Traffic-Related Air Pollution and Perinatal Mortality: A Case-Control Study

BACKGROUND: Ambient levels of air pollution may affect the health of children, as indicated by studies of infant and perinatal mortality. Scientific evidence has also correlated low birth weight and preterm birth, which are important determinants of perinatal death, with air pollution. However, most of these studies used ambient concentrations measured at monitoring sites, which may not consider differential exposure to pollutants found at elevated concentrations near heavy-traffic roadways. OBJECTIVES: Our goal was to examine the association between traffic-related pollution and perinatal mortality. METHODS: We used the information collected for a case-control study conducted in 14 districts in the City of Sao Paulo, Brazil, regarding risk factors for perinatal deaths. We geocoded the residential addresses of cases (fetal and early neonatal deaths) and controls (children who survived the 28th day of life) and calculated a distance-weighted traffic density (DWTD) measure considering all roads contained in a buffer surrounding these homes. RESULTS: Logistic regression revealed a gradient of increasing risk of early neonatal death with higher exposure to traffic-related air pollution. Mothers exposed to the highest quartile of the DWTD compared with those less exposed exhibited approximately 50% increased risk (adjusted odds ratio = 1.47; 95% confidence interval, 0.67-3.19). Associations for fetal mortality were less consistent. CONCLUSIONS: These results suggest that motor vehicle exhaust exposures may be a risk factor for perinatal mortality.

CAN OLD GALAXIES AT HIGH REDSHIFTS AND BARYON ACOUSTIC OSCILLATIONS CONSTRAIN H(0)?

A new age-redshift test is proposed in order to constrain H(0) on the basis of the existence of old high-redshift galaxies (OHRGs). In the flat Lambda cold dark matter model, the value of H(0) is heavily dependent on the mass density parameter Omega(M) = 1- Omega(Lambda). Such a degeneracy can be broken through a joint analysis involving the OHRG and baryon acoustic oscillation signature. By assuming a galaxy incubation time, t(inc) = 0.8 +/- 0.4 Gyr, our joint analysis yields a value of H(0) = 71 +/- 4 km s(-1) Mpc(-1) (1 sigma) with the best-fit density parameter Omega(M) = 0.27 +/- 0.03. Such results are in good agreement with independent studies from the Hubble Space Telescope key project and recent estimates of the Wilkinson Microwave Anisotropy Probe, thereby suggesting that the combination of these two independent phenomena provides an interesting method to constrain the Hubble constant.

Nonquadratic gauge fixing and global gauge invariance in the effective action

The possibility of having a gauge fixing term in the effective Lagrangian that is not a quadratic expression has been explored in spin-two theories so as to have a propagator that is both traceless and transverse. We first show how this same approach can be used in spontaneously broken gauge theories as an alternate to the 't Hooft gauge fixing which avoids terms quadratic in the scalar fields. This ""nonquadratic"" gauge fixing in the effective action results in two complex fermionic and one real bosonic ghost field. A global gauge invariance involving a fermionic gauge parameter, analogous to the usual Becchi-Rouet-Stora-Tyutin invariance, is present in this effective action.

Duality linking standard and tachyon scalar field cosmologies

In this work we investigate the duality linking standard and tachyon scalar field homogeneous and isotropic cosmologies in N + 1 dimensions. We determine the transformation between standard and tachyon scalar fields and between their associated potentials, corresponding to the same background evolution. We show that, in general, the duality is broken at a perturbative level, when deviations from a homogeneous and isotropic background are taken into account. However, we find that for slow-rolling fields the duality is still preserved at a linear level. We illustrate our results with specific examples of cosmological relevance, where the correspondence between scalar and tachyon scalar field models can be calculated explicitly.

Dynamical generation of mass in the D = (2+1) Wess-Zumino model

In this work we study the dynamical generation of mass in the massless N = 1 Wess-Zumino model in a three-dimensional spacetime. Using the tadpole method to compute the effective potential, we observe that supersymmetry is dynamically broken together with the discrete symmetry A(x) -> A(x). We show that this model, different from nonsupersymmetric scalar models, exhibits a consistent perturbative dynamical generation of mass after two-loop corrections to the effective potential.

Effect of spatial inhomogeneity on the mapping between strongly interacting fermions and weakly interacting spins

A combined analytical and numerical study is performed of the mapping between strongly interacting fermions and weakly interacting spins, in the framework of the Hubbard, t-J, and Heisenberg models. While for spatially homogeneous models in the thermodynamic limit the mapping is thoroughly understood, we here focus on aspects that become relevant in spatially inhomogeneous situations, such as the effect of boundaries, impurities, superlattices, and interfaces. We consider parameter regimes that are relevant for traditional applications of these models, such as electrons in cuprates and manganites, and for more recent applications to atoms in optical lattices. The rate of the mapping as a function of the interaction strength is determined from the Bethe-Ansatz for infinite systems and from numerical diagonalization for finite systems. We show analytically that if translational symmetry is broken through the presence of impurities, the mapping persists and is, in a certain sense, as local as possible, provided the spin-spin interaction between two sites of the Heisenberg model is calculated from the harmonic mean of the onsite Coulomb interaction on adjacent sites of the Hubbard model. Numerical calculations corroborate these findings also in interfaces and superlattices, where analytical calculations are more complicated.

