An analytical solution for the critical number of particles for stable bose-einstein condensation under the influence of an anisotropic potential

We have considered a Bose gas in an anisotropic potential. Applying the the Gross-Pitaevskii Equation (GPE) for a confined dilute atomic gas, we have used the methods of optimized perturbation theory and self-similar root approximants, to obtain an analytical formula for the critical number of particles as a function of the anisotropy parameter for the potential. The spectrum of the GPE is also discussed.

The bubbles or the boiling pot?: an ecosystemic approach to culture, environment and quality of life

For the diagnosis and prognosis of the problems of quality of life, a multidisciplinary ecosystemic approach encompasses four dimensions of being-in-the-world, as donors and recipients: intimate, interactive, social and biophysical. Social, cultural and environmental vulnerabilities are understood and dealt with, in different circumstances of space and time, as the conjugated effect of all dimensions of being-in-the-world, as they induce the events (deficits and assets), cope with consequences (desired or undesired) and contribute for change. Instead of fragmented and reduced representations of reality, diagnosis and prognosis of cultural, educational, environmental and health problems considers the connections (assets) and ruptures (deficits) between the different dimensions, providing a planning model to develop and evaluate research, teaching programmes, public policies and field projects. The methodology is participatory, experiential and reflexive; heuristic-hermeneutic processes unveil cultural and epistemic paradigms that orient subject-object relationships; giving people the opportunity to reflect on their own realities, engage in new experiences and find new ways to live better in a better world. The proposal is a creative model for thought and practice, providing many opportunities for discussion, debate and development of holistic projects integrating different scientific domains (social sciences, psychology, education, philosophy, etc.)

Democracy on the edge: limits and possibilities for the implementation of an urban reform agenda in Brazil

In Brazil the 1990s constituted years of institutional achievements in the fields of housing and urban rights, given the incorporation of the principles of the social function of cities and property, the recognition of tenure rights for slum dwellers and the direct participation of citizens in the decision making process of urban policies, within the 1988 Constitution. These proposals have become the pillars of the Urban Reform agenda which has penetrated the federal government apparatus since the creation of the Ministry of Cities under Lula's administration. The article evaluates the limits and possibilities for the implementation of this agenda through the analysis of two policies proposed by the Ministry: the National Council of Cities and the campaign for Participatory Master Plans. The approach is based on the organization of the Brazilian State in terms of urban development, the relationship with the political system and the characteristics of Brazilian democracy.

The development of an immobilized enzyme reactor containing glyceraldehyde-3-phosphate dehydrogenase from Trypanosoma cruzi: the effect of species' specific differences on the immobilization

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) plays an important role in the life cycle of the Trypanosoma cruzi, and an immobilized enzyme reactor (IMER) has been developed for use in the on-line screening for GAPDH inhibitors. An IMER containing human GAPDH has been previously reported; however, these conditions produced a T. cruzi GAPDH-IMER with poor activity and stability. The factors affecting the stability of the human and T. cruzi GAPDHs in the immobilization process and the influence of pH and buffer type on the stability and activity of the IMERs have been investigated. The resulting T. cruzi GAPDH-IMER was coupled to an analytical octyl column, which was used to achieve chromatographic separation of NAD+ from NADH. The production of NADH stimulated by D-glyceraldehyde-3-phosphate was used to investigate the activity and kinetic parameters of the immobilized T. cruzi GAPDH. The Michaelis-Menten constant (K-m) values determined for D-glyceraldehyde-3-phosphate and NAD(+) were K-m = 0.5 +/- 0.05 mM and 0.648 +/- 0.08 mM, respectively, which were consistent with the values obtained using the non-immobilized enzyme.

