well adapted to the Cerrado sensu stricto (s. str.), a savanna-type vegetation. S. camporum, which is widely distributed in the Cerrado sensu lato (s. l.) areas, was the only species that exhibited increased intrinsic water use efficiency on the days of maximum water deficit. This result distinguishes S. camporum from S. pohlii, which is a forest species, since the gs of both species decreased during the days of maximum water stress. In contrast to other studies, we propose that instantaneously measured traits, such as leaf gas exchange rates and chlorophyll fluorescence, may be used to detect non-plastic performances in response to environmental stress, helping explain distinct geographical distributions of congeneric species in the Cerrado vegetation. © 2013 Springer-Verlag Berlin Heidelberg.

Context-dependence in seed removal by lekking and non-lekking frugivorous birds in Brazilian Atlantic forest

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Imputation of non-genotyped individuals using genotyped progeny in Nellore, a Bos indicus cattle breed

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Non-synonymous mutations mapped to chromosome X associated with andrological and growth traits in beef cattle

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

Phospho-mTOR in non-tumour and tumour bladder urothelium: Pattern of expression and impact on urothelial bladder cancer patients

Urothelial bladder carcinoma (UBC) is heterogeneous in its pathology and clinical behaviour. Evaluation of prognostic and predictive biomarkers is necessary, in order to produce personalised treatment options. The present study used immunohistochemistry to evaluate UBC sections containing tumour and non-tumour areas from 76 patients, for the detection of p-mTOR, CD31 and D2-40 (blood and lymphatic vessels identification, respectively). Of the non-tumour and tumour sections, 36 and 20% were scored positive for p-mTOR expression, respectively. Immunoexpression was observed in umbrella cells from non-tumour urothelium, in all cell layers from non-muscle-invasive (NMI) tumours (including expression in superficial cells), and in spots of cells from muscle-invasive (MI) tumours. Positive expression decreased from non-tumour to tumour urothelium, and from pTl/pTis to pT3/pT4 tumours; however, the few pT3/pT4 positive cases had worse survival rates, with 5-year disease-free survival being significantly lower. Angiogenesis occurrence was impaired in pT3/pT4 tumours that did not express p-mTOR. In conclusion, p-mTOR expression in non-tumour umbrella cells is likely a reflection of their metabolic plasticity, and extension to the inner layers of the urothelium in NMI tumours is consistent with an enhanced malignant potential. The expression in cell spots in a few MI tumours and absence of expression in the remaining tumours is intriguing and requires further research. Additional studies regarding the up- and downstream effectors of the mTOR pathway should be conducted.

Acute and subchronic antihyperglycemic activities of bowdichia virgilioides roots in non diabetic and diabetic rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Residence Time Distribution Models Derived from Non-Ideal Laminar Velocity Profiles in Tubes

The theoretical E-curve for the laminar flow of non-Newtonian fluids in circular tubes may not be accurate for real tubular systems with diffusion, mechanical vibration, wall roughness, pipe fittings, curves, coils, or corrugated walls. Deviations from the idealized laminar flow reactor (LFR) cannot be well represented using the axial dispersion or the tanks-in-series models of residence time distribution (RTD). In this work, four RTD models derived from non-ideal velocity profiles in segregated tube flow are proposed. They were used to represent the RTD of three tubular systems working with Newtonian and pseudoplastic fluids. Other RTD models were considered for comparison. The proposed models provided good adjustments, and it was possible to determine the active volumes. It is expected that these models can be useful for the analysis of LFR or for the evaluation of continuous thermal processing of viscous foods.

Chaos-based communication systems in non-ideal channels

Recently, many chaos-based communication systems have been proposed. They can present the many interesting properties of spread spectrum modulations. Besides, they can represent a low-cost increase in security. However, their major drawback is to have a Bit Error Rate (BER) general performance worse than their conventional counterparts. In this paper, we review some innovative techniques that can be used to make chaos-based communication systems attain lower levels of BER in non-ideal environments. In particular, we succinctly describe techniques to counter the effects of finite bandwidth, additive noise and delay in the communication channel. Although much research is necessary for chaos-based communication competing with conventional techniques, the presented results are auspicious. (C) 2011 Elsevier B. V. All rights reserved.

Modeling of continuous thermal processing of a non-Newtonian liquid food under diffusive laminar flow in a tubular system

The classic conservative approach for thermal process design can lead to over-processing, especially for laminar flow, when a significant distribution of temperature and of residence time occurs. In order to optimize quality retention, a more comprehensive model is required. A model comprising differential equations for mass and heat transfer is proposed for the simulation of the continuous thermal processing of a non-Newtonian food in a tubular system. The model takes into account the contribution from heating and cooling sections, the heat exchange with the ambient air and effective diffusion associated with non-ideal laminar flow. The study case of soursop juice processing was used to test the model. Various simulations were performed to evaluate the effect of the model assumptions. An expressive difference in the predicted lethality was observed between the classic approach and the proposed model. The main advantage of the model is its flexibility to represent different aspects with a small computational time, making it suitable for process evaluation and design. (C) 2012 Elsevier Ltd. All rights reserved.

Oral leukoplakia manifests differently in smokers and non-smokers

Oral leukoplakias (OL) are potentially malignant lesions that are typically white in color. Smoking is considered a risk factor for developing OL, and dysplastic lesions are more prone to malignant transformation. The aim of this study was to describe the clinical features observed in dysplastic and non-dysplastic OL in both smokers and nonsmokers. A total of 315 cases of OL were retrieved and separated into either dysplastic or non-dysplastic lesions, and these cases were further categorized as originating in either smokers or non-smokers. Frequencies of the type of OL lesion, with respect to whether the patients smoked, were established. The results demonstrated that 131 cases of OL were dysplastic (74 smokers and 57 non-smokers), and 184 were non-dysplastic (96 smokers and 88 non-smokers). For OL cases in smokers for which information about alcohol consumption was also available (84 cases), the results revealed no significant difference in the amount of dysplastic and non-dysplastic lesions. Dysplastic lesions were more frequent in male smokers and in non-smoking females. The median age of smokers with cases of OL was significantly lower than in non-smokers; the lowest median ages were observed for female smokers with dysplastic OL. The most frequent anatomical sites of dysplastic lesions were the floor of the mouth in smokers and the tongue in non-smokers. Dysplastic lesions in smokers were significantly smaller than non-dysplastic lesions in non-smokers. Being a male smoker, being female, being younger, and having smaller lesions were associated with dysplastic features in OL. These clinical data may be important for predicting OL malignant transformation.