104 research outputs found

    Side effects and the need for secrecy: characterising discontinuation of modern contraception and its causes in Ethiopia using mixed methods

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    Background: Contraceptive discontinuation is a major barrier to reducing global unmet needs for family planning, but the reasons why women discontinue contraception are poorly understood. Here we use data from Ethiopia to investigate (i) the magnitude of contraceptive discontinuation in 2005-2011, (ii) how the risk of discontinuation varies with method type and education level and (iii) the barriers to continuation. Our main hypothesis is that contraceptive discontinuation is driven by the experience of physiological side-effects associated with the use of hormonal contraception, rather than a lack of formal education. Methods: We used a mixed methods explanatory sequential design to explain the quantitative results in more details through the qualitative data. First, we analysed quantitative data from the 2011 Ethiopian Demographic and Health Survey to study patterns of contraceptive discontinuation and method choice using multilevel multiprocess models. Second, we conducted semi-structured interviews and focus group discussions in the 3 most populated regions of Ethiopia with individuals of reproductive age and health professionals. Results: The analysis of EDHS data shows that the rate of discontinuation has not reduced in the period 2005-2011 and remains high. Discontinuation mainly takes the form of abandonment, and is a function of method type, age and wealth but not of educational level. Interviews with women and health professionals reveal that the experience of debilitating physiological side effects, the need for secrecy and poverty are important barriers to continuation. Conclusions: Our findings together suggest that physiological and social side-effects of contraceptive use, not a lack of formal education, are the root causes of contraceptive abandonment in Ethiopia. </p

    Mesoporous Silica Nanoparticles Loaded with Surfactant: Low Temperature Magic Angle Spinning 13C and 29Si NMR Enhanced by Dynamic Nuclear Polarization

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    We show that dynamic nuclear polarization (DNP) can be used to enhance NMR signals of13C and 29Si nuclei located in mesoporous organic/inorganic hybrid materials, at several hundreds of nanometers from stable radicals (TOTAPOL) trapped in the surrounding frozen disordered water. The approach is demonstrated using mesoporous silica nanoparticles (MSN), functionalized with 3-(N-phenylureido)propyl (PUP) groups, filled with the surfactant cetyltrimethylammonium bromide (CTAB). The DNP-enhanced proton magnetization is transported into the mesopores via 1H–1H spin diffusion and transferred to rare spins by cross-polarization, yielding signal enhancements εon/off of around 8. When the CTAB molecules are extracted, so that the radicals can enter the mesopores, the enhancements increase to εon/off ≈ 30 for both nuclei. A quantitative analysis of the signal enhancements in MSN with and without surfactant is based on a one-dimensional proton spin diffusion model. The effect of solvent deuteration is also investigated

    Suppression of grasshopper sound production by nitric oxide-releasing neurons of the central complex

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    The central complex of acridid grasshoppers integrates sensory information pertinent to reproduction-related acoustic communication. Activation of nitric oxide (NO)/cyclic GMP-signaling by injection of NO donors into the central complex of restrained Chorthippus biguttulus females suppresses muscarine-stimulated sound production. In contrast, sound production is released by aminoguanidine (AG)-mediated inhibition of nitric oxide synthase (NOS) in the central body, suggesting a basal release of NO that suppresses singing in this situation. Using anti-citrulline immunocytochemistry to detect recent NO production, subtypes of columnar neurons with somata located in the pars intercerebralis and tangential neurons with somata in the ventro-median protocerebrum were distinctly labeled. Their arborizations in the central body upper division overlap with expression patterns for NOS and with the site of injection where NO donors suppress sound production. Systemic application of AG increases the responsiveness of unrestrained females to male calling songs. Identical treatment with the NOS inhibitor that increased male song-stimulated sound production in females induced a marked reduction of citrulline accumulation in central complex columnar and tangential neurons. We conclude that behavioral situations that are unfavorable for sound production (like being restrained) activate NOS-expressing central body neurons to release NO and elevate the behavioral threshold for sound production in female grasshoppers

    Dynamic Nuclear Polarization NMR Spectroscopy Allows High-Throughput Characterization of Microporous Organic Polymers

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    Dynamic nuclear polarization (DNP) solid-state NMR was used to obtain natural abundance 13C and 15N CP MAS NMR spectra of microporous organic polymers with excellent signal-to-noise ratio, allowing for unprecedented details in the molecular structure to be determined for these complex polymer networks. Sensitivity enhancements larger than 10 were obtained with bis-nitroxide radical at 14.1 T and low temperature (∼105 K). This DNP MAS NMR approach allows efficient, high-throughput characterization of libraries of porous polymers prepared by combinatorial chemistry methods

    Maternal High Fat Diet Is Associated with Decreased Plasma n–3 Fatty Acids and Fetal Hepatic Apoptosis in Nonhuman Primates

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    To begin to understand the contributions of maternal obesity and over-nutrition to human development and the early origins of obesity, we utilized a non-human primate model to investigate the effects of maternal high-fat feeding and obesity on breast milk, maternal and fetal plasma fatty acid composition and fetal hepatic development. While the high-fat diet (HFD) contained equivalent levels of n-3 fatty acids (FA's) and higher levels of n-6 FA's than the control diet (CTR), we found significant decreases in docosahexaenoic acid (DHA) and total n-3 FA's in HFD maternal and fetal plasma. Furthermore, the HFD fetal plasma n-6∶n-3 ratio was elevated and was significantly correlated to the maternal plasma n-6∶n-3 ratio and maternal hyperinsulinemia. Hepatic apoptosis was also increased in the HFD fetal liver. Switching HFD females to a CTR diet during a subsequent pregnancy normalized fetal DHA, n-3 FA's and fetal hepatic apoptosis to CTR levels. Breast milk from HFD dams contained lower levels of eicosopentanoic acid (EPA) and DHA and lower levels of total protein than CTR breast milk. This study links chronic maternal consumption of a HFD with fetal hepatic apoptosis and suggests that a potentially pathological maternal fatty acid milieu is replicated in the developing fetal circulation in the nonhuman primate

    The 4D nucleome project

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    The genus Neocypholaelaps

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