Soil carbon stocks under no-tillage mulch-based cropping systems in the Brazilian Cerrado: An on-farm synchronic assessment

No-tillage mulch-based (NTM) cropping systems have been widely adopted by farmers in the Brazilian savanna region (Cerrado biome). We hypothesized that this new type of management should have a profound impact on soil organic carbon (SOC) at regional scale and consequently on climate change mitigation. The objective of this study was thus to quantify the SOC storage potential of NTM in the oxisols of the Cerrado using a synchronic approach that is based on a chronosequence of fields of different years under NTM. The study consisted of three phases: (1) a farm/cropping system survey to identify the main types of NTM systems to be chosen for the chronosequence; (2) a field survey to identify a homogeneous set of situations for the chronosequence and (3) the characterization of the chronosequence to assess the SOC storage potential. The main NTM system practiced by farmers is an annual succession of soybean (Glycine max)or maize (Zea mays) with another cereal crop. This cropping system covers 54% of the total cultivated area in the region. At the regional level, soil organic C concentrations from NTM fields were closely correlated with clay + silt content of the soil (r(2) = 0.64). No significant correlation was observed (r(2) = 0.07), however, between these two variables when we only considered the fields with a clay + silt content in the 500-700 g kg(-1) range. The final chronosequence of NTM fields was therefore based on a subsample of eight fields, within this textural range. The SOC stocks in the 0-30 cm topsoil layer of these selected fields varied between 4.2 and 6.7 kg C m(-2) and increased on average (r(2) = 0.97) with 0.19 kg C m(-2) year(-1). After 12 years of NTM management, SOC stocks were no longer significantly different from the stocks under natural Cerrado vegetation (p < 0.05), whereas a 23-year-old conventionally tilled and cropped field showed SOC stocks that were about 30% below this level. Confirming our hypotheses, this study clearly illustrated the high potential of NTM systems in increasing SOC storage under tropical conditions, and how a synchronic approach may be used to assess efficiently such modification on farmers` fields, identifying and excluding non desirable sources of heterogeneity (management, soils and climate). (C) 2010 Elsevier B.V. All rights reserved.

Effect of impeller type and stirring frequency on the behavior of an AnSBBR in the treatment of low-strength wastewater

The influence of impeller type and stirring frequency on the performance of a mechanically stirred anaerobic sequencing batch reactor containing immobilized biomass on an inert support (AnSBBR - Anaerobic Sequencing Batch Biofilm Reactor) was evaluated. The biomass was immobilized on polyurethane foam cubes placed in a stainless-steel basket inside a glass cylinder. Each 8-h batch run consisted of three stages: feed (10 min), reaction (460 min) and discharge (10 min) at 30 degrees C. Experiments were performed with four impeller types, i.e., helical, flat-blade, inclined-blade and curved-blade turbines, at stirring frequencies ranging from 100 to 1100 rpm. Synthetic wastewater was used in all experiments with an organic-matter concentration of 530 +/- 37 mg/L measured as chemical oxygen demand (COD). The reactor achieved an organic-matter removal efficiency of around 87% under all investigated conditions. Analysis of the four impeller types and the investigated stirring frequencies showed that mass transfer in the liquid phase was affected not only by the applied stirring frequency but also by the agitation mode imposed by each impeller type. The best reactor performance at all stirring frequencies was obtained when agitation was provided by the flat-blade turbine impeller. (C) 2010 Elsevier Ltd. All rights reserved.

TOXICITY EVALUATION AS A TOOL TO ASSES THE PERFORMANCE OF AN ANAEROBIC IMMOBILIZED BIOMASS REACTOR

Effluents from pulp mill are usually toxic and mutagenic. This characteristic is mainly a consequence of xenobiotic compounds that are formed during the process. Global parameters such as chemical oxidation demand, total organic carbon and others, do not permit identify whether the toxic potential was remedied by the treatments or not. The objective of this research was to evaluate the performance of an horizontal-flow anaerobic immobilized biomass reactor (HAIB) treating the bleaching effluent from a Kraft pulp mill using toxicological (Daphnia similis - Ceriodaphnia sdvestrii) mutagenicity and citotoxicological assays (Allium cepa L). The results showed high sensibility of the test-organisms and capability of the anaerobic reactor to remove compounds that are exerting toxic and mutagenic effects. The bioassays represented an attractive alternative to water quality analyzes and the performance evaluation of treatments.

