604 research outputs found
Mineralogia de alguns solos da Bacia Sedimentar do Recôncavo Baiano
Ten soil profiles representative of the region known as "Reconcavo Baiano" (Sedimentary Basin) in Bahia State, were studied with the main objective of collecting information on the mineralogy of their respective clay fraction to determine their weathering sequence. Two of the profiles were taken form a Red-Yellow Podzolic soil and eight from Grumosols (Vertisol). Clay fraction were obtained from each horizon of the ten profiles through routine fractionation of the soil sample. These were pre-treated to eliminate soluble salts, organic mather and free iron oxides. The samples were then analysed qualitatively and quantitatively to determine their mineralogical composition. The results indicated that kaolinite was the dominant clay mineral in the Red-Yellow Podzolic with an average of 55%. Among the 2.1 minerals, mica was the main mineral with 15%. The transformation mica to kaolinite was observed. The 2:1 minerals (mica, vermieulite and montmorillonite) were dominant minerals in Grumosols (70 to 80%) and that montmorillonite was the main mineral. The transformation montmorillonite to kaolinite was observed. There was differencces in the weathering in these soils. According to kaolinite amount these profiles were grouped as following: Profiles BS5 and BS8 as soils with low kaolinite amount (average of 5%); profiles BS9 and BS10 as relatively high amount of kaolinite (average of 30%) and the others profiles as intermediate kaolinite amount.Foram estudados dez perfis de solos representativos da Bacia Sedimentar do Recôncavo Baiano com o principal objetivo de examinar a mineralogia da fração argila e suas implicações genéticas. Para tanto foram coletados dois perfis de Podzólico Vermelho Amarelo e oito de Grumossois. Amostras de argila de cada horizonte foram obtidas através de fracionamento de rotina. Tais amostras sofreram pré-tratamento para a eliminação de sais solúveis, matéria orgânica e óxidos de ferro livres. Em seguida foram analisadas qualitativa e quantitativamente. A caulinita foi o mineral dominante no Podzólico Vermelho Amarelo com teores médios de 55%. Entre os minerais de grade 2:1 a mica foi dominante com teores médios de 15%. Ficou evidente a transformação mica-caulinita. Nos Grumossois a porcentagem dos minerais de grade 2:1 (mica vermiculita e montmorilonita) está em torno de 70 a 80%. Dentre estes a montmorilonita é o mineral dominante. Ficou evidente a transformação montmorilonita caulinita para tais perfis. Mesmo entre os perfis de Grumossois houve diferença de intemperismo. Tais solos foram grupados em: perfis BS5 e BS8 sendo perismo. Tais solos com baixo teor de caulinita (teor médio 5%); perfis BS9 e BS10 com teor relativamente elevado de caulinita (teor médio 30%) e os demais perfis com teores intermediários de caulinita
New drugs from traditional medicines: pharmacological evaluation of plant extracts from Chapada Diamantina (Brazil)
Plants are rich sources of medicines and Brazil is among the most biodiverse nations in the world.info:eu-repo/semantics/publishedVersio
BF models, Duality and Bosonization on higher genus surfaces
The generating functional of two dimensional field theories coupled to
fermionic fields and conserved currents is computed in the general case when
the base manifold is a genus g compact Riemann surface. The lagrangian density
is written in terms of a globally defined 1-form and a
multi-valued scalar field . Consistency conditions on the periods of
have to be imposed. It is shown that there exist a non-trivial dependence of
the generating functional on the topological restrictions imposed to . In
particular if the periods of the field are constrained to take values , with any integer, then the partition function is independent of the
chosen spin structure and may be written as a sum over all the spin structures
associated to the fermions even when one started with a fixed spin structure.
These results are then applied to the functional bosonization of fermionic
fields on higher genus surfaces. A bosonized form of the partition function
which takes care of the chosen spin structure is obtainedComment: 17 page
Dynamical Breakdown of Symmetry in a (2+1) Dimensional Model Containing the Chern-Simons Field
We study the vacuum stability of a model of massless scalar and fermionic
fields minimally coupled to a Chern-Simons field. The classical Lagrangian only
involves dimensionless parameters, and the model can be thought as a (2+1)
dimensional analog of the Coleman-Weinberg model. By calculating the effective
potential, we show that dynamical symmetry breakdown occurs in the two-loop
approximation. The vacuum becomes asymmetric and mass generation, for the boson
and fermion fields takes place. Renormalization group arguments are used to
clarify some aspects of the solution.Comment: Minor modifications in the text and figure
Modeling the circular economy in environmentally extended input-output tables: Methods, software and case study
A circular economy is an industrial system that is restorative or regenerative by intention or design. During the last decade, the circular economy became an attractive paradigm to increase global welfare while minimizing the environmental impacts of economic activities. Although several studies concerning the potential benefits and drawbacks of policies that implement the new paradigm have been performed, there is currently no standardized theoretical model or software to execute such assessment. In order to fill this gap, in the present paper we show how to perform these analyses using Environmentally Extended Input-Output Analysis. We also describe a python package (pycirk) for modeling Circular Economy scenarios in the context of the Environmentally Extended Multi-Regional Input-Output database EXIOBASE V3.3, for the year 2011. We exemplify the methods and software through a what-if zero-cost case study on two circular economy strategies (Resource Efficiency and Product Lifetime Extension), four environmental pressures and two socio-economic factors.Industrial Ecolog
Static quantities of the W boson in the SU_L(3) X U_X(1) model with right-handed neutrinos
The static electromagnetic properties of the boson, and
, are calculated in the SU_L(3)} \times U_X(1) model with
right-handed neutrinos. The new contributions from this model arise from the
gauge and scalar sectors. In the gauge sector there is a new contribution from
a complex neutral gauge boson and a singly-charged gauge boson .
