Dynamical estimates of chaotic systems from Poincar\'e recurrences

We show that the probability distribution function that best fits the distribution of return times between two consecutive visits of a chaotic trajectory to finite size regions in phase space deviates from the exponential statistics by a small power-law term, a term that represents the deterministic manifestation of the dynamics, which can be easily experimentally detected and theoretically estimated. We also provide simpler and faster ways to calculate the positive Lyapunov exponents and the short-term correlation function by either realizing observations of higher probable returns or by calculating the eigenvalues of only one very especial unstable periodic orbit of low-period. Finally, we discuss how our approaches can be used to treat data coming from complex systems.Comment: subm. for publication. Accepted fpr publication in Chao

Ephippia of Cladocera (Crustacea: Branchiopoda) from the Oligocene Tremembé palaeolake, Brazil

© 2015 Taylor & Francis. Ephippia of Cladocera (Crustacea: Branchiopoda) are found in the Oligocene deposits of Tremembé Formation (Taubaté Basin, Southeast Brazil). Thirty specimens from a short stratigraphic interval of a 115-m section of a core drilled in Taubaté city, São Paulo state, have been studied. Based on the morphology, we assumed that they might belong to two diferent species of Daphnia (Ctenodaphnia) which lived either in the Tremembé palaeolake or in some surrounding temporary waters. Our find represents the oldest record of fossil ephippia in South America and the second record of Daphnia (Ctenodaphnia) in the former Gondwana. A tentative palaeolimnological interpretation is proposed based on the ephippia occurrences, allied to ostracod and lithological data

Experimental dynamic evaluation of three-phase reactors

The hydrodynamic parameters were determined for two different three-phase systems (fluidized-bed and trickle-bed) through the experimental evaluation of the dynamic residence time distribution in the gas or liquid phase. For different fluid phase flow rates the fluidized-bed system was operated with a tracer in the gas phase and in the trickle-bed with a tracer in the liquid phase. The analysis of the processes was achieved through the application of different models representing the dynamic behavior of tracers present in the gas and liquid phases with a simulation of experimental operations of the three-phase reactors. The transfer functions developed for the two systems made it possible to estimate the hydrodynamic parameters providing the gas holdup (2.22 x 10-2 to 8.42 x 10-2) and the gas phase Peclet number (54.18 to 41.20) for the fluidized-bed and the liquid holdup (0.16 to 0.25), the liquid phase Peclet number (20.37 to 4.52) and wetting efficiency (0.34 to 0.56) for the trickle-bed.443452Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

A minimal cytomegalovirus intron A variant can improve transgene expression in different mammalian cell lines.

Made available in DSpace on 2018-07-01T01:26:14Z (GMT). No. of bitstreams: 1 Quilici2013ArticleAMinimalCytomegalovirusIntronA.pdf: 267916 bytes, checksum: a0678d07681cb4ac9d04a72f07b2d182 (MD5) Previous issue date: 2013-08-12bitstream/item/179295/1/Quilici2013-Article-AMinimalCytomegalovirusIntronA.pd

DRIS standards for nutritional evaluation of Phaseolus vulgaris in Cerrado, Goiás State, Brazil.

The knowledge of nutritional requirements of beans, the efficiency of soil acidity correction and the fertilization programs are essential to increase productivity. The Integrated Recommendation and Diagnosis System (DRIS) assists with nutritional diagnosis of cultivated plants based on existing interactions between nutrients and the hierarchizing of limitations. This study aimed at establishing standards using the DRIS method for areas of production of irrigated common beans and at determining the most limiting nutritional factors to production using leaf analyses interpreted by concentration ranges and DRIS. Eighteen different beanproducing areas were selected in a central pivot irrigation system, from which 82 sampling points were established to collect leaves of crop and determine their nutritional contents. The reference population had productivity of over 3,000 kg ha- 1. Using DRIS, we determined that phosphorus is the most limiting nutrient regarding its deficiency, with great sensitivity to diagnose nutritional problems of plants, especially micronutrients. Phosphorus (68.3%), molybdenum (65.9%), iron (64.6 %) and sodium (63.4%) and are nutrients with highest percentage of samples presenting levels below adequate according to sufficiency ranges for plants. Using DRIS, we can evaluate interactions among nutrients and determine of the magnitude of crop nutritional limitation whether due to deficiency or excess. These results may indicate which nutrients are limiting the crop productive capacity, allowing greater efficiency in its correction in soil

Modelling \u3ci\u3eLeucaena\u3c/i\u3e Biomass Under Rainfed Production Systems of Semiarid Regions

The climatic variability of semiarid regions is the main source of uncertainties associated with forage and animal production, indicating a need for tools that accurately estimate forage production in order to construct a forage budgeting plan for livestock. This study simulated the biomass of Leucaena (Leucaena leucocephala) using the PHYGROW model in four locations located in Brazilian Semiarid. The work was carried out based on field data collected from 2019 to 2021. After sowing in 2018, leucaena was harvested when it reached 200 cm and to a target residual height of 70 cm. The biomass (fresh matter) was weighed, sampled and dried to obtain the total forage biomass (BFT) of each sample. The BFT was also estimated using the PHYGROW model, with field data being used to parameterize, calibrate and validate the model. The model performance, in turn, was evaluated based on the mean forecast error (BIAS %), root mean square error (RMSE) and Willmott index. Afterwards, a BFT time series was downloaded for each location, with the highest biomass simulated for each year being evaluated in the @Risk regarding their probability distribution. Thereafter, probability calculations of biomass production were performed, based on different levels of warranty in SigmaPlot software (11.0). The model underestimated the BFT collected in two locations and overestimated BFT in the others. The Weibull function was the best one to describe the data. Regarding biomass production under a 95% natural warranty, it was observed that leucaena showed low variation among locations (2240 ± 752 kg of DM ha-1 year-1 ). The PHYGROW model accurately predicted the leucaena BFT which, in turn, demonstrated significant adaptation potential to the various soil and climate conditions of Brazilian Semiarid. The use of probability analysis can contribute to forage planning, thus reducing the uncertainties related to climate variability, especially in rainfed production systems of dry areas

Contribuição para o conhecimento de duas espécies de cupim do Vale do Paraíba (Estado de São Paulo)

In this paper, some notes on the termites Cornitermes bequaerti Emerson, 1952 and Syntermes silvestrii Holmgren, 1911, that are found in Vale do Paraíba, State of São Paulo, Brazil, are presented.Duas espécies de cupim do Vale do Paraíba, Estado de São Paulo, são estudadas. A primeira, Cornitermes bequaerti Emerson, 1952, é pouco conhecida, embora sua área de dispersão abranja três estados; a segunda espécie, Syntermes silvestrii Holmgren, 1911, é menos conhecida ainda, ocorrendo aparentemente apenas em São Paulo. As duas espécies constroem ninhos que afloram à superfície do solo; os termiteiros de C. bequaerti são encontrados em pastagens e eucaliptais e os de S. silvestrii, em pastagens

Prospecção estratégica do Café com Ciência para disseminação de publicações técnico-cientificas em acesso aberto da Embrapa Amapá.

bitstream/item/222814/1/CPAF-AP-2018-Prospeccao-estrategica-do-Cafe-com-Ciencia.pd