A microscopic view of substitution reactions solvated by ionic liquids

The solvation effect of the ionic liquid 1-N-butyl-3-methylimidazolium hexafluorophosphate on nucleophilic substitution reactions of halides toward the aliphatic carbon of methyl p-nitrobenzenesulfonate (pNBS) was investigated by computer simulations. The calculations were performed by using a hybrid quantum-mechanical/molecular-mechanical (QM/MM) methodology. A semiempirical Hamiltonian was first parametrized on the basis of comparison with ab initio calculations for Cl(-) and Br(-) reaction with pNBS at gas phase. In condensed phase, free energy profiles were obtained for both reactions. The calculated reaction barriers are in agreement with experiment. The structure of species solvated by the ionic liquid was followed along the reaction progress from the reagents, through the transition state, to the final products. The simulations indicate that this substitution reaction in the ionic liquid is slower than in nonpolar molecular solvents proper to significant stabilization of the halide anion by the ionic liquid in comparison with the transition state with delocalized charge. Solute-solvent interactions in the first solvation shell contain several hydrogen bonds that are formed or broken in response to charge density variation along the reaction coordinate. The detailed structural analysis can be used to rationalize the design of new ionic liquids with tailored solvation properties. (c) 2008 American Institute of Physics.

Cultural meaning of quality of life: perspectives of Brazilian burn patients

Purpose. This study was designed to explore the cultural meaning and dimensions of quality of life from the perspective of Brazilian burn patients. Method. A qualitative research approach was used. Nineteen burn patients and their close relatives participated in this ethnographic study. Data were collected by means of direct observation and semi-structured interviews, conducted in a hospital outpatient clinic and during visits to patients` homes. The following inter-related phases guided the analysis process: reading of the material and data reduction, data display, conclusion outlining and verification. Results. Participants reported that the quality of life is related to autonomy and the ability to work. The dimensions of quality of life included: resuming work and functional ability, body image, having leisure and interpersonal relationships. Their descriptions revealed their feelings and attitudes about resuming their previous activities and social lives, particularly concerning the work. Conclusion. For burn patients, quality of life is associated with the concept of normality, the satisfactory performance of social roles in the context of family life and the social world. The results showed the importance of the sociocultural dimension in the concept of quality of life for persons undergoing burn rehabilitation.

Effect of fibre morphology on flocculation of fibre-cement suspensions

The objective of the present research was to evaluate the effect of fibre morphology (e.g., length, width, fibrillation, broken ends, content of fines and number of fibres per gram) on flocculation and drainage properties of fibre-cement suspensions and on physical properties of the fibre-cement composites. Mechanical refining was used to change the morphological properties of Eucalyptus and Pinus pulps. Results show that the mechanical refining increased the size of the formed flocs and decreased the concentration of free small particles (with dimensions between 1 and 20 pm) as a consequence of the increased fibrillation and content of fines, which increased the capacity of the fibres to capture the mineral particles. High levels of refining were necessary for Pinus pulp to obtain cement retention values similar to those obtained by unrefined Eucalyptus pulp. This is due to the higher number of fibres per gram in Eucalyptus pulp than in Pinus pulp. Pulp refining improved the packing of the particles and, although decreased the drainage rate. it contributed to a less porous structure, which improved the microstructure of the composite. (C) 2009 Elsevier Ltd. All rights reserved.

Post-failure behaviour of impulsively loaded circular plates

The dynamic plastic response of a simply supported circular plate is analysed. Emphasis is given to the plate behaviour after it has broken free from the supports due to a local material failure. The theoretical rigid plastic analysis predicts various features of the response such as the time to failure, residual kinetic energy and the critical velocity at failure. The residual kinetic energy of the plate could be significant enough to cause secondary impact damage. It is shown that the shape of the plate changes after breaking free from the supports, which is important for forensic investigations. The solution for various cases were proven to be exact in the context of the upper and lower bounds theorems of the theory of plasticity. (C) 2009 Elsevier Ltd. All rights reserved.

Who should wear mask against airborne infections? Altering the contact network for controlling the spread of contagious diseases

There are several ways of controlling the propagation of a contagious disease. For instance, to reduce the spreading of an airborne infection, individuals can be encouraged to remain in their homes and/or to wear face masks outside their domiciles. However, when a limited amount of masks is available, who should use them: the susceptible subjects, the infective persons or both populations? Here we employ susceptible-infective-recovered (SIR) models described in terms of ordinary differential equations and probabilistic cellular automata in order to investigate how the deletion of links in the random complex network representing the social contacts among individuals affects the dynamics of a contagious disease. The inspiration for this study comes from recent discussions about the impact of measures usually recommended by health public organizations for preventing the propagation of the swine influenza A (H1N1) virus. Our answer to this question can be valid for other eco-epidemiological systems. (C) 2010 Elsevier BM. All rights reserved.

