Peso al nacer de niños brasileños menores de dos años

Low birth weight is associated with increased risk of dying in the first year of life. This study was motivated by recent changes in the determination of birth weight patterns with the advent of the perinatal epidemiological transition. We analyzed data from the Brazilian National Survey of Demographic and Health of Children and Women including only children < 24 months. Prevalence of low birth weight in Brazil was 6.1%. Risk factors included female gender, residence in the South and Southeast geographic regions, low maternal education, and maternal smoking. The low birth weight profile changed, with higher prevalence in more economically developed regions, reflecting the neonatal epidemiological transition determined by changes in patterns of childbirth care and incorporation of perinatal life support technologies, in addition to the previously known biological risks associated with poverty and misinformation.El bajo peso al nacer tiene una gran relación con el riesgo de morir en el primer año de vida. Estudios muestran su asociación con problemas de desarrollo en la infancia y enfermedades en la vida adulta. Dada la importancia de este indicador, el objetivo de este estudio fue investigar los factores sociales, demográficos, biológicos y ambientales involucrados en su determinación. Se analizaron los datos de la Investigación Nacional de Demografía y Salud del Niño y de la Mujer (PNDS-2006), incluyendo solamente niños menores de 24 meses de vida. La prevalencia de bajo peso al nacer en Brasil fue de un 6,1%. Los factores de riesgo identificados fueron sexo femenino, residir en las macrorregiones Sur y Sudeste y ser hijo de madres con baja escolaridad o tabaquistas. Hubo cambios en el perfil de bajo peso al nacer, con mayor prevalencia en regiones más desarrolladas económicamente, reflejando la transición epidemiológica perinatal, caracterizada por cambios en los padrones de asistencia al parto e incorporación de los avances tecnológicos en la asistencia perinatal, además de factores de riesgo biológicos conocidos, asociados a la pobreza y a la desinformación.O baixo peso ao nascer tem grande relação com risco de morrer no primeiro ano de vida. Estudos mostram sua associação com problemas de desenvolvimento na infância e doenças na vida adulta. Dada a importância desse indicador, o objetivo deste estudo foi investigar os fatores sociais, demográficos, biológicos e ambientais envolvidos na sua determinação. Analisaram-se dados da Pesquisa Nacional de Demografia e Saúde da Criança e da Mulher (PNDS-2006), incluindo apenas crianças menores de 24 meses de vida. A prevalência de baixo peso ao nascer no Brasil foi de 6,1%. Os fatores de risco identificados foram sexo feminino, residir nas macrorregiões Sul e Sudeste e ser filho de mães com baixa escolaridade ou tabagistas. Houve mudanças no perfil do baixo peso ao nascer, com maior prevalência em regiões mais desenvolvidas economicamente, refletindo a transição epidemiológica perinatal, caracterizada por mudanças nos padrões de assistência ao parto e incorporação dos avanços tecnológicos na assistência perinatal, além de fatores de risco biológicos conhecidos associados à pobreza e à desinformação.Universidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

Characteristic Potentials for Mesoscopic Rings Threaded by an Aharonov-Bohm Flux

Electro-static potentials for samples with the topology of a ring and penetrated by an Aharonov-Bohm flux are discussed. The sensitivity of the electron-density distribution to small variations in the flux generates an effective electro-static potential which is itself a periodic function of flux. We investigate a simple model in which the flux sensitive potential leads to a persistent current which is enhanced compared to that of a loop of non-interacting electrons. For sample geometries with contacts the sensitivity of the electro-static potential to flux leads to a flux-induced capacitance. This capacitance gives the variation in charge due to an increment in flux. The flux-induced capacitance is contrasted with the electro-chemical capacitance which gives the variation in charge due to an increment in an electro-chemical potential. The discussion is formulated in terms of characteristic functions which give the variation of the electro-static potential in the interior of the conductor due to an increment in the external control parameters (flux, electro-chemical potentials). Paper submitted to the 16th Nordic Semiconductor Meeting, Laugarvatan, Iceland, June 12-15, 1994. The proceedings will be published in Physica Scripta.Comment: 23 pages + 4 figures, revtex, IBM-RC1955

Patient Diagnostic Rate as Indicator of Tuberculosis Case Detection, South Africa.

To address the uncertainty of the indirectly measured tuberculosis case detection rate, we used survey data stratified by HIV status to calculate the patient diagnostic rate, a directly measurable indicator, in 8 communities in South Africa. Rates were lower among HIV-negative than HIV-positive persons. Tuberculosis programs should focus on HIV-negative persons

Comparing laboratory costs of smear/culture and Xpert(®) MTB/RIF-based tuberculosis diagnostic algorithms

