Zonal flows and long-distance correlations during the formation of the edge shear layer in the TJ-II stellarator

A theoretical interpretation is given for the observed long-distance correlations in potential fluctuations in TJ-II. The value of the correlation increases above the critical point of the transition for the emergence of the plasma edge shear flow layer. Mean (i.e. surface averaged, zero-frequency) sheared flows cannot account for the experimental results. A model consisting of four envelope equations for the fluctuation level, the mean flow shear, the zonal flow amplitude shear, and the averaged pressure gradient is proposed. It is shown that the presence of zonal flows is essential to reproduce the main features of the experimental observations.Comment: 19 pages, 7 figure

The CWKB particle production and classical condensate in de Sitter spacetime

The complex time WKB approximation is an effective tool in studying particle production in curved spacetime. We use it in this work to understand the formation of classical condensate in expanding de Sitter spacetime. The CWKB leads to the emergence of thermal spectrum that depends crucially on horizons (as in de Sitter spacetime) or observer dependent horizons (as in Rindler spacetime). A connection is sought between the horizon and the formation of classical condensate. We concentrate on de Sitter spacetime and study the cosmological perturbation of $k=0$ mode with various values of $m/H_0$. We find that for a minimally coupled free scalar field for $m^2/H_0^2<2$, the one-mode occupation number grows more than unity soon after the physical wavelength of the mode crosses the Hubble radius and soon after diverges as $N(t)\sim O(1)[\lambda_{phys}(t)/{H_0^{-1}}]^{2\sqrt{\nu^2-1/4}}$, where $\nu\equiv (9/4 -m^2/{H_0^2})^{1/2}$. The results substantiates the previous works in this direction. We also find the correct oscillation and behaviour of $N(z)$ at small $z$ from a single expression using CWKB approximation for various values of $m/H_0$. We also discuss decoherence in relation to the formation of classical condensate. We also find that the squeezed state formalism and CWKB method give identical results.Comment: 19 pages, revtex, 5 figure

Squeezed States of the Generalized Minimum Uncertainty State for the Caldirola-Kanai Hamiltonian

We show that the ground state of the well-known pseudo-stationary states for the Caldirola-Kanai Hamiltonian is a generalized minimum uncertainty state, which has the minimum allowed uncertainty $\Delta q \Delta p = \hbar \sigma_0/2$, where $\sigma_0 (\geq 1)$ is a constant depending on the damping factor and natural frequency. The most general symmetric Gaussian states are obtained as the one-parameter squeezed states of the pseudo-stationary ground state. It is further shown that the coherent states of the pseudo-stationary ground state constitute another class of the generalized minimum uncertainty states.Comment: RevTex4, 9 pages, no fingure; to be published in Journal of Physics

OBTAINING TEMPERATURE FIELDS AS A FUNCTION OF EFFICIENCY IN TIG WELDING BY NUMERICAL MODELING

The temperature field serves as the basis for predicting levels of residual stress in a welded joint. The aspects related to the mathematical modeling of complex welding procedures were pondered with the FEM: variations in the physical and mechanical properties of the materials as a function of the temperature, the transience and the speed of the welding process, the material phase transformations, the different mechanisms of heat exchange with the environment (convection and radiation), all them associated with a high level of nonlinearity. The heat source used in this analytical model for heat supply was the double ellipsoid model proposed by Goldak (2005), in which a 60 mm x 50 mm and 3 mm rectangular ASTM AH36 steel plate was used for the TIG process simulations. It was made a comparison of temperature fields for three different values of process efficiency (60%, 70% and 80%). The results showed many differences in the temperature fields following changes in the levels of residual stresses which will be determined in further studies

Human umbilical cord blood plasma as an alternative to animal sera for mesenchymal stromal cells in vitro expansion – A multicomponent metabolomic analysis