Growth performance and body composition of pacu Piaractus mesopotamicus (Holmberg 1887) in response to dietary protein and energy levels

Improper dietary protein and energy levels and their ratio will lead to increased fish production cost. This work evaluated effects of dietary protein : energy ratio on growth and body composition of pacu, Piaractus mesopotamicus. Fingerling pacu (15.5 +/- 0.4 g) were fed twice a day for 10 weeks until apparent satiation with diets containing 220, 260, 300, 340 or 380 g kg-1 crude protein (CP) and 10.9, 11.7, 12.6, 13.4 or 14.2 MJ kg-1 digestible energy (DE) in a totally randomized experimental design, 5 x 5 factorial scheme (n = 3). Weight gain, specific growth rate increased and feed conversion ratio (FCR) decreased significantly (P < 0.05) when CP increased from 220 to 271, 268 and 281 g kg-1 respectively. Pacu was able to adjust feed consumption in a wide range of dietary DE concentration. Fish fed 260 CP diets showed best (P < 0.05) protein efficiency ratio and FCR with 11.7-12.6 MJ kg-1; but for the 380 CP-diets group, significant differences were observed only at 14.2 MJ kg-1 dietary energy level, suggesting that pacu favours protein as energy source. DE was the chief influence on whole body chemical composition. Minimum dietary protein requirement of pacu is 270 g kg-1, with an optimum CP : DE of 22.2 g MJ-1.

Growth and haematology of pacu, Piaractus mesopotamicus, fed diets with varying protein to energy ratio

Haematopoiesis and blood cells` functions can be influenced by dietary concentration of nutrients. This paper studied the effects of dietary protein:energy ratio on the growth and haematology of pacu, Piaractus mesopotamicus. Fingerling pacu (15.5 +/- 0.4 g) were fed twice a day for 10 weeks until apparent saciety with diets containing 220, 260, 300, 340 or 380 g kg(-1) crude protein (CP) and 10.88, 11.72, 12.55, 13.39, 14.22 MJ kg(-1) digestible energy (DE) in a totally randomized experimental design, 5 x 5 factorial scheme (n=3). Weight gain and specific growth rate were affected (P < 0.05) by protein level only. Protein efficiency ratio decreased (P < 0.05) with increasing dietary protein at all levels of dietary energy. Daily feed intake decreased (P < 0.05) with increasing dietary energy. Mean corpuscular haemoglobin concentration was affected (P < 0.05) by DE and interaction between dietary CP and DE. Total plasma protein increased (P < 0.05) with dietary protein and energy levels. Plasma glucose decreased (P < 0.05) with increasing dietary protein. The CP requirement and optimum protein:energy ratio for weight gain of pacu fingerlings, determined using broken-line model, were 271 g kg(-1) and 22.18 g CP MJ(-1) DE respectively. All dietary CP and DE levels studied did not pose damages to fish health.

Residential high-rise buildings in São Paulo: aspects related to the adequacy to the occupant`s needs

This paper analyzes the production of apartment buildings for the middle-income segment in the city of So Paulo, Brazil, from a historical perspective. Tracing the response to the occupants` needs, the focus is on family profiles and their demands, the relationship between architectural design and marketing, and satisfaction levels of current users. The paper begins with a brief historical overview of how apartment buildings have evolved over the past eight decades, highlighting the consolidation of the tripartite model. Next, it analyzes family profiles and their current needs, which would call for a redesign of domestic space. From a different angle, it shows how the real-estate market reacts to this situation, namely by introducing minor changes in the domestic space that are closely linked to major investments in marketing. This leads to a discussion on the quality of recent architectural designs in light of Post-Occupancy Evaluation (POE) case studies, which corroborate the tendencies previously outlined. The conclusions drawn from the POEs suggest that the market should establish a closer and deeper relationship between the assessment of the human behavior in the domestic space and the architectural quality of homes as a means of increasing satisfaction levels and improving design performance.

Evaluation of physico-chemical and phytochemical characteristics of different tinctures of barbatimao (Stryphnodendron barbatiman)

As a consequence of the large distribution and use of medicinal plants, the industries are producing products based on plant species in various pharmaceutical forms, which have been commercialized in pharmacies and natural products homes. However, there is no guarantee for the vast majority of these products, as to their effctiveness, safety, and quality, which may cause risks to the health of consumers. There it is important the establishment of standardized protocols of quality control for phytotherapeutic products. Tinctures of barbatimao are available in the Brazilian market proceeding from diverse manufacturers. With the purpose to evaluate the difference between the quality of tinctures of barbatimao proceeding from four manufactures, a comparative study of ph ysico-chenfical andphylocheinical characteristics was carried out. For physico-chemical analysis, the pH, density, dry residue and tannins content were evaluated. The phytochemical analysis was made using thin layer chromatography. The differences observed in physico-chemical and phytochemical characteristics had evidenced the lack of standardization in the production of these tinctures.