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The Multiband Ultraviolet Spectrum Imager (MUSI) is an optical remote sensing instrument scheduled to launch on the Fengyun‐4C meteorological satellite in 2024. MUSI is designed to measure the airglow emissions between ∼120 and 160 nm above the East Asia and Pacific region from a geostationary orbit to infer ionospheric parameters. Here we develop a lookup‐table algorithm for retrieving the peak electron density (nmF2) and the Total Electron Content (TEC) from nighttime observations of the OI 135.6 nm emission. The algorithm takes into account the north‐south asymmetry of the equatorial ionization anomaly and the atmospheric variations with solar activity and local time. Analysis of synthetic observations shows that the assumptions made in the algorithm only lead to ∼2%–4% uncertainties in the retrievals under the modeled ionospheric conditions. The algorithm is verified by retrieving nmF2 and TEC from the Global‐Scale Observations of the Limb and Disk (GOLD) mission and comparing with coincided radio measurements. The comparison indicates almost negligible systematic differences (typically less than ∼3%) between the GOLD and the ionosonde nmF2, which are within the error limit of the GOLD retrievals. The accuracy of the GOLD TEC retrievals is shown to be comparable to (or in some sense even better than) that of the measurements from the Global Navigation Satellite System. Several simplified yet robust retrieval methods are also developed, which can be readily implemented for both existing and upcoming missions. Our results promote far ultraviolet (FUV) remote sensing to be a key technology for accurate determination of the ionospheric state. Key Points: We develop a lookup‐table algorithm for ionosphere retrieval with the FUV spectral imager on the Fengyun‐4C geostationary satelliteAssumptions made in the algorithm lead to only ∼2%–4% uncertainties in the nmF2 and Total Electron Content (TEC) retrievals under the modeled ionospheric conditionsThe algorithm is verified by retrieving nmF2 and TEC from the Global‐Scale Observations of the Limb and Disk observations and comparing with external radio measurements [ABSTRACT FROM AUTHOR]

Diamond based quantum sensing for on‐chip electromagnetic field imaging is an emerging field. While smaller diamond probes offer higher spatial resolution, their lower fluorescence intensity poses a challenge for the traditional Avalanche Photo Diode. In this work, we propose a tapered fiber diamond probe containing Nitrogen‐vacancy center and utilize a single photon counter module as the detector. A time domain differential pulse sequence is introduced to suppress noise caused by laser intensity fluctuation. By analyzing the relationship between the signal‐to‐noise ratio (SNR) and parameters of differential pulse sequence, we derived the formula of SNR and the basic cycle (M $M$), and obtained the optimal SNR in the same measurement time through trade‐off between two different kinds of noise. The technique was applied to a waveguide microstrip filter chip, accurately imaging the current density distribution. Our results have potential applications in on‐chip testing and failure analysis. [ABSTRACT FROM AUTHOR]

With the increasing integration and complexity of chips, the problem of wafer‐level electromagnetic compatibility (EMC) is becoming more and more prominent, and the spatial resolution and operating frequency of existing EMC test techniques can no longer meet the demand for wafer‐level EMC testing. In this work, a surface H‐field imaging system based on a micron‐sized diamond crystal containing nitrogen‐vacancy centers is proposed, which is micrometer resolved, quantum calibrated, frequency tunable, and nonintrusive to the H‐field of the device to be tested. The surface H‐field of a limiter chip at different input power is scanned for imaging, revealing how the energy is dissipated across the chip when exceeding limiting power. The result is essential for understanding the workings of the limiter chip and for optimizing the chip design. [ABSTRACT FROM AUTHOR]

