Declared Maternal Death And The Linkage Between Health Information Systems

Objective: To describe the characteristics of maternal mortality according to the Mortality Information System in relation to the data corresponding to these records that are in other systems. Methods: This was a descriptive study using two information systems on vital data and another on the hospital system, for the 26 state capitals and the Federal District of Brazil, in 2002. Initially, the maternal mortality ratios were calculated and information on declared maternal deaths were obtained. From these data, the Mortality Information System was probabilistically linked with the Live Birth Information System and the Hospital Information System, using the "Reclink II" software, with a multiple-step blocking strategy. For paired records, the diagnoses and hospital procedures brought together by the best-known criteria for severe maternal morbidity were detailed. Results: A total of 339 maternal deaths were recorded in 2002. The official and adjusted maternal mortality ratios were, respectively, 46.4 and 64.9 (deaths per 100,000 live births). By correlating with data from the live birth system, 46.5% of the maternal deaths could be located; and from the hospital information, 55.2%. The most frequent admission diagnosis was infection (13.9%) and the most frequent procedure was intensive care unit admission (39.0%). Conclusions: There were low percentage linkages between the records from the three sources studied. However, the possible failures and/or impossibilities in the linkages indicated may separately or jointly explain these low percentages.412181189AbouZahr, C., Wardlaw, T., (2003) Maternal mortality in 2000: Estimates developed by WHO, , Unicef and UNFPA. Geneva: WHO;Camargo Jr, K.R., Coeli, C.M., Reclink: Aplicativo para o relacionamento de bases de dados, implementando o método probabilistic record linkage (2000) Cad Saúde Pública, 16 (2), pp. 439-447Cecatti, J.G., Faúndes, A., Surita, F.C.C., Maternal mortality in Campinas: Evolution, under-registration and avoidance (1999) São Paulo Med J, 117 (1), pp. 5-12Coeli, C.M., Camargo Jr, K.R., Avaliação de diferentes estratégias de blocagem no relacionamento probabilístico de registros (2002) Rev Bras Epidemiol, 5 (2), pp. 185-196Coeli, C.M., Costa, M.C.E., Almeida, L.M., Probabilistic linkage in household survey on hospital care usage (2003) Rev Saúde Pública, 37 (1), pp. 91-99Fleiss, J.L., (1981) Statistical methods for rates and proportions, , 2nd ed. New York: John Wiley and Sons;Jaro, M.A., Advances in record-linkage methodology as applied to matching the 1985 Census of Tampa, Florida (1989) J Am Stat Assoc, 84, pp. 414-420Laurenti, R., Mello-Jorge, M.H.P., Gotlieb, S.L.D., Reflexões sobre a mensuração da mortalidade materna (2000) Cad Saúde Pública, 16 (1), pp. 23-30Laurenti, R., Mello-Jorge, M.H.P., Gotlieb, S.L.D., A mortalidade materna nas capitais brasileiras: Algumas características e estimativa de um fator de ajuste (2004) Rev Bras Epidemiol, 7 (4), pp. 449-460Machado, C.J., Hill, K., Probabilistic record linkage and an automated procedure to minimize the undecided-matched pair problem (2004) Cad Saúde Pública, 20 (4), pp. 915-925Mantel, G.D., Buchmann, E., Rees, H., Pattinson, R.C., Severe acute maternal morbidity: A pilot study of a definition for a near-miss (1998) Br J Obstet Gynaecol, 105 (9), pp. 985-990Royston, E., AbouZahr, C., Measuring maternal mortality (1992) Br J Obstet Gynaecol, 99, pp. 540-542Sousa, M.H., Cecatti, J.G., Hardy, H.E., Amaral, E., Souza, J.P.D., Serruya, S., Sistemas de informação em saúde e o monitoramento de morbidade materna grave e mortalidade materna (2006) Rev Bras Saúde Matern Infant, 6 (2), pp. 161-168Souza, J.P.D., Cecatti, J.G., Parpinelli, M.A., Sousa, M.H., Serruya, S., Revisão sistemática sobre morbidade materna near miss (2006) Cad Saúde Pública, 22 (2), pp. 255-264Theme Filha, M.M., Silva, R.I., Noronha, C.P., Mortalidade materna no município do Rio de Janeiro, 1993-1996 (1999) Cad Saúde Pública, 15 (2), pp. 397-403Waterstone, M., Bewley, S., Wolfe, C., Incidence and predictors of severe obstetric morbidity: Case-control study (2001) BMJ, 322 (7294), pp. 1089-1093(1999) Reduction of maternal mortality: A joint WHO/UNFPA/Unicef World Bank Statement, , World Health Organization, Geneva;(2004) Beyond the numbers: Reviewing maternal deaths and complications to make pregnancy safer, , World Health Organization, Geneva

