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Tetrahymena piriformis belongs to the ciliated protists (ciliates), causing severe economic losses in aquaculture. Chemical drugs currently used usually have toxic side effects, and there is no specific drug against Tetrahymena. Therefore, it is an urgent need to identify new antiparasitic lead compounds. In the present study, the in vitro parasiticidal activity of ethyl acetate (EtOAc) extracts and water extracts from 22 selected traditional Chinese medicines (TCMs) were evaluated against T. piriformis. The EtOAc extract of P. corylifolia turned out to be the most active with the minimum parasiticidal concentration of 100 mg/L within 3 h. Thus, it was separated into 12 fractions by the first-dimensional (D1) normal phase liquid chromatography (NPLC), meanwhile combining with in vitro antiparasitic tests for activity tracking. Subsequently, 8 flavonoids were identified in the active fractions by the second-dimensional (D2) reverse phase liquid chromatography (RPLC) tandem high-resolution mass spectrometry. According to the results, 5 flavonoids were selected for in vitro antiparasitic test, of which isobavachalcone showed the minimum parasiticidal concentration of 3.125 mg/L in 2 h. Bathing treatment of infected guppies with isobavachalcone could significantly reduce the burden of T. piriformis , obtaining a 24-h median effective concentration (24-h EC 50) value of 1.916 mg/L. And the concentration of isobavachalcone causing guppies to die within 24 h is 39 times than that of 24-h EC 50. The results demonstrated that isobavachalcone has the potential to be developed into a novel commercial fish drug against T. piriformis. [Display omitted] • The EtOAc extract of Psoralea corylifolia has activity against Tetrahymena piriformis. • Bavachinin A, Bavachin D, Corylifol A, Neobavaisoflavone and Isobavachalcone were identified. • The acute toxicity and anthelmintic effect of isobavachalcone on Poecilia reticulate were studied. [ABSTRACT FROM AUTHOR]

This work considers connected testbeds, i.e., engineering testbeds that are remotely accessible over a network, and focuses on the challenge of achieving a high-fidelity closed-loop integration despite the network delays. To address this challenge, a model-free framework is presented. In previous work, a model-free delay compensation framework with a single design parameter was developed. However, having only one design parameter could limit tuning flexibility and thus delay compensation performance. Furthermore, this framework has not yet been validated on an actual connected testbed. To address these two shortcomings, in this article, this delay compensation framework is first expanded into a two-parameter form, and its open-loop stability and performance are studied for constant delays. The predictor stability criterion is established in terms of the two design parameters and the constant network delay. To evaluate the transient delay compensation performance of this framework and understand its advantages and limitations, simulation case studies are conducted on a connected engine testbed representing a medium-duty diesel pickup truck. These studies include two testbed architectures, constant and variable delays, two drive cycles, two levels of driver aggressiveness, and a comparison against wave transformation as a state-of-the-art benchmark. Finally, the framework is tested experimentally on a physical realization of the same connected testbed. The results validate the robustness of the delay compensation performance of the framework under dynamic operations, and show up to 30% higher integration fidelity due to the additional design degree of freedom introduced through the two-parameter form. [ABSTRACT FROM AUTHOR]

High temperature gas turbine sealing is an important issue for increasing the thermal efficiency of gas turbine. In this purpose, layered structured LaPO has been selected as the soft phase to add into the commercialized thermal barrier coating material 7 wt% yttria stabilized zirconia (7YSZ). The consequent thermal conductivities and mechanical properties versus the content of LaPO have been researched systemically in this paper. Phase composition and microstructure of the high-temperature sintered LaPO/7YSZ composites were characterized. The thermal conductivity decreases significantly due to the second phase effects and the interface thermal resistance was also strongly involved according to the composite model. The hardness decreased by composed LaPO phase so that to reduce attrition of the vanes at high temperature. The slight increase of fracture toughness and bending strength in the results were also favored in operation. The experimental results demonstrate that the LaPO/7YSZ composite will be an excellent candidate abradable sealing material for high temperature gas turbine. [ABSTRACT FROM AUTHOR]

The CaO‐MgO‐Al2O3‐SiO2 (CMAS) corrosion of thermal barrier coatings (TBCs) is a crucial problem for the lifetime of blades and vanes of jet engine and gas turbine at high operating temperature. Although many new alternative materials for TBCs have been developed in recent years, their application is limited by the CMAS corrosion. On the other hand, the composition difference of CMAS between regions makes solving this problem very difficult. Therefore, in this study, the yearly composition changes of sand‐dust around Beijing area were investigated. The high‐temperature corrosion behavior of air‐plasma‐sprayed 8YSZ and newly developed (LaxYb1−x)2Zr2O7 TBCs by the representative sand‐dust of Beijing was investigated. In comparison, a universally used CaO‐riched composition of simulated silicate deposit was also adopted for the TBCs corrosion test. It is found that the (LaxYb1−x)2Zr2O7 TBCs performs much better anti‐corrosion behavior than that of 8YSZ, both by Beijing sand‐dust and simulated one. Particularly, Yb2Zr2O7 TBCs appear to be the optimum material against silicate deposits attack. The mechanism of silicate deposits corrosion has also been discussed. [ABSTRACT FROM AUTHOR]