Mesenchymal Stromal cells (MSCs) have a potential role in cell-based therapies. Foetal bovine serum (FBS) is used to supplement the basal cell culture medium but presents several disadvantages and risks. Other alternatives have been studied, including human umbilical cord blood plasma (hUCBP), aiming at the development of xeno-free culturing protocols. A comparative characterization of multicomponent metabolic composition of hUCBP and commercial FBS based on Nuclear Magnetic Resonance (NMR) spectroscopy and multivariate statistical analysis was performed. The analysis of 1H-NMR spectra revealed both similarities and differences between the two proposed supplements. Similar metabolites (amino acids, glucose, lipids and nucleotides) were found in the hUCBP and FBS NMR spectra. The results show that the major difference between the metabolic profiles of the two proposed supplements are due to the significantly higher levels of glucose and lower levels of lactate, glutamate, alanine and branched chain amino acids in hUCBP. Similar or slightly different levels of important proteinogenic amino acids, as well as of nucleotides, lipids were found in the hUCBP and FBS. In order to validate it’s suitability for cell culture, umbilical cord-MSCs (UC-MSCs) and dental pulp stem cells (DPSCs) were expanded using hUCBP. In both hMSCs, in vitro culture with hUCBP supplementation presented similar to improved metabolic performances when compared to FBS. The two cell types tested expressed different optimum hUCBP percentage content. For DPSCs, the optimum hUCBP content was 6% and for UC-MSCs, 4%. Cultured hMSCs displayed no changes in senescence indicators, as well as maintained characteristic surface marker’s expression. FBS substitution was associated with an increase in early apoptosis events, in a dose dependent manner, as well as to slight up- and down-regulation of targeted gene’s expression. Tri-lineage differentiation capacity was also influenced by the substitution of FBS by hUCBP.info:eu-repo/semantics/publishedVersio

Processo de sobremoldação de vedante numa tampa plástica

O objeto da presente patente é o processo de sobremoldação de uma tampa Plástica com vedante incorporado, na qual é injetado o material de maior dureza sobre o De menor dureza. Este processo de sobremoldação é aplicado somente em bi-injecção (utilização de dois materiais ou mais), em tampas plásticas rígidas para embalagens de Forma redonda ou outras. A solução adotada passou por proteger o vedante (3) do fluxo (9) do material da tampa (2) de modo a evitar que este cause deformações no vedante (3) Durante o processo de enchimento. A forma de orientação precisa do fluxo (9) do sobre o Material de menor dureza (3) evita a deformação deste ultimo recorrendo aos diferenciais De pressão conjugados com a velocidade. Desta forma é possível injetar sobre um Material de menor dureza (3), um material de maior dureza (2)

Chromosome identification in the Andean common bean accession G19833 (Phaseolus vulgaris L., Fabaceae)

Characterization of all chromosomes of the Andean G19833 bean genotype was carried out by fluorescent in situ hybridization. Eleven single-copy genomic sequences, one for each chromosome, two BACs containing subtelomeric and pericentromeric repeats and the 5S and 45S ribosomal DNA (rDNA) were used as probes. Comparison to the Mesoamerican accession BAT93 showed little divergence, except for additional 45S rDNA sites in four chromosome pairs. Altogether, the results indicated a relative karyotypic stability during the evolution of the Andean and Mesoamerican gene pools of P. vulgaris

Afibrinogenemia secundária a acidente ofídico crotálico (Crotalus durissus terrificus)

This paper reports two cases of afibrinogenemia with normal platelet count following Crotalus durissus terrificus, snake bite Both patients presented high output acute renal failure and case two also had increased blood levels of CPK and LDH compatible with the diagnosis of rhabdomyolysis. Case one was given an unknown amount of antivenom and was treated with epsilonaminocaproic acid and a fresh whole blood transfusion and showed recovery of the coagulation disturbance 40 hours following these measures. Case two was given an adequate amount of crotalide antivenom and the coagulation tests performed 12 hours later showed a normal partial thromboplastin time and fibrinogen 86 mg/100ml. Case one presented no haemorrhagic disturbances. Case two presented persistent bleeding following venopuncture and after removal of impetigo crust in the legs. Acute renal failure was treated conservatively and both patients were discharged from the hospital with recovery of the renal function.Relatam se os casos de dois pacientes que desenvolveram afibrinogenemia sem consumo de plaquetas após terem sido picados por Crotalus durissus terrificus. Ambos também tiveram insuficiência renal aguda de alto débito e no caso nº 2 foi feito o diagnóstico de rabdomiólise através da elevação expressiva dos níveis séricos de CPK e DHL. O caso nº 1 recebeu dose não especificada de antiveneno e foi tratado com ácido épsilon-aminocaproico e transfusão de sangue fresco total tendo apresentado normalização dos testes de coagulação 40 horas após estas medidas. O caso nº 2 recebeu dose adequada de antiveneno crotálico e 12 horas depois já evidenciava recuperação do distúrbio da coagulação. O caso nº 1 evoluiu sem apresentar hemorragias. O caso nº 2 apresentou sangramento persistente nos locais de venóclise e após remoção de crostas de impetigo nas pernas. Ambos receberam tratamento conservador para a insuficiência renal aguda e tiveram alta com recuperação da função renal