5,079 research outputs found

    Why do women deliver where they had not planned to go? A qualitative study from peri-urban Nairobi Kenya.

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    BACKGROUND: In urban Kenya, couples face a wide variety of choices for delivery options; however, many women end up delivering in different facilities from those they had intended while pregnant. One potential consequence of this is delivering in facilities that do not meet minimum quality standards and lack the capacity to provide treatment for obstetric and neonatal complications. METHODS: This study investigated why women in peri-urban Nairobi, Kenya deliver in facilities they had not intended to use. We used 60 in-depth audio-recorded interviews in which mothers shared their experiences 2-6ā€‰months after delivery. Descriptive statistics were used to summarize socio-demographic characteristics of participants. Qualitative data were analyzed in three steps i) exploration and generation of initial codes; ii) searching for themes by gathering coded data that addressed specific themes; and iii) defining and naming identified themes. Verbatim excerpts from participants were provided to illustrate study findings. The Health Belief Model was used to shed light on individual-level drivers of delivery location choice. RESULTS: Findings show a confluence of factors that predispose mothers to delivering in unintended facilities. At the individual level, precipitate labor, financial limitations, onset of pain, complications, changes in birth plans, undisclosed birth plans, travel during pregnancy, fear of health facility providers, misconception of onset of labor, wrong estimate of delivery date, and onset of labor at night, contributed to delivery at unplanned locations. On the supply side, the sudden referral to other facilities, poor services, wrong projection of delivery date, and long distance to chosen delivery facility, were factors in changes in delivery location. Lack of transport discouraged delivery at a chosen health facility. Social influences included others\u27 perspectives on delivery location and lack of aides/escorts. CONCLUSIONS: Results from this study suggest that manifold factors contribute to the occurrence of women delivering in facilities that they had not intended during pregnancy. Future studies should consider whether these changes in delivery location late in pregnancy contribute to late facility arrival and the use of lower quality facilities. Deliberate counseling during antenatal care regarding birth plans is likely to encourage timely arrival at facilities consistent with women\u27s preferences

    Design features and results from fatigue reliability research machines

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    Design and performance tests for reversed bending with steady torque fatigue test machine using notched steel specimen

    Quantum Drinfeld Hecke Algebras

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    We consider finite groups acting on quantum (or skew) polynomial rings. Deformations of the semidirect product of the quantum polynomial ring with the acting group extend symplectic reflection algebras and graded Hecke algebras to the quantum setting over a field of arbitrary characteristic. We give necessary and sufficient conditions for such algebras to satisfy a Poincare-Birkhoff-Witt property using the theory of noncommutative Groebner bases. We include applications to the case of abelian groups and the case of groups acting on coordinate rings of quantum planes. In addition, we classify graded automorphisms of the coordinate ring of quantum 3-space. In characteristic zero, Hochschild cohomology gives an elegant description of the Poincare-Birkhoff-Witt conditions.Comment: 29 pages. Last example corrected; some indices in the last theorem were accidentally transposed and now appear in correct orde

    Bayesian multiscale deconvolution applied to gamma-ray spectroscopy

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    A common task in gamma-ray astronomy is to extract spectral information, such as model constraints and incident photon spectrum estimates, given the measured energy deposited in a detector and the detector response. This is the classic problem of spectral ā€œdeconvolutionā€ or spectral inversion. The methods of forward folding (i.e., parameter fitting) and maximum entropy ā€œdeconvolutionā€ (i.e., estimating independent input photon rates for each individual energy bin) have been used successfully for gamma-ray solar flares (e.g., Rank, 1997; Share and Murphy, 1995). These methods have worked well under certain conditions but there are situations were they donā€™t apply. These are: 1) when no reasonable model (e.g., fewer parameters than data bins) is yet known, for forward folding; 2) when one expects a mixture of broad and narrow features (e.g., solar flares), for the maximum entropy method; and 3) low count rates and low signal-to-noise, for both. Low count rates are a problem because these methods (as they have been implemented) assume Gaussian statistics but Poisson are applicable. Background subtraction techniques often lead to negative count rates. For Poisson data the Maximum Likelihood Estimator (MLE) with a Poisson likelihood is appropriate. Without a regularization term, trying to estimate the ā€œtrueā€ individual input photon rates per bin can be an ill-posed problem, even without including both broad and narrow features in the spectrum (i.e., amultiscale approach). One way to implement this regularization is through the use of a suitable Bayesian prior. Nowak and Kolaczyk (1999) have developed a fast, robust, technique using a Bayesian multiscale framework that addresses these problems with added algorithmic advantages. We outline this new approach and demonstrate its use with time resolved solar flare gamma-ray spectroscopy

    COMPTEL observations of the Virgo blazars 3C 273 and 3C 279

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    We report the main MeV properties (detections, light curves, spectra) of the Virgo blazars 3C 273 and 3C 279 which were derived from a consistent analysis of all COMPTEL Virgo observations between 1991 and 1997

    COMPTEL observations of the blazars 3C 454.3 and CTA 102

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    We have analyzed the two blazars of 3C 454.3 and CTA 102 using all available COMPTEL data from 1991 to 1999. In the 10ā€“30 MeV band, emission from the general direction of the sources is found at the 4Ļƒ-level, being consistent with contributions from both sources. Below 10 MeV only 3C 454.3 is significantly detected, with the strongest evidence (5.6 Ļƒ) in the 3ā€“10 MeV band. Significant flux variability is not observed for both sources, while a low emission is seen most of the years in the 3ā€“10 MeV light curve for 3C 454.3. Its time-averaged MeV spectrum suggests a power maximum between 3 to 10 MeV

    Generalized Weyl algebras and diskew polynomial rings

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    The aim of the paper is to extend the class of generalized Weyl algebras (GWAs) to a larger class of rings (they are also called GWAs) that are determined by two ring endomorphisms rather than one as in the case of ā€˜oldā€™ GWAs. A new class of rings, the diskew polynomial rings, is introduced that is closely related to GWAs (they are GWAs under a mild condition). Simplicity criteria are given for GWAs and diskew polynomial rings

    Energetic proton spectra in the 11 June 1991 solar flare

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    We have studied a subset of the 11 June 1991 solar flare Ī³-ray data that we believe arise from soft proton or ion spectra. Using data from the COMPTEL instrument on the Compton Observatory we discuss the gamma-ray intensities at 2.223 MeV, 4ā€“7 MeV, and 8ā€“30 MeV in terms of the parent proton spectrum responsible for the emission

    Complex Susceptibility of Liquid Water as a Two-Potential System of Reorienting Polar Molecules

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    The theory elaborated in ref. 1 and 2 is applied to the calculation of the liquid water wide-band (0 < Ī½/cm^(-1) < 1000) dielectric spectra. These comprise the Debye relaxation region at the centimetre/millimetre wavelengths and the two-humped absorption coefficient frequency dependence in the far infrared (FIR) region. It is supposed that a major part of H2O molecules, called [L]-particles or [L]-molecules, are bonded by relatively strong H-bonds; [L]-molecules perform librations of relatively small amplitude Ī² (Ī² is about 20Ā°). The remaining molecules called R-molecules have more rotational / translational mobility. A new microscopic molecular confined rotator / doble well potential (CR DWP) model of liquid water is developed. The contributions of [L]-and [R]-molecules to the complex permittivity Īµ are found on the basis of the confined rotator (CR) and the double well potential (DWP) models, with rectangular and cos^2(Īø) intermolecular potential profiles, respectively. It is shown that the CR/DWP model gives a good description of the Debye relaxation and a qualitative description of FIR the dielectric spectra of water
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