A severe disease occurred in farmed Eriocheir sinensis characterized by milky liquid accumulation in the pectoral cavity, in the province of Liaoning, China, during October 2018–April 2019. Diseased crabs moved sluggishly, exhibited appetite loss and readily lost legs. Under the microscopic analysis, it was observed that the milky liquid contained a large number of yeastlike microorganisms (0.8–1.2 μm × 1.5–1.9 μm), which were also present in the muscle, hepatopancreas and gills. A dominant strain was isolated from the milky liquid and other tissues of diseased crabs. It grew on nutrient agar and formed 1‐ to 3‐mm white opaque colonies, each with a protuberance in the centre. Besides, the results of TEM and SEM also demonstrate a typical multilateral budding model of the yeast clearly. We identified the strain, which we named 2EJM001, as Metschnikowia bicuspidata based on 18S rDNA, ITS and 26S rDNA sequence analyses and on its morphological, physiological and biochemical characteristics. Phylogenetic analysis revealed that 26S rDNA of 2EJM001 was clustered with M. bicuspidata (LNES0119) as reported by Bao et al. In addition, unlike Bao et al., two challenge experiments (injection and immersion) were used in this study. The results of challenge experiments show that 2EJM001 was pathogenic to E. sinensis and caused signs similar to those found in the naturally infected crabs. At the same time, the minimum inhibitory concentrations (MIC80 and MIC90) were determined. This study further confirms that M. bicuspidata 2EJM001 was the pathogen responsible for 'milky disease' in E. sinensis from Liaoning Province. [ABSTRACT FROM AUTHOR]

Coal-dominated winter heating practices in China are largely accepted to be a leading cause of winter haze in the region though the amount of coal for heating is actually much lower than for power generation or industrial process. However, little is known about how the total rural coal weight in a region could be attributed to real time (e.g., daily) patterns, limiting the understanding of dynamic impacts of coal emissions and the adoption of timely measures against predicted haze. Considering that winter heating essentially protects against cold temperatures, coal burning strength may be related to the temperatures that people experience. A field study was organized to test the validity of this hypothesis. A system was designed to continuously monitor every instance of coal addition, and coal consumption on any given day for a whole village (W DAY) was calculated by summating all the additions. Meanwhile, a new term, composite temperature (T COM), which incorporates a few weather-related elements, was introduced to represent cold temperatures that individuals experience. It was found that W DAY and T COM presented opposite variations, and a negative linear correlation was observed (W DAY = −0.75 T COM + 11.86, R 2 = 0.75), revealing the feasibility of estimating coal consumption on a certain day (W DAY) based on weather data (T COM) for a given village. An extensive form of the algorithm for any area of interest (e.g., a district, city, or province) can be expressed as W DAY = (−0.75 T COM + 11.86)‧ N H /834, where N H denotes the number of households in a region. This algorithm reflects the essence of winter heating (to resist cold temperatures), and therefore its logic is highly likely to be useful for any countries of the world regardless of what forms of energy used (coal or other energy forms) provided the energy involved is unexceptionally used for winter heating, though there may be some uncertainties in estimated coal consumption due to multiple factors. Unlabelled Image • Coal consumption and weather condition simultaneously monitored in a heating season • An algorithm for calculating daily coal consumption (emission) based on temperature • The algorithm enables real time simulation of heating coal impact on air quality. • The inside logic may find application in any countries with winter heating practice. [ABSTRACT FROM AUTHOR]