Effect of specific feed volume on the performance of an anaerobic sequencing batch biofilm reactor (AnSBBR) with circulation treating different wastewaters under different organic loads

The objective of this research was to study the behavior of two anaerobic sequencing batch reactors, containing immobilized biomass (AnSBBR), as a function of the ratio of the volume of treated medium in each cycle to the total volume of reaction medium. The reactors, in which mixing was accomplished by recirculation of the liquid phase, were maintained at 30 +/- 1 degrees C and treated different wastewaters in 8-h cycles. The operational conditions imposed had the objective to investigate whether maintenance of a residual volume in the reactor would affect, at the end of each cycle, process efficiency and stability, as well as to verify the intensity of the effect for different types of wastewaters and organic loading rates. The first reactor, with work volume of 2.5 L, treated reconstituted cheese whey at an organic loading rate of 12 g COD.L(-1).d(-1) and presented similar effluent quality for the four conditions under which it was operated: renewal of 100, 70, 50 and 25 % of its work volume at each cycle. Despite the fact that reduction in the renewed volume did not significantly affect effluent quality, in quantitative terms, this reduction resulted in an increase in the amount of organic matter removed by the first reactor. The second reactor, with work volume of 1.8 L, treated synthetic wastewater at organic loading rates of 3 and 5 g COD.L(-1).d(-1) and operated under two conditions for each loading: renewal of 100 and 50 % of its work volume. At the organic loading rate of 3 g COD.L(-1).d(-1), the results showed that both effluent quality and amount of organic matter removed by the second reactor were independent of the treated volume per cycle. At the organic loading rate of 5 g COD.L(-1).d(-1), although the reduction in the renewed volume did not affect the amount of organic matter removed by the reactor, effluent quality improved during reactor operation with total discharge of its volume. In general, results showed process stability under all conditions, evidencing reactor flexibility and the potential to apply this technology in the treatment of different types of wastewater.

Effects of bed materials on the performance of an anaerobic sequencing batch biofilm reactor treating domestic sewage

The objective of this study was to determine the best performance of an anaerobic sequencing batch biofilm reactor (AnSBBR) based on the use of four different bed materials as support for biomass immobilization. The bed materials utilized were Polyurethane foam (PU), vegetal carbon (VC), synthetic pumice (SP), and recycled low-density polyethylene (PE). The AnSBBR. with I total volume Of 7.2 L, was operated in 8-h batch cycles over 10 months, and fed with domestic sewage with an average influent chemical oxygen demand (COD) of 358 +/- 110 mg/L. The average effluent COD values were 121 +/- 31, 208 +/- 54, 233 +/- 52, and 227 +/- 51 mg/L. for PU, VC, SP, and PE, respectively. A modified first-order kinetic model was adjusted to temporal profiles of COD during a batch cycle, and the apparent kinetic constants were 0.52 +/- 0.05, 0.37 +/- 0.05, 0.80 +/- 0.04, and 0.30 +/- 0.021h(-1) for PU, VC, SP, and PE, respectively. Specific substrate utilization rates of 1.08, 0.11, and 0.86 mg COD/mg VS day were obtained for PU, VC, and PE, respectively. Although SP yielded the highest kinetic coefficient, PU was considered the best support, since SP presented loss of chemical constituents during the reactor`s operational phase. In addition, findings oil the microbial community were associated with the reactor`s performance data. Although PE did not show a satisfactory performance, an interesting microbial diversity was found oil its surface. Based oil the morphology and denaturing gradient gel electrophoresis (DGGE) results, PE showed the best capacity for promoting the attachment of methanogenic organisms, and is therefore a material that merits further analysis. PU was considered the Most suitable material showing the best performance in terms of efficiency of solids and COD removal. (C) 2007 Elsevier Ltd. All rights reserved.

