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Methane, as the second most emitted greenhouse gas (GHG), has a warming potential of approximately 86 times that of carbon dioxide within 20 years. Quantifying methane emissions is helpful to the country's emission reduction efforts. However, currently, there is a lack of measurement data of methane emissions from natural gas fueling stations in China. In this study, a downwind quantification approach was employed to directly measure the methane emissions of nine compressed natural gas (CNG) fueling stations in East China according to the Environmental Protection Agency's Other Test Method 33A (OTM 33A). Moreover, methane concentrations were also measured near the nozzle of the refueling dispenser and the process equipment in the station. The methane emissions of the nine stations lied within the range of 0.11-0.83 kg/h, and the distribution of the emission rate was skewed. It was found that the emissions from gas fueling stations could be divided into intermittent emissions and continuous emissions, of which the intermittent emissions were the main source of methane.

Abstract The practical applications of zinc metal batteries are plagued by the dendritic propagation of its metal anodes due to the limited transfer rate of charge and mass at the electrode/electrolyte interphase. To enhance the reversibility of Zn metal, a quasi-solid interphase composed by defective metal–organic framework (MOF) nanoparticles (D-UiO-66) and two kinds of zinc salts electrolytes is fabricated on the Zn surface served as a zinc ions reservoir. Particularly, anions in the aqueous electrolytes could be spontaneously anchored onto the Lewis acidic sites in defective MOF channels. With the synergistic effect between the MOF channels and the anchored anions, Zn2+ transport is prompted significantly. Simultaneously, such quasi-solid interphase boost charge and mass transfer of Zn2+, leading to a high zinc transference number, good ionic conductivity, and high Zn2+ concentration near the anode, which mitigates Zn dendrite growth obviously. Encouragingly, unprecedented average coulombic efficiency of 99.8% is achieved in the Zn||Cu cell with the proposed quasi-solid interphase. The cycling performance of D-UiO-66@Zn||MnO2 (~ 92.9% capacity retention after 2000 cycles) and D-UiO-66@Zn||NH4V4O10 (~ 84.0% capacity retention after 800 cycles) prove the feasibility of the quasi-solid interphase.

Under the background of urgent need for computer-aided technology to provide physicians with objective decision support, aiming at reducing the false positive rate of nodule CT detection in pulmonary nodules detection and improving the accuracy of lung nodule recognition, this paper puts forward a method based on ensemble learning to distinguish between malignant and benign pulmonary nodules. Firstly, trained on a public data set, a multi-layer feature fusion YOLOv3 network is used to detect lung nodules. Secondly, a CNN was trained to differentiate benign from malignant pulmonary nodules. Then, based on the idea of ensemble learning, the confidence probability of the above two models and the label of the training set are taken as data features to build a Logistic regression model. Finally, two test sets (public data set and private data set) were tested, and the confidence probability output by the two models was fused into the established logistic regression model to determine benign and malignant pulmonary nodules. The YOLOv3 network was trained to detect chest CT images of the test set. The number of pulmonary nodules detected in the public and private test sets was 356 and 314, respectively. The accuracy, sensitivity and specificity of the two test sets were 80.97%, 81.63%, 78.75% and 79.69%, 86.59%, 72.16%, respectively. With CNN training pulmonary nodules benign and malignant discriminant model analysis of two kinds of test set, the result of accuracy, sensitivity and specificity were 90.12%, 90.66%, 89.47% and 88.57%, 85.62%, 90.87%, respectively. Fused model based on YOLOv3 network and CNN is tested on two test sets, and the result of accuracy, sensitivity and specificity were 93.82%, 94.85%, 92.59% and 92.31%, 92.68%, 91.89%, respectively. The ensemble learning model is more effective than YOLOv3 network and CNN in removing false positives, and the accuracy of the ensemble. Learning model is higher than the other two networks in identifying pulmonary nodules.

