Emergency contraception is using a drug or copper intrauterine device (Cu-IUD) to prevent pregnancy shortly after unprotected intercourse. Several interventions are available for emergency ...contraception. Information on the comparative efficacy, safety and convenience of these methods is crucial for reproductive health care providers and the women they serve.
To determine which emergency contraceptive method following unprotected intercourse is the most effective, safe and convenient to prevent pregnancy.
The search included the Cochrane Controlled Trials Register, Popline, MEDLINE, PubMed, Biosis/Embase, Chinese biomedical databases and UNDP/UNFPA/WHO/World Bank Special Programme on Human Reproduction (HRP) emergency contraception database (December 2006). Content experts and pharmaceutical companies were contacted.
Randomised controlled trials and controlled clinical trials including women attending services for emergency contraception following a single act of unprotected intercourse were eligible.
Data on outcomes and trial characteristics were extracted in duplicate and independently by two reviewers. Quality assessment was also done by two reviewers independently. Meta-analysis results are expressed as relative risk (RR) using a fixed-effects model with 95% confidence interval (CI). In the presence of statistically significant heterogeneity a random-effect model was applied.
Eighty-one trials with 45,842 women were included. Most trials were conducted in China (70/81). There were more pregnancies with levonorgestrel compared to mid-dose (25-50 mg) (15 trials, RR: 2.01; 95% CI: 1.27 to 3.17) or low-dose mifepristone (<25 mg) (9 trials, RR: 1.43; 95% CI: 1.02 to 2.01). Low-dose mifepristone was less effective than mid-dose (20 trials, RR:0.67; 95% CI: 0.49 to 0.92), but this effect was no longer statistically significant when only high quality trials were considered (6 trials, RR: 0.75; 95% CI: 0.50 to 1.10). Single dose levonorgestrel (1.5 mg) administration seemed to have similar effectiveness as the standard 12 hours apart split-dose (0.75 mg twice) (2 trials, 3830 women; RR: 0.77, 95% CI: 0.45 to 1.30). Levonorgestrel was more effective than the Yuzpe regimen in preventing pregnancy (2 trials, RR: 0.51; 95% CI: 0.31 to 0.83). CDB-2914 (a second-generation progesterone receptor modulator) may be as effective as levonorgestrel (1 trial, 1549 women; RR:1.89; 95% CI: 0.75 to 4.64) but the confidence interval is wide and the result compatible with higher or lower effectiveness. Delay in the onset of subsequent menses was the main unwanted effect of mifepristone and seemed to be dose-related.
Mifepristone middle dose (25-50 mg) was superior to other hormonal regimens. Mifepristone low dose (<25 mg) could be more effective than levonorgestrel 0.75 mg (two doses) but this was not conclusive. Levonorgestrel proved more effective than the Yuzpe regimen. The copper IUD was another effective emergency contraceptive that can provide ongoing contraception.
Highlights • Pain-related gamma responses can be recorded outside sensory cortices. • Pain-related gamma responses couple with the low-frequency theta and alpha. • Pain-related gamma responses are ...localized in the right limbic structures.
There are numerous reports regarding boron-containing catalysts for hydrogen-related reactions from CO2 including dry reforming of methane and methanation. Besides enhancing the productivity, boron ...also improved nickel activity and stability. However, the detailed mechanistic study, particularly in explaining the starring role of boron in the enhanced reactions, is still lacking. Thus, herein we loaded boron on fibrous-silica-nickel and investigated their physicochemical properties and mechanistic route by means of in-situ FTIR for enhanced CO2 methanation. It was found that the appropriate dispersion of boron surrounds the nickel particles is an important factor to improve the adsorption of CO2 before interacting with split hydrogen atom from the nickel sides to form intermediates which are subsequently dehydrated, and then serial hydrogenation gave the final product of methane. Boron also accelerated the methanation and restricted coke formation. A hybrid approach on optimization via a face-centered central composite design and a response surface methodology showed that reaction using H2/CO2 ratio of 6, GHSV of 10,500 mL g−1 h−1, at 500 °C gave the highest percentage of CH4 of 84.3%. To indicate the error, the predicted values were compared to the experimental values, yielding an accurately minimal error ranging from 0 to 11%. As a result, the empirical models generated for CO2 hydrogenation to methane were reasonably accurate, with all actual values for the confirmation runs fitting within the 94% prediction interval.
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•Apt boron dispersion surround nickel particles improved CO2 adsorption.•Boron accelerated the methanation and restricted the coke formation.•Addition of boron onto FSN improved the nickel activity and stability.•Optimization of methanation by FCCCD and RSM gave the highest 84.3% of methane.