SETTING: Cape Town, South Africa, where Xpert® MTB/RIF was introduced as a screening test for all presumptive tuberculosis (TB) cases. OBJECTIVE: To compare laboratory costs of smear/culture- and Xpert-based tuberculosis (TB) diagnostic algorithms in routine operational conditions. METHODS: Economic costing was undertaken from a laboratory perspective, using an ingredients-based costing approach. Cost allocation was based on reviews of standard operating procedures and laboratory records, timing of test procedures, measurement of laboratory areas and manager interviews. We analysed laboratory test data to assess overall costs and cost per pulmonary TB and multidrug-resistant TB (MDR-TB) case diagnosed. Costs were expressed as 2013 Consumer Price Index-adjusted values. RESULTS: Total TB diagnostic costs increased by 43%, from US$440 967 in the smear/culture-based algorithm (April–June 2011) to US$632 262 in the Xpert-based algorithm (April–June 2013). The cost per TB case diagnosed increased by 157%, from US$48.77 (n = 1601) to US$125.32 (n = 1281). The total cost per MDR-TB case diagnosed was similar, at US$190.14 and US$183.86, with 95 and 107 cases diagnosed in the respective algorithms. CONCLUSION: The introduction of the Xpert-based algorithm resulted in substantial cost increases. This was not matched by the expected increase in TB diagnostic efficacy, calling into question the sustainability of this expensive new technology

Transport Properties of a One-Dimensional Two-Component Quantum Liquid with Hyperbolic Interactions

We present an investigation of the sinh-cosh (SC) interaction model with twisted boundary conditions. We argue that, when unlike particles repel, the SC model may be usefully viewed as a Heisenberg-Ising fluid with moving Heisenberg-Ising spins. We derive the Luttinger liquid relation for the stiffness and the susceptibility, both from conformal arguments, and directly from the integral equations. Finally, we investigate the opening and closing of the ground state gaps for both SC and Heisenberg-Ising models, as the interaction strength is varied.Comment: 10 REVTeX pages + 4 uuencoded figures, UoU-002029

The use of a geographical information system (GIS) to evaluate the distribution of tuberculosis in a high-incidence community

CITATION: Beyers, N. et al. 1996. The use of a geographical information system (GIS) to evaluate the distribution of tuberculosis in a high-incidence community. South African Medical Journal, 86(1):40-44.The original publication is available at http://www.samj.org.zaObjective. To determine the geographical distribution of tuberculosis in the two Western Cape suburbs with the highest reported incidence of tuberculosis. Design. Descriptive illustrative study. Setting. Two adjacent Western Cape suburbs covering 2.42 km2 with a population of 34 294 and a reported tuberculosis incidence of > 1 000/100 000. Subjects. All patients notified as having tuberculosis over a 10-year period (1985-1994). Interventions. None. Outcome measure. The geographical distribution of the cases was determined using a geographical information system (GIS) and the National Population Census (1991). Results. One thousand eight hundred and thirty-five of the 5 345 dwelling units (34.3%) housed at least 1 case of tuberculosis during the past decade and in 483 houses 3 or more cases occurred. These cases were distributed unevenly through the community, with the tuberculosis incidence per enumerator subdistrict (ESD) varying from 78 to 3 150/100 000 population. Conclusion. In a small area with a high incidence of tuberculosis, the cases are spread unevenly through the community and there are certain houses where tuberculosis occurs repeatedly. This information should be used to direct health services to concentrate on certain high-risk areas.Publisher’s versio

Systematic behaviour of the in-plane penetration depth in d-wave cuprates

We report the temperature T and oxygen concentration dependences of the penetration depth of grain-aligned YBa_2Cu_3O_{7-\delta} with \delta= 0.0, 0.3 and 0.43. The values of the in-plane \lambda_{ab}(0) and out-of-plane \lambda_{c}(0) penetration depths, the low temperature linear term in \lambda_{ab}(T), and the ratio \lambda_{c}(0) /\lambda_{ab}(T) were found to increase with increasing $\delta$. The systematic changes of the linear term in \lambda_{ab}(T) with T_c found here and in recent work on HgBa_2Ca_{n-1} Cu_nO_{2n+2+\delta} (n = 1 and 3) are discussed.Comment: 4 pages, 4 figure

Correlated local distortions of the TlO layers in Tl2_2Ba2_2CuOy_{y}: An x-ray absorption study

We have used the XAFS (x-ray-absorption fine structure) technique to investigate the local structure about the Cu, Ba, and Tl atoms in orthorhombic Tl-2201 with a superconducting transition temperature T$_c$=60 K. Our results clearly show that the O(1), O(2), Cu, and Ba atoms are at their ideal sites as given by the diffraction measurements, while the Tl and O(3) atoms are more disordered than suggested by the average crystal structure. The Tl-Tl distance at 3.5 \AA{ } between the TlO layers does not change, but the Tl-Tl distance at 3.9 \AA{ } within the TlO layer is not observed and the Tl-Ba and Ba-Tl peaks are very broad. The shorter Tl-O(3) distance in the TlO layer is about 2.33 \AA, significantly shorter than the distance calculated with both the Tl and O(3) atoms at their ideal $4e$ sites ( $x=y=$0 or $\frac{1}{2}$). A model based on these results shows that the Tl atom is displaced along the directions from its ideal site by about 0.11 \AA; the displacements of neighboring Tl atoms are correlated. The O(3) atom is shifted from the $4e$ site by about 0.53 \AA{ } roughly along the directions. A comparison of the Tl L$_{III}$-edge XAFS spectra from three samples, with T$_c$=60 K, 76 K, and 89 K, shows that the O environment around the Tl atom is sensitive to T$_c$ while the Tl local displacement is insensitive to T$_c$ and the structural symmetry. These conclusions are compared with other experimental results and the implications for charge transfer and superconductivity are discussed. This paper has been submitted to Phys. Rev. B.Comment: 20 pages plus 14 ps figures, REVTEX 3.