Highlights • A new definition of "safety" is given from the view of the interaction between activities and environment. • The safety structure consisting of the atomic activity factor, atomic environment factor and the interaction between the two is developed. • The new definition of hazard based on the safety structure and its active identification method is proposed. • The guiding ideology for establishing dynamic risk measurement and prediction models of safety events is given. • The three-stage echelon active safety control mechanism for safety events is established. Abstract In order to reveal the essence of "safety", to realize the active identification of hazard and the active prevention and control of accidents, the safety structure theory (SST) is established in this paper. A new definition of "safety" is given from the view of the interaction between activities and environment. And the definition of the instability domain of safety events is given based on the definition of connotation in logic. According to the factor space theory (FST), factors are used to express activities and environment, then the environment factors space cane (EFSC) is developed to "bearing" the states of environment and safety events, and the atomic activity factor space (AAFS) is developed to "bearing" the states of activities. The mapping from EFSC × AAFS to EFSC is established to describe the interaction between the atomic activity factor (AAF) and atomic environment factor (AEF), then the safety structure consisting of AAF, AEF, and the interaction between the two is developed. The evolution mechanism and evolution process of safety issues are analyzed according to the changes of states of safety structures and the relationships between the states of simple environment factors (SEFs) and instability domain of safety events. Then the definition of hazard based on safety structures and the active identification method are given, and the guiding ideology for establishing dynamic risk measurement and prediction models of safety events is given. According to the risk assessment and prediction, a three-stage echelon active safety control mechanism for safety events consisting of advanced feedforward control, feedforward control and feedback control is established. SST is a new safety science theory, which can provide a new analysis method for revealing the essence of "safety" and the evolution mechanism of safety issues, and open up a new way for the development of active safety control. [ABSTRACT FROM AUTHOR]

Aims Ranolazine, an antianginal agent used for chronic stable angina treatment, was demonstrated to be effective in atrial fibrillation (AF) treatment. The aim of this study was to explore the molecular mechanisms of its anti-AF effects. Main methods AF rat model was established using acetylcholine (ACh)-CaCl 2 injection for 7 days followed by ACh infusion into the heart. Prior to ACh infusion, ranolazine at 10.7 mg/kg/0.5 ml was injected into vein and followed by 0.56 mg/kg/min infusion. Blood pressure and electrocardiogram were monitored during the infusion. Histological changes of atrial tissue were observed after H&E staining. Activities and protein expression of NADPH oxidase-4, xanthine oxidase, glutathione peroxidase and superoxide dismutase were examined using commercial assay kits and Western botting, respectively. Mitochondrial functions were evaluated through membrane potential, ATP production, activities of complex I and III and reactive oxygen species production. Apoptosis was measured using TUNEL staining. Protein expression of apoptotic proteins Bcl-2, Bax and cleaved-caspase 3 and Akt/mTOR signaling proteins were detected using Western blotting. Key findings Results demonstrated that ranolazine attenuated AF in ACh-CaCl 2 -exposed rats. In addition, ranolazine restored mitochondrial function, suppressed oxidative stress, and inhibited atrial cells apoptosis. Furthermore, the activated Akt/mTOR signaling pathway induced by AF was further activated by ranolazine. Significance The present study confirms the effects of ranolazine on AF rats induced by ACh-CaCl 2 , and provides evidence that the anti-AF effects are associated with the restoration of mitochondrial function and activation of the Akt/mTOR signaling pathway in atrial tissue. [ABSTRACT FROM AUTHOR]

As brown carbon (BrC) consists of a collection of light-absorbing organic compounds, there is unlikely an individual substance that can be used as a proxy of all BrC constituents. Hence, available methods for distinguishing BrC from black carbon (BC) are often flawed. Moreover, the use of household solid fuels for winter rural heating is a common practice in northern China that significantly contributes to air pollution; however, it is unclear whether the intensive consumption of solid fuels during the heating season influences the yearly BrC emissions and the seasonal features of ambient BrC in northern China, which is a concern for future BrC control. Thus, a reliable method is necessary for determining the concentrations and optical properties of ambient BrC in different seasons. In this study, four typical months were selected to represent the four seasons of the year in Beijing. Daily atmospheric samples were collected using quartz filters for the analysis of BrC and BC. The integrating sphere (IS) approach was used for the first time to separate the light absorption of BrC from that of BC in ambient PM 2.5. We found that the yearly average abundance of BrC was 0.82 ± 0.44 μg m−3, peaking at 2.31 ± 0.44 μg m−3 in winter, followed by autumn, spring, and summer. Meanwhile, the solar energy absorption by BrC relative to that by BrC + BC across 350–850 nm (F BrC) was the highest in winter (21.78 ± 3.56%), followed by autumn (11.53 ± 5.29%), spring (6.38 ± 4.06%), and summer (4.26 ± 2.57%). The seasonal variations in BrC abundance and absorption share were consistent with the use of household heating practices (highest in winter and minor uses in late autumn and early spring), with biomass and/or coal being the dominant energy types. As low-efficiency burning of solid biomass fuels and fossil fuels is considered an important source of BrC, the aforementioned correlation suggests that rural residential heating plays a dominant role in controlling the seasonal features of BrC and should therefore be a main focus for BrC control in northern China. Hence, the ongoing pursuit of clean heating (switching from coal to gas or electricity) in northern China will help to mitigate the climate-warming effects of both BrC and BC and offset some of the adverse impacts of clean air efforts on climate. Our findings also have wider implications for pollution mitigation in other global regions that use solid fuels. • Brown and black carbon of Beijing PM 2.5 samples optically separated by integrating sphere method. • The seasonality of BrC parameters suggests taking household solid fuels as control focus. • The results also senseful even in other regions of the world using solid fuels. [ABSTRACT FROM AUTHOR]