ABSTRACT
We present in this paper one of the largest galaxy morphological classification catalogues to date, including over 20 million galaxies, using the Dark Energy Survey (DES) Year 3 data based ...on convolutional neural networks (CNNs). Monochromatic i-band DES images with linear, logarithmic, and gradient scales, matched with debiased visual classifications from the Galaxy Zoo 1 (GZ1) catalogue, are used to train our CNN models. With a training set including bright galaxies (16 ≤ i < 18) at low redshift (z < 0.25), we furthermore investigate the limit of the accuracy of our predictions applied to galaxies at fainter magnitude and at higher redshifts. Our final catalogue covers magnitudes 16 ≤ i < 21, and redshifts z < 1.0, and provides predicted probabilities to two galaxy types – ellipticals and spirals (disc galaxies). Our CNN classifications reveal an accuracy of over 99 per cent for bright galaxies when comparing with the GZ1 classifications (i < 18). For fainter galaxies, the visual classification carried out by three of the co-authors shows that the CNN classifier correctly categorizes discy galaxies with rounder and blurred features, which humans often incorrectly visually classify as ellipticals. As a part of the validation, we carry out one of the largest examinations of non-parametric methods, including ∼100 ,000 galaxies with the same coverage of magnitude and redshift as the training set from our catalogue. We find that the Gini coefficient is the best single parameter discriminator between ellipticals and spirals for this data set.
Highly oxygenated molecules (HOMs) play an important role in the formation and evolution of secondary organic aerosols (SOA). However, the abundance of HOMs in different environments and their ...relation to the oxidative potential of fine particulate matter (PM) are largely unknown. Here, we investigated the relative HOM abundance and radical yield of laboratory-generated SOA and fine PM in ambient air ranging from remote forest areas to highly polluted megacities. By electron paramagnetic resonance and mass spectrometric investigations, we found that the relative abundance of HOMs, especially the dimeric and low-volatility types, in ambient fine PM was positively correlated with the formation of radicals in aqueous PM extracts. SOA from photooxidation of isoprene, ozonolysis of α- and β-pinene, and fine PM from tropical (central Amazon) and boreal (Hyytiälä, Finland) forests exhibited a higher HOM abundance and radical yield than SOA from photooxidation of naphthalene and fine PM from urban sites (Beijing, Guangzhou, Mainz, Shanghai, and Xi’an), confirming that HOMs are important constituents of biogenic SOA to generate radicals. Our study provides new insights into the chemical relationship of HOM abundance, composition, and sources with the yield of radicals by laboratory and ambient aerosols, enabling better quantification of the component-specific contribution of source- or site-specific fine PM to its climate and health effects.
The LOng Range Reconnaissance Imager (LORRI) is a panchromatic (360-910 nm for the wavelengths where the responsivity falls to 10% of the peak value), narrow-angle (field of view = 0 29), high ...spatial resolution (pixel scale = 1 02) visible light imager used on NASA's New Horizons (NH) mission for both science observations and optical navigation. Calibration observations began several months after the New Horizons launch on 2006 January 19 and have been repeated approximately annually throughout the course of the mission, which is ongoing. This paper describes the in-flight LORRI calibration measurements, and the results derived from our analysis of the calibration data. LORRI has been remarkably stable over time with no detectable changes (at the ∼1% level) in sensitivity or optical performance since launch. The point-spread function varies over the FOV but is well-characterized and stable, enabling accurate deconvolution to recover the highest possible spatial resolution during observations of resolved targets, especially when multiple, overlapping images are obtained. By employing 4 × 4 re-binning of the CCD pixels during read out, a special spacecraft tracking mode, exposure times of ∼30 s, and co-addition of ∼100 images, LORRI can detect unresolved targets down to V 22 with a signal-to-noise ratio (S/N) of ∼5. LORRI images have an instantaneous dynamic range of ∼3500, which combined with exposure time control ranging from 0 ms to 64,967 ms in 1 ms steps supports high resolution, high sensitivity imaging of planetary targets spanning heliocentric distances from Jupiter to deep in the Kuiper Belt, enabling a wide variety of scientific investigations. We describe here how to transform LORRI images from raw (engineering) units into scientific (calibrated) units for both resolved and unresolved targets. Assuming that the wavelength variation of LORRI's sensitivity is accurately described by the ground-based calibration, we estimate that LORRI's absolute sensitivity is accurate to ∼2% (1 ) for targets with solar-type spectral energy distributions (SEDs). The accuracy of the absolute calibration for targets with other SEDs should be comparably good when employing synthetic photometry techniques, which we do when deriving LORRI's photometry keywords. We also describe various instrumental artifacts that could affect the interpretation of LORRI images under some observing circumstances.
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