The Origin of Magnetic Interactions in Ca3Co2O6

We investigate the microscopic origin of the ferromagnetic and antiferromagnetic spin exchange couplings in the quasi one-dimensional cobalt compound Ca3Co2O6. In particular, we establish a local model which stabilizes a ferromagnetic alignment of the S=2 spins on the cobalt sites with trigonal prismatic symmetry, for a sufficiently strong Hund's rule coupling on the cobalt ions. The exchange is mediated through a S=0 cobalt ion at the octahedral sites of the chain structure. We present a strong coupling evaluation of the Heisenberg coupling between the S=2 Co spins on a separate chain. The chains are coupled antiferromagnetically through super-superexchange via short O-O bonds.Comment: 5 Pages, 3 Figures; added anisotropy term in eq. 9; extended discussion of phase transitio

Unitarity as preservation of entropy and entanglement in quantum systems

The logical structure of Quantum Mechanics (QM) and its relation to other fundamental principles of Nature has been for decades a subject of intensive research. In particular, the question whether the dynamical axiom of QM can be derived from other principles has been often considered. In this contribution, we show that unitary evolutions arise as a consequences of demanding preservation of entropy in the evolution of a single pure quantum system, and preservation of entanglement in the evolution of composite quantum systems.Comment: To be submitted to the special issue of Foundations of Physics on the occassion of the seventieth birthday of Emilio Santos. v2: 10 pages, no figures, RevTeX4; Corrected and extended version, containing new results on consequences of entanglement preservatio

Weak Transitions in A=6 and 7 Nuclei

The $^6$He beta decay and $^7$Be electron capture processes are studied using variational Monte Carlo wave functions, derived from a realistic Hamiltonian consisting of the Argonne $v_{18}$ two-nucleon and Urbana-IX three-nucleon interactions. The model for the nuclear weak axial current includes one- and two-body operators with the strength of the leading two-body term--associated with $\Delta$-isobar excitation of the nucleon--adjusted to reproduce the Gamow-Teller matrix element in tritium $\beta$-decay. The measured half-life of $^6$. He is under-predicted by theory by $\simeq$ 8%, while that of $^7$Be for decay into the ground and first excited states of $^7$Li is over-predicted by $\simeq$ 9%. However, the experimentally known branching ratio for these latter processes is in good agreement with the calculated value. Two-body axial current contributions lead to a $\simeq$ 1.7% (4.4%) increase in the value of the Gamow-Teller matrix element of $^6$He ($^7$Be), obtained with one-body currents only, and slightly worsen (appreciably improve) the agreement between the calculated and measured half-life. Corrections due to retardation effects associated with the finite lepton momentum transfers involved in the decays, as well as contributions of suppressed transitions induced by the weak vector charge and axial current operators, have also been calculated and found to be negligible.Comment: 23 pages 8 tables. submitted to Phys. Rev.

Impacts of Climate Change on indirect human exposure to pathogens and chemicals from agriculture

Objective: Climate change is likely to affect the nature of pathogens and chemicals in the environment and their fate and transport. Future risks of pathogens and chemicals could therefore be very different from those of today. In this review, we assess the implications of climate change for changes in human exposures to pathogens and chemicals in agricultural systems in the United Kingdom and discuss the subsequent effects on health impacts. Data sources: In this review, we used expert input and considered literature on climate change ; health effects resulting from exposure to pathogens and chemicals arising from agriculture ; inputs of chemicals and pathogens to agricultural systems ; and human exposure pathways for pathogens and chemicals in agricultural systems. Data synthesis: We established the current evidence base for health effects of chemicals and pathogens in the agricultural environment ; determined the potential implications of climate change on chemical and pathogen inputs in agricultural systems ; and explored the effects of climate change on environmental transport and fate of different contaminant types. We combined these data to assess the implications of climate change in terms of indirect human exposure to pathogens and chemicals in agricultural systems. We then developed recommendations on future research and policy changes to manage any adverse increases in risks. Conclusions: Overall, climate change is likely to increase human exposures to agricultural contaminants. The magnitude of the increases will be highly dependent on the contaminant type. Risks from many pathogens and particulate and particle-associated contaminants could increase significantly. These increases in exposure can, however, be managed for the most part through targeted research and policy changes