Catering oil fumes are a major hazard to human health. In particular, the typical Chinese cooking style is characterised by a high temperature frying process that produces high levels of cooking oil fumes. However, limited data relating to this sector mean that national emission inventory data specific to the catering service industry do not exist. To address above deficiency and thus to establish the inventory of a city, or a province, or even a country, a door-to-door survey campaign was launched in the Chinese cities of Heze and Linfen to determine the structure of local catering industries. Data revealed that the number of catering businesses per 104 people was 17 ± 4. Of these, 3.0 ± 1.4, 15.0 ± 1.4, and 82.0 ± 0.0% were classified as large, medium, and small enterprises, respectively. Furthermore, the installation rates of fume purifiers were 74 ± 13, 66 ± 9, and 51 ± 14% for large, medium, and small enterprises, respectively, with net removal efficiencies of 63 ± 11, 50 ± 7, and 31 ± 8%, respectively. This information was extrapolated across all provincial regions of China to construct a provincial and national emission inventory. In 2017, China's national catering industry released approximately 34 kt of volatile organic compounds (VOCs), 38 kt of particulate matter with a diameter less than 2.5 μm (PM 2.5), 48 kt of particulate matter with a diameter less than 10 μm (PM 10), 1 kt of black carbon (BC), and 27 kt of organic carbon (OC). A significant correlation was observed between vegetable oil consumption and emissions (e.g., for VOCs, y = 14.94 x + 76.50, R2 = 0.87, where y is VOCs emissions and x is vegetable oil consumption), indirectly corroborating the rationality of the inventory. Moreover, this correlation provides the potential for a dynamic inventory based on vegetable oil consumption. Future studies are proposed to address more influential factors to improve the reliability of the national inventory and refer to big data, rather than door-to-door investigation, to identify the amount of catering service businesses in a region. Unlabelled Image • Intensive surveys on catering industry information performed in two Chinese cities • Survey data help establish a national emission inventory of catering industry. • A significant correlation observed between vegetable oil consumption and emissions. • This correlation indirectly verifies by the rationality of the inventory. • This relation useful for dynamically updating emission inventory of catering sector [ABSTRACT FROM AUTHOR]

The mass absorption efficiency (MAE) and mass scattering efficiency (MSE) of aerosols are critical to their light extinction capacity. In winter in northern China, episodes of clear air and heavy haze alternately occur due to the high primary emission and secondary formation of aerosols, coupled with changing weather conditions. These occurrences facilitate detailed investigation of how significant changes in the pollution level impact the MAE and MSE, they also enable the determination of whether current air quality improvement measures are also beneficial to the mitigation of climate change, to avoid climatic side effects of attempts to clean the air. In the present study, a one-month observation campaign was conducted in Beijing, China, during the 2016–2017 winter season. A photoacoustic extinctiometer, which is an in situ measurement instrument, was used to investigate the aerosol absorption coefficient (σ a) and scattering coefficient (σ s) at an infra-red wavelength of 870 nm. The MAE and MSE were found to vary differently with increasing pollution level. A positive correlation between the particulate matter concentration (PM 2.5) and the MAE was observed for PM 2.5 < 100 μg m−3, with the increase in the MAE declining for PM 2.5 = 100–200 μg m−3, and the MAE subsequently stabilizing. In contrast, the MSE continuously increased with increasing PM 2.5. The single scattering albedo (SSA), which governs the climatic effect of aerosols, was observed to be a function of both σ a and σ s , increasing from 0.827 ± 0.018 (average ± standard deviation) for a bottom particulate matter concentration group of (0, 25] μg m−3 to 0.924 ± 0.007 for a top particulate matter concentration group of (300, 400] μg m−3, indicating a positive correlation between the SSA and PM 2.5. These observations suggest a risk of current clean air measures weakening or eliminating the cooling effect of ambient aerosols in northern China. It seems that no previous study has involved the simultaneous acquisition of σ a and σ s at the same wavelength with the purpose of determining how increasing air pollution differently impacts the MAE and MSE. Practical measures that can be used to decrease the black carbon-to-PM 2.5 ratio include phasing out or reducing black carbon-rich sources and promoting technologies that decrease the black carbon-to-organic carbon ratio. Image 1 • MAE and MSE were found to show different responses to escalating pollution levels. • A risk of weakened cooling effect of ambient aerosol with the clean air process. • Practical solution was proposed to against the risks in China's clean air process. [ABSTRACT FROM AUTHOR]