Floquet stability analysis of the flow around an oscillating cylinder

This investigative work is concerned with the flow around a circular cylinder submitted to forced transverse oscillations. The goal is to investigate how the transition to turbulence is initiated in the wake for cases with different Reynolds numbers (Re) and displacement amplitudes (A). For each Re the motion frequency is kept constant, close to the Strouhal number of the flow around a fixed cylinder at the same Re. Stability analysis of two-dimensional periodic flows around a forced-oscillating cylinder is carried out with respect to three-dimensional infinitesimal perturbations. The procedure consists of performing a Floquet type analysis of time-periodic base flows, computed using the spectral/hp element method. With the results of the Floquet calculations, considerations regarding the stability of the system are drawn, and the form of the instability at its onset is obtained. The critical Reynolds number is observed to change with the amplitude of oscillation. With respect to instabilities, unstable modes with the same symmetry as mode A of a fixed cylinder are observed; however, they present different wavelengths. Also, the instabilities observed for the oscillating cylinder are distinctively stronger in the braid shear layers. Other unstable modes similar to mode B are found. Quasi-periodic modes are observed in the 2S wake, and subharmonic mode occurrences are reported in P + S wakes. (C) 2009 Elsevier Ltd. All rights reserved.

On the basic reproduction number and the topological properties of the contact network: An epidemiological study in mainly locally connected cellular automata

We study the spreading of contagious diseases in a population of constant size using susceptible-infective-recovered (SIR) models described in terms of ordinary differential equations (ODEs) and probabilistic cellular automata (PCA). In the PCA model, each individual (represented by a cell in the lattice) is mainly locally connected to others. We investigate how the topological properties of the random network representing contacts among individuals influence the transient behavior and the permanent regime of the epidemiological system described by ODE and PCA. Our main conclusions are: (1) the basic reproduction number (commonly called R(0)) related to a disease propagation in a population cannot be uniquely determined from some features of transient behavior of the infective group; (2) R(0) cannot be associated to a unique combination of clustering coefficient and average shortest path length characterizing the contact network. We discuss how these results can embarrass the specification of control strategies for combating disease propagations. (C) 2009 Elsevier B.V. All rights reserved.

Democracy on the Edge: Limits and Possibilities in the Implementation of an Urban Reform Agenda in Brazil

The 1990s in Brazil were a time of institutional advances in the areas of housing and urban rights following the signing of the new constitution in 1988 that incorporated the principles of the social function of cities and property, recognition of the right to ownership of informal urban squatters and the direct participation of citizens in urban policy decision processes. These propositions are the pillars of the urban reform agenda which, since the creation of the Ministry of Cities by the Lula government, has come under the federal executive branch. This article evaluates the limitations and opportunities involved in implementing this agenda on the basis of two policies proposed by the ministry - the National Cities Council and the campaign for Participatory Master Plans - focusing the analysis on government organization in the area of urban development in its relationship with the political system and the characteristics of Brazilian democracy. Resume Au Bresil, les annees 1990 ont ete marquees par des progres institutionnels en matiere de logement et de droits urbains, dans le sillage de la Constitution de 1988 qui integre les principes d`une fonction sociale de la ville et de la propriete urbaine, ainsi que la reconnaissance du droit a la propriete pour les squatters urbains et la participation directe des citoyens aux processus d`elaboration des politiques urbaines. Ce sont egalement les piliers du programme de reforme urbaine qui releve de l`executif federal depuis la creation d`un ministere des Villes par le gouvernement Lula. Pour evaluer les limites et potentiels lies a la mise en place de ce programme, cet article s`appuie sur deux politiques publiques proposees par le ministere, le Conseil national des villes et la campagne en faveur des Plans directeurs participatifs, en analysant plus particulierement l`organisation gouvernementale en matiere d`urbanisme par rapport au systeme politique et aux caracteristiques de la democratie bresilienne.

