Comparação de ferramentas de tópicos em textos sob o paradigma de aprendizado estatístico não supervisionado.

Neste trabalho pretende-se estudar e explorar ferramentas de aprendizado de tópicos hierárquicos, através de coleções textuais e teoria estatísticaCIIC 2014. Nº 14602

Scattering and Trapping of Nonlinear Schroedinger Solitons in External Potentials

Soliton motion in some external potentials is studied using the nonlinear Schr\"odinger equation. Solitons are scattered by a potential wall. Solitons propagate almost freely or are trapped in a periodic potential. The critical kinetic energy for reflection and trapping is evaluated approximately with a variational method.Comment: 9 pages, 7 figure

Estudo comparativo entre os metadados da Agência de Informação Embrapa e do Acervo Documental do AINFO.

A embrapa Informática Agropecuária é a principal responsável pela concretização de duas importantes iniciativas no âmbito da organização da informação: o AINFO e a Agência de Informação Embrapa.bitstream/CNPTIA/10650/1/comtec66.pdfAcesso em: 28 maio 2008

Critical wave-packet dynamics in the power-law bond disordered Anderson Model

We investigate the wave-packet dynamics of the power-law bond disordered one-dimensional Anderson model with hopping amplitudes decreasing as $H_{nm}\propto |n-m|^{-\alpha}$. We consider the critical case ($\alpha=1$). Using an exact diagonalization scheme on finite chains, we compute the participation moments of all stationary energy eigenstates as well as the spreading of an initially localized wave-packet. The eigenstates multifractality is characterized by the set of fractal dimensions of the participation moments. The wave-packet shows a diffusive-like spread developing a power-law tail and achieves a stationary non-uniform profile after reflecting at the chain boundaries. As a consequence, the time-dependent participation moments exhibit two distinct scaling regimes. We formulate a finite-size scaling hypothesis for the participation moments relating their scaling exponents to the ones governing the return probability and wave-function power-law decays

DNA barcoding of moon jellyfish (Cnidaria, Scyphozoa, Ulmaridae, Aurelia): two cryptic species from the Azores (ne atlantic, macaronesia), and evaluation of the non-íIndigenous species (NIS)

Moon jellies are some of the most popular, widely distributed, and best-studied marine jellyfish. By the end of the past century only two or three Aurelia species were recognized, but with the rise of DNA barcoding studies, around thirty Aurelia species are presently accepted. Most of the species are morphologically indistinguishable and have restricted biogeography. We reveal, with COI, 16S, and ITS1-5.8S sequence data, two (pseudo-)cryptic species of Aurelia, potentially endemic to the Azores ecoregion, herein provisionally classified as A. "cf. pseudosolida" and A. "misteriosa". These species are closely related to the Mediterranean lineages of A. pseudosolida and A. persea, respectively. In the Azores, the shape of the campanula and oral arms readily distinguishes the two species: the former with folded oral arms and globose campanula, and the latter with flattened campanula and thick and long oral arms. Previous reports of A. solida and A. aurita in the Azores should generally correspond to A. "misteriosa" and A. cf. pseudosolida, respectively. The phylogenetic (re-)examination of the available DNA barcodes of Aurelia only evidenced human-mediated dispersal for A. coerulea, A. relicta, and A. aurita. Aurelia solida cannot be yet considered NIS in the Mediterranean. More jellyfish DNA (meta)barcoding should reveal further cryptic diversity, biological invasions, and phylogeographic inferences.Programa Operacional Açores 2020”, within the project “Águas-VivAz”–ref.: ACORES-01-0145- FEDER-000119info:eu-repo/semantics/publishedVersio

EFFECT OF OSMOTIC DEHYDRATION IN THE APPLE (Pyrus malus) VARIETIES GALA, GOLD AND FUJI

Some raw material characteristics were evaluated in three apple varieties Gala, Gold and Fuji. The study was undertaken to collect information in order to identify the effects of initial tissue properties on mass transport phenomena in general, and osmotic processing responses in particular. The apples, obtained from the local market, were washed, peeled and cut into 10 mm cube. After this, the samples were dehydrated in sugar osmotic solution (50% w/w) at 30°C and 110 rpm of agitation. The ratio of foodstuff to osmotic solution was greater than 1:20. The mass transfer kinetics was measured in intervals of 20 minutes during 3 hours. The mass transfer kinetics of the different apple varieties has presented different behavior during the osmotic dehydration. The apples vs. Gala have presented the highest water loss and solid gain. The vs. Gold presented a lower tendency to solid uptake

Development of bioplastics from agro-wastes

During centuries synthetic polymers have been used in a variety of applications in the everyday of human life. They became essential due to its versatility, durability and low cost [1]. However, due to their excessive use, several drawbacks as its resistance to the decomposition, toxicity after incineration and accumulation in the environment induce negative ecological impact in landfills and water contamination [2]. Moreover, plastics production implies the use of non-renewable resources, such as, oil and natural gas that represents about 8 % of global consumption [1,2]. Therefore, become crucial to search for new ecological materials toward innovative and cost-effective fabrication of environmentally degradable plastics demonstrating similar performance to conventional ones [1,3]. Simultaneously, the high amount of agro-wastes generated from food industry have been a growing concern, around 1.3 billion tons are leftover, which became an environmental and financial issue [1]. Among these agro-waste stands out, food waste, halum and stems of vegetables/fruits, grains and seeds, from which it is possible to obtain natural polymers [3]. Biopolymers exhibit unique properties and can be produced from plants and crops wastes. Rubber, proteins, starch and cellulose are some of the examples [4]. Cellulose has been used for the production of biopolymers, nevertheless, because of the difficulty inherent in its extraction process, various methods have been studied in order to optimize this process. Currently, cellulose derivatives are used, which is an example of cellulose acetate, whose chemical purification process is quite costly and lengthy [1]. Thus, the present work, aims to directly synthetize biopolymers from agro-wastes. Green chemistry methodology is applied to extract natural polymers, such as cellulose, from vegetable wastes. Structural, morphological and mechanical characterization of the produced materials are accessed and compared with conventional synthetic polymers. Also, biodegradability assays will be performed to check the microorganisms’ capability to assimilate the produced bioplastics

Field sexual attraction in the sorghum midge, Contarinia sorghicola (Coquillett, 1899) (Diptera, Cecidomyiidae).

No campo, fêmeas da mosca do sorgo, Contarinia sorghicola (Coquillett, 1899), atraem machos da especie para o acasalamento atraves da emissao de feromonio, o que foi comprovado atraves da utilizacao de armadilhas adesivas contendo femeas virgens ou extratos destas, a nivel de campo. O periodo de maior atratividade ocorreu entre 7:30 e 8:30 horas.Suplemento