In this paper a systemic approach that combines Failure Mode and Effect Analysis (FMEA) and trapezoidal intuitionistic fuzzy information axiomatic design (TIFIAD) is proposed to identify the risk of railway dangerous goods transportation system (RDNGTS), which has seven steps: (1) identify potential risk factors and risk sub-indicators of RDNGTS; (2) define the failure criterion of severity of failures (S), portability of occurrence (O) and possibility of detection (D) of FMEA based on trapezoidal intuitionistic fuzzy numbers (TrIFNs); (3) invite experts to score the TrIFNs of S, O and D for each risk sub-indicator; (4) aggregate the TrIFNs of S, O and D for each risk sub-indicator; (5) calculate the TIFIAD of each risk sub-indicator; (6) calculate the total TIFIAD of each risk sub-indicator; (7) calculate the total TIFIAD of each risk factor. Compared with FMEA, FMEA–TIFIAD has the following improvements: (1) The TrIFNs are applied to score the S, O and D of each risk sub-indicator of RDNGTS; (2) The TIFIAD of the S, O and D are calculated for each risk sub-indicator, the product of the S, O and D could replace the Risk Priority Number (RPN) of FMEA; (3) The Entropy Weight Method is used to calculate the weight of each risk sub-indicator. The calculation results show that the potential human risk should be paid more attentions; the FMEA–TIFIAD is more reliable and accurate than FMEA. Finally the improvement suggestions for managers and operators of RDNGTS are given.

The high-temperature oxidation of ZrAl2 upon exposure to pure O2 at 800–950 °C was studied in terms of the oxidation kinetics and the formation mechanism of the oxide layer. The alloy followed parabolic oxidation kinetics, and the activation energy of oxidation was 239 ± 14 kJ/mol. During the early stages of oxidation below 850 °C, a single-layer oxide formed due to the crystallization of the initially formed amorphous oxide layer. A multilayer oxide structure developed at higher temperatures, due to the slightly higher affinity of oxygen for Zr than for Al and the oxidation-induced compositional changes.

This study aimed to evaluate the usefulness of [99mTc]sestamibi ([99mTc]MIBI) single photon emission computed tomography (SPECT)/X-ray computed tomography (CT) imaging for the identification of dystonic muscles in primary cervical dystonia (PCD) patients who underwent botulinum neurotoxin type A (BoNT-A) therapy. Thirty-six patients with PCD and 10 healthy subjects (control group) who underwent [99mTc]MIBI SPECT/CT were enrolled. The image characteristics of dystonic muscles and normal muscles were evaluated. Muscle/background ratio (MBR) of six representative muscles was calculated for dystonic muscles in PCD group and normal muscles in control group. In PCD patients, target muscles injected with BoNT-A were selected by clinical evaluations and the results of needle electromyography (EMG) were considered as the gold standard. The sensitivity, specificity, and diagnostic efficacy of SPECT/CT were obtained from the receiver operator characteristic (ROC) curve. Twenty-four PCD patients were included in our study eventually, because three PCD patients whose follow-up were lost and 9 PCD patients whose maximum reduction of Tsui scale scores was