The mass of these gauge bosons, called bileptons, is expected to be in the
range of a few hundreds of GeV according to the current bounds from
experimental data. If the bilepton masses are of the order of 200 GeV, the size
of their contribution is similar to that obtained in other weakly coupled
theories. However the contributions to both and are
negligible for very heavy or degenerate bileptons. As for the scalar sector, an
scenario is examined in which the contribution to the form factors is
identical to that of a two-Higgs-doublet model. It is found that this sector
would not give large corrections to and .Comment: New material included. Final version to apppear in Physical Review
Local non-Gaussianity from rapidly varying sound speeds
We study the effect of non-trivial sound speeds on local-type non-Gaussianity
during multiple-field inflation. To this end, we consider a model of
multiple-field DBI and use the deltaN formalism to track the super-horizon
evolution of perturbations. By adopting a sum separable Hubble parameter we
derive analytic expressions for the relevant quantities in the two-field case,
valid beyond slow variation. We find that non-trivial sound speeds can, in
principle, curve the trajectory in such a way that significant local-type
non-Gaussianity is produced. Deviations from slow variation, such as rapidly
varying sound speeds, enhance this effect. To illustrate our results we
consider two-field inflation in the tip regions of two warped throats and find
large local-type non-Gaussianity produced towards the end of the inflationary
process.Comment: 30 pages, 7 figures; typos corrected, references added, accepted for
publication in JCA
Accidental Inflation in the Landscape
We study some aspects of fine tuning in inflationary scenarios within string
theory flux compactifications and, in particular, in models of accidental
inflation. We investigate the possibility that the apparent fine-tuning of the
low energy parameters of the theory needed to have inflation can be generically
obtained by scanning the values of the fluxes over the landscape. Furthermore,
we find that the existence of a landscape of eternal inflation in this model
provides us with a natural theory of initial conditions for the inflationary
period in our vacuum. We demonstrate how these two effects work in a small
corner of the landscape associated with the complex structure of the Calabi-Yau
manifold P^4_[1,1,1,6,9] by numerically investigating the flux vacua of a
reduced moduli space. This allows us to obtain the distribution of observable
parameters for inflation in this mini-landscape directly from the fluxes.Comment: 40 pages, 11 figure
Haematological and biochemical parameters in Churra-da-Terra-Quente ewes from the northeast of Portugal
Hematological and biochemical parameters, including plasma electrolytes and thyroid hormones, were determined in 73 clinically healthy Churra-da-Terra-Quente ewes, a typical breed from the northeast of Portugal. The hemogram values were: erythrocytes 9.8±1.51012/L; haemoglobin 118.1±19.1g/L; haematocrit 40.8±5.9%; leukocytes 5.7±1.8109/L; and platelets 544.3±177.2109/L. The thrombin time was 17.3±1.7 seconds. The values of biochemical parameters were: total protein 76.4±6.1g/L; glucose 2.87±0.60mmol/L; total cholesterol 1.65±0.33mmol/L; aspartate aminotransferase 155.9±49.2U/L; alanine aminotransferase 23.2±9.6U/L; γ-glutamyl transferase 48.0±18.7U/L; total alkaline phosphatase 121.6±76.1U/L; glutamate dehydrogenase 6.4±3.7U/L; urea 7.32±2.22mmol/L; creatinine 123.0±54.1μmol/L; total calcium 2.53±0.25mmol/L; phosphorus 2.10±0.46mmol/L; magnesium 1.01±0.09mmol/L; sodium 152.04±3.65mmol/L; potassium 4.7±0.4mmol/L; ionized calcium 1.32±0.07mmol/L; total thyroxine 111.75±42.29nmol/L; total triiodothyronine 1.01±0.28nmol/L; free T4 11.93±1.78pmol/L; free T3 4.22±1.33pmol/L; and thyroid-stimulating hormone 0.18±0.19μIU/mL. Although differences among the Churra-da-Terra-Quente breed and other breeds may occur, the hematological and biochemical parameters, plasma electrolytes, and thyroid hormones, for this indigenous breed, were generally situated within the reference intervals previously reported for sheep
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