Objective: We aimed to compare perinatal outcomes between umbilical cord occlusion techniques in monochorionic pregnancies, including umbilical cord ligation, fetoscopic laser coagulation, interstitial laser coagulation, bipolar cord occlusion, radiofrequency ablation, and microwave ablation. Methods: This study was registered with PROSPERO (CRD42020158861). PubMed, Web of Science, Cochrane Library, and Embase were searched for studies published up to May 2020. The DerSimonian‐Laird random‐effects model was used for the meta‐analysis. Subgroup analyses were performed to compare the outcomes among the six techniques. Meta‐regression was used to adjust for confounders. Results: Thirty‐four studies with 1646 participants were included. The overall survival was 76.5% after umbilical cord ligation, 78.8% after fetoscopic laser coagulation, 60.3% after interstitial laser coagulation, 79.2% after bipolar cord occlusion, 77.5% after radiofrequency ablation, and 75.0% after microwave ablation. Subgroup comparison showed the rates of overall survival and preterm premature rupture of membranes were not significant different among six techniques. However, rates of fetal loss, premature birth, live birth, and neonatal death differed significantly among the six groups. Conclusions: The choice of umbilical cord occlusion techniques will affect perinatal outcomes. We suggested that the choice of umbilical cord occlusion techniques should fully consider these differences among techniques. Key points: What's already known about this topic? Several techniques have been used for selective feticide of monochorionic pregnancies.Bipolar cord occlusion and radiofrequency ablation are two commonly used minimally invasive methods for selective feticide.However, whether the pregnancy outcomes are different among different techniques is still unknown. What does this study add? This is the first meta‐analysis comparing perinatal outcomes among six techniques of selective feticide in monochorionic pregnancies.Our findings showed that the overall survival rate after umbilical cord occlusion was 77.1% (95% CI: 73.9%–80.2%).Besides, fetal loss, premature birth, live birth, and neonatal death rates differed significantly among the six techniques.Our study suggested that the choice of umbilical cord occlusion should fully consider the difference in perinatal outcomes among procedures. [ABSTRACT FROM AUTHOR]

The Chinese government has established a three‐tier maternal care system covering the entire country and providing integrated antenatal care (ANC) for pregnancies. This study aimed to analyze the direct and indirect effects of ANC services on early childhood development. A community‐based cross‐sectional survey was conducted for mothers' ANC visits and assessments of early childhood development in Shanxi and Guizhou provinces, China. A total of 1660 mother–child dyads were included in current analyses: 29.2% of mothers did not receive any ANC (ANC1), 23.3% of mothers received ANC three or fewer times (ANC2), and 47.5% of mothers received ANC four or more times (ANC3). Children whose mothers received ANC services had a significantly lower risk of overall developmental delay (OR = 0.60, 95% CI: 0.44–0.81 for ANC2; and OR = 0.44, 95% CI: 0.34–0.59 for ANC3) and social‐emotional developmental delay (OR = 0.68, 95% CI: 0.49–0.94 for ANC3). Furthermore, a significant pathway relationship mediated by maternal depression and nurturing care was found between ANC and developmental delay. This study showed ANC services significantly reduced the risk of developmental delay in offspring. We also suggest that a nationwide ANC system can be a good delivery platform for scaled‐up early childhood development interventions. [ABSTRACT FROM AUTHOR]

ABSTRACT Transcriptome analysis is important for interpreting the functional elements of the genome and revealing the molecular constituents of cells and tissues. Herein, differentially transcribed genes were identified by deep sequencing after zebrafish ( Danio rerio) were exposed to β-diketone antibiotics (DKAs); 23,129 and 23,550 mapped genes were detected in control and treatment groups, a total of 3238 genes were differentially expressed between control and treatment groups. Of these genes, 328 genes (213 up- and 115 down-regulation) had significant differential expression ( p < 0.05) and an expression ratio (control/treatment) of >2 or <0.5. Additionally, we performed Gene Ontology (GO) category and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, and found 266 genes in the treatment group with annotation terms linked to the GO category. A total of 77 differentially expressed transcriptional genes were associated with 132 predicted KEGG metabolic pathways. Serious liver tissue damage was reflected and consistent with the differences in genetic classification and function from the transcriptome analysis. These results enhance our understanding of zebrafish developmental processes under exposure to DKA stress. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1357-1371, 2016. [ABSTRACT FROM AUTHOR]