Background Suo Quan Wan (SQW) is an effective traditional Chinese prescription on treated lower urinary tract symptoms (LUTS), and has been proved have modulation effect on the expression of transient receptor potential vanilloid 1 (TRPV1) in accordance with the recovery of bladder function of overactive bladder rat. This study further investigated the mechanism of SQW modulated TRPV1 signaling and bladder function using TRPV1 knockout (KO) mice. Methods Study was conducted using wild type and TRPV1 KO mice. The KO animals were grouped into KO group and SQW treated group. We applied in vivo cystometrogram recording techniques to analyze voiding control of the urinary bladder, as well as in vitro organ bath to study bladder distension response to various compounds, which subsequently elicited normal smooth muscle excitation. Real-time polymerase chain reaction and western blot analysis were performed to quantify the expression of TRPV1 and P2X3 in the bladder. ATP released from bladder strips was measured using the luciferin–luciferase ATP bioluminescence assay kit. Results KO preparation inhibited decrease micturition times, while micturition interval and volume were increased. Results of urodynamic record of the TRPV1−/− mice during NS infusion showed reduced bladder pressure and contraction which exhibited decreased response to α, β-me ATP, KCl, and carbachol and no response to CAP. The ATP released by the TRPV1−/− mice from strips of bladder smooth muscles was significantly reduced, along with no TRPV1 expression and reduced expression level of P2X3 in the bladder. SQW could increase ATP release in some degree, while had no effect on TRPV1 and P2X3 expression. SQW could improve bladder pressure slightly, while make no significantly effects on the force response to α,β-meATP, CAP, carbachol in gradient concentration, and KCl, as well as MBC and voiding activities. Conclusions TRPV1 plays an important role in urinary bladder mechanosensitivity. The effective SQW is hard to play its proper role on bladder function of mice without TRPV1. Electronic supplementary material The online version of this article (doi:10.1186/s12906-016-1420-6) contains supplementary material, which is available to authorized users.

Subtype H7 avian–origin influenza A viruses (AIVs) have caused at least 500 confirmed human infections since 2003 and culling of >75 million birds in recent years. Here we antigenically and genetically characterized 93 AIV isolates from North America (85 from migratory waterfowl [1976–2010], 7 from domestic poultry [1971–2012], and 1 from a seal [1980]). The hemagglutinin gene of these H7 viruses are separated from those from Eurasia. Gradual accumulation of nucleotide and amino acid substitutions was observed in the hemagglutinin of H7 AIVs from waterfowl and domestic poultry. Genotype characterization suggested that H7 AIVs in wild birds form diverse and transient internal gene constellations. Serologic analyses showed that the 93 isolates cross-reacted with each other to different extents. Antigenic cartography showed that the average antigenic distance among them was 1.14 units (standard deviation [SD], 0.57 unit) and that antigenic diversity among the H7 isolates we tested was limited. Our results suggest that the continuous genetic evolution has not led to significant antigenic diversity for H7 AIVs from North America. These findings add to our understanding of the natural history of IAVs and will inform public health decision-making regarding the threat these viruses pose to humans and poultry.

The surface tension of carbonated monoethanolamine aqueous solutions from 293.15 to 323.15 K was measured by using an automatic surface tension-meter. A model applicable for the surface tension of MEA-CO2-water mixtures was proposed and the calculated results agreed well with the experiments. The influences of temperature, MEA concentration and CO2 loading were demonstrated on the basis of experiments and calculations.

As physical and chemical tests alone are not sufficient enough for the assessment of potential effects on aquatic organisms, bioassays are required for the integrated evaluation of water pollution. In this study, invertebrate crustacean Artemia salina (brine shrimp) was applied as an indicator to assess the water quality of Hangzhou Section of Beijing-Hangzhou Grand Canal. The percentage mortality of brine shrimp was recorded after 24-h exposure to the Canal water. The water samples were collected from five typical sites during October 2008 and April 2009. It exhibited 11% ± 8.3%, 26.7% ± 17%, 31.7% ± 8.5%, 28.0% ± 11.7%, and 4% ± 4.3% percentage mortality for the sample from Tangxi Bridge, Yi Bridge, Gongchen Bridge, Maiyu Bridge, and Gujia Bridge in 2008, respectively. And it exhibited 5.7% ± 4.2%, 10.3% ± 8.2%, 24.3% ± 12.3%, 16.0% ± 12.3%, and 0%, percentage mortality in 2009, respectively. According to the results, a relative improvement in water quality was observed, although the results were not significantly different at the p < 0.05 level. It suggested that 24-h A. salina exposure trials represent an acceptable bioassay for water toxicity when alternative bioassays were unavailable.