Box-Behnken design for the optimization of an enantioselective method for the simultaneous analysis of propranolol and 4-hydroxypropranolol by CE

An experimental design optimization (Box-Behnken design, BBD) was used to develop a CE method for the simultaneous resolution of propranolol (Prop) and 4-hydroxypropranolol enantiomers and acetaminophen (internal standard). The method was optimized using an uncoated fused silica capillary, carboxymethyl-beta-cyclodextrin (CM-beta-CD) as chiral selector and triethylamine/phosphoric acid buffer in alkaline conditions. A BBD for four factors was selected to observe the effects of buffer electrolyte concentration, pH, CM-beta-CD concentration and voltage on separation responses. Each factor was studied at three levels: high, central and low, and three center points were added. The buffer electrolyte concentration ranged from 25 to 75 mM, the pH ranged from 8 to 9, the CM-beta-CD concentration ranged from 3.5 to 4.5%w/v, and the applied run voltage ranged from 14 to 20 W. The responses evaluated were resolution and migration time for the last peak. The obtained responses were processed by Minitab (R) to evaluate the significance of the effects and to find the optimum analysis conditions. The best results were obtained using 4%w/v CM-beta-CD in 25 mM triethylamine/H(3)PO(4) buffer at pH 9 as running electrolyte and 17 kV of voltage. Resolution values of 1.98 and 1.95 were obtained for Prop and 4-hydroxypropranolol enantiomers, respectively. The total analysis time was around of 15 min. The BBD showed to be an adequate design for the development of a CE method, resulting in a rapid and efficient optimization of the pH and concentration of the buffer, cyclodextrin concentration and applied voltage.

Francoist Primary education: the schoolbook as an instrument of child indoctrination

The Francoist rule, mainly in its first decades, exerted a strong control upon education, which was left in the hands of the Catholic nationalist. Innumerous children`s schoolbooks were published driven by strong patriotic and religious bias. The authors aimed to shape the children`s minds based on the premises that supported the regimen: authority, hierarchy, order, abeyance, fear and devotion to God and the leader Francisco Franco. This paper analyzes the content of the elementary education books and shows how they were important instruments of child indoctrination marked by intolerance. The content and the images of the books contributed to construct an excluding national identity based on a heightened Catholic patriotism, stimulated heroism, martyrdom, child sacrifice, and hatred for the enemies of the religion and of ""mother Spain"".

Subjective memory impairment in a rural population with low education in the Amazon rainforest: an exploratory study

Background: The high prevalence of subjective memory impairment (SMI) in the elderly living in developed countries may be partly dependent on greater demand placed on them by new technologies. As part of a comprehensive study on cognitive impairment in a population living in the Amazon rainforest, we evaluated the prevalence of SMI and investigated the features associated with it. Methods: We evaluated 163 subjects (82 females) with a mean age of 62.3 years (50-94 years), 110 of whom were illiterate, using the answer to a single question ""Do you have memory problems?"" to classify them into groups with or without SMI. The assessment involved application of the Mini-mental State Examination (MMSE), delayed recall from the Brief Cognitive Battery designed for the evaluation of low educated and illiterate individuals, the Patient Questionnaire (PQ) of the Primary Care Evaluation of Mental Disorders (PRIME-MD), and the Happiness Analogical Scale. Results: A very high prevalence of SMI (70%) was observed, exceeding rates reported by similar studies conducted in developed countries. SMI was more frequent in women, whereas age and education did not impact on prevalence. Subjects with SMI had significantly more somatic and psychiatric symptoms on the PQ, as well as lower means on the MMSE, but not on the delayed recall test. Multiple logistic regressions showed that the most important factor associated with the presence of SMI was a high score on the PQ (OR: 3.84, p = 0.011). Conclusion: Psychological and somatic symptoms may be the principal cause of SMI in this population.