Entangled-Photon Generation from Parametric Down-Conversion in Media with Inhomogeneous Nonlinearity

We develop and experimentally verify a theory of Type-II spontaneous parametric down-conversion (SPDC) in media with inhomogeneous distributions of second-order nonlinearity. As a special case, we explore interference effects from SPDC generated in a cascade of two bulk crystals separated by an air gap. The polarization quantum-interference pattern is found to vary strongly with the spacing between the two crystals. This is found to be a cooperative effect due to two mechanisms: the chromatic dispersion of the medium separating the crystals and spatiotemporal effects which arise from the inclusion of transverse wave vectors. These effects provide two concomitant avenues for controlling the quantum state generated in SPDC. We expect these results to be of interest for the development of quantum technologies and the generation of SPDC in periodically varying nonlinear materials.Comment: submitted to Physical Review

Physical properties of FeSe0.5_{0.5}Te0.5_{0.5} single crystals grown under different conditions

We report on structural, magnetic, conductivity, and thermodynamic studies of FeSe$_{0.5}$Te$_{0.5}$ single crystals grown by self-flux and Bridgman methods. The samples were prepared from starting materials of different purity at various temperatures and cooling rates. The lowest values of the susceptibility in the normal state, the highest transition temperature $T_c$ of 14.5 K, and the largest heat-capacity anomaly at $T_c$ were obtained for pure (oxygen-free) samples. The critical current density $j_c$ of $8 \times 10^4$ A/cm$^2$ (at 2 K) achieved in pure samples is attributed to intrinsic inhomogeneity due to disorder at the cation and anion sites. The impure samples show increased $j_c$ up to $2.3 \times 10^5$ A/cm$^2$ due to additional pinning centers of Fe$_3$O$_4$. The upper critical field $H_{c2}$ of $\sim 500$ kOe is estimated from the resistivity study in magnetic fields parallel to the \emph{c}-axis. The anisotropy of the upper critical field $\gamma_{H_{c2}} = H_{_{c2}}^{ab}/H_{_{c2}}^{c}$ reaches a value $\sim 6$ at $T\longrightarrow T_c$. Extremely low values of the residual Sommerfeld coefficient for pure samples indicate a high volume fraction of the superconducting phase (up to 97%). The electronic contribution to the specific heat in the superconducting state is well described within a single-band BCS model with a temperature dependent gap $\Delta_0 = 27(1)$ K. A broad cusp-like anomaly in the electronic specific heat of samples with suppressed bulk superconductivity is ascribed to a splitting of the ground state of the interstitial Fe$^{2+}$ ions. This contribution is fully suppressed in the ordered state in samples with bulk superconductivity.Comment: 11 pages, 11 figures, 3 table

A Real Space Description of Field Induced Melting in the Charge Ordered Manganites: II. the Disordered Case

We study the effect of A site disorder on magnetic field induced melting of charge order (CO) in half doped manganites using a Monte-Carlo technique. Strong A-site disorder destroys CO even without an applied field. At moderate disorder, the zero field CO state survives but has several intriguing features in its field response. Our spatially resolved results track the broadening of the field melting transition due to disorder and explain the unusual dependence of the melting scales on bandwidth and disorder. In combination with our companion paper on field melting of charge order in clean systems we provide an unified understanding of CO melting across all half doped manganites.Comment: 9 pages, pdflatex, 10 embedded png fig

A bootstrap method for sum-of-poles approximations

A bootstrap method is presented for finding efficient sum-of-poles approximations of causal functions. The method is based on a recursive application of the nonlinear least squares optimization scheme developed in (Alpert et al. in SIAM J. Numer. Anal. 37:1138–1164, 2000), followed by the balanced truncation method for model reduction in computational control theory as a final optimization step. The method is expected to be useful for a fairly large class of causal functions encountered in engineering and applied physics. The performance of the method and its application to computational physics are illustrated via several numerical examples

Quantum Locality

It is argued that while quantum mechanics contains nonlocal or entangled states, the instantaneous or nonlocal influences sometimes thought to be present due to violations of Bell inequalities in fact arise from mistaken attempts to apply classical concepts and introduce probabilities in a manner inconsistent with the Hilbert space structure of standard quantum mechanics. Instead, Einstein locality is a valid quantum principle: objective properties of individual quantum systems do not change when something is done to another noninteracting system. There is no reason to suspect any conflict between quantum theory and special relativity.Comment: Introduction has been revised, references added, minor corrections elsewhere. To appear in Foundations of Physic