ABSTRACT Fluoroquinolones (FQs) and tetracyclines (TCs), the two β-diketone antibiotics (DKAs), are two frequently detected pollutants in the environment; however, little data are available on their combined toxicity to zebrafish ( Danio rerio). This study reports that toxicologic effects of combined DKA (FQs-TCs) exposure on zebrafish were comparable with or slightly less than those of TCs alone, showing that TCs played a major toxicologic role in the mixtures. The effects of FQs, TCs, and DKAs on malformation rates of zebrafish were dose dependent, with EC50 values of 481.3, 16.4, and 135.1 mg/L, respectively. According to the combined effects of DKAs on zebrafish hatching, mortality, and malformation rates, the interaction between FQs and TCs was shown to be antagonistic based on three assessment methods: Toxic Unit, Additional Index, and Mixture Toxic Index. The 1.56 mg/L TC and 9.38 mg/L DKA treatments resulted in higher zebrafish basal swimming rate compared with the control group at 120 hours postfertilization (hpf). in both light and light-to-dark photoperiod experiments. Under conditions of no obvious abnormality in cardiac development, the heart beats were decreased significantly because of DKA exposure, such as decreasing by ∼20% at 150 mg/L DKAs. Transmission electron microscopy observation of myocytes from DKA-exposed hearts displayed prominent interruptions and myofibrillar disorganization of the normal parallel alignment of thick and thin filaments, and partial edematous and dissolved membranes of cell nuclear tissues. At 90 mg/L DKAs, the transcriptional levels of the acta1a, myl7, and gle1b genes, related to heart development and skeletal muscle formation, were significantly changed. This is consistent with the swimming behavior and histopathologic results obtained by transmission electron microscopy. In summary, the toxicity of the combined DKAs to zebrafish was comparable with or less than that of TCs alone and had the ability to impair individual behaviors that are of great importance in the assessment of their ecologic fitness. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 736-750, 2016. [ABSTRACT FROM AUTHOR]

The removal efficiency of Cu2+ by Spirulina platensis (strain FACHB-834), in viable and heat-inactivated forms, was investigated in the presence and absence of linear alkylbenzene sulfonate ( LAS). When the initial Cu2+ concentration was in the range of 0.5-1.5 mg · L−1, a slight increase in growth rate of FACHB-834 was observed. In contrast, when Cu2+ or LAS concentrations were at or higher than 2.0 or 6.0 mg · L−1, respectively, the growth of FACHB-834 was inhibited and displayed yellowing and fragmentation of filaments. The presence of LAS improved Cu2+ removal by ~20%, and accelerated attainment of Cu2+ retention equilibrium. For the 2- mg · L−1 Cu2+ treatments, retention equilibrium occurred within 2 d and showed maximum Cu2+ removal of 1.83 mg · L−1. In the presence of LAS, the ratio of extracellular bound Cu2+ to intracellular Cu2+ taken up by the cells was lower (1.05-2.26) than corresponding ratios (2.46-7.85) in the absence of LAS. The percentages of extracellular bound Cu2+ to total Cu2+ removal (both bound and taken up by cells) in the presence of LAS ranged from 51.2% to 69.3%, which was lower than their corresponding percentages (71.1%-88.7%) in the absence of LAS. LAS promoted biologically active transport of the extracellular bound form of Cu2+ into the cell. In contrast, the addition of LAS did not increase the maximum removal efficiency of Cu2+ (61.4% ± 5.6%) by heat-inactivated cells compared to that of living cells (59.6% ± 6.0%). These results provide a theoretical foundation for designing bioremediation strategies using FACHB-834 for use in surface waters contaminated by both heavy metals and LAS. [ABSTRACT FROM AUTHOR]