In this paper, we present long-term observations of atmospheric nitrogen dioxide ( NO 2 ) and formaldehyde (HCHO) in Nanjing using a Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) instrument. Ground-based MAX-DOAS measurements were performed from April 2013 to February 2017. The MAX-DOAS measurements of NO 2 and HCHO vertical column densities (VCDs) are used to validate ozone monitoring instrument (OMI) satellite observations over Nanjing. The comparison shows that the OMI observations of NO 2 correlate well with the MAX-DOAS data with Pearson correlation coefficient ( R ) of 0.91. However, OMI observations are on average a factor of 3 lower than the MAX-DOAS measurements. Replacing the a priori NO 2 profiles by the MAX-DOAS profiles in the OMI NO 2 VCD retrieval would increase the OMI NO 2 VCDs by ∼30  % with correlation nearly unchanged. The comparison result of MAX-DOAS and OMI observations of HCHO VCD shows a good agreement with R of 0.75 and the slope of the regression line is 0.99. An age-weighted backward-propagation approach is applied to the MAX-DOAS measurements of NO 2 and HCHO to reconstruct the spatial distribution of NO 2 and HCHO over the Yangtze River Delta during summer and winter time. The reconstructed NO 2 fields show a distinct agreement with OMI satellite observations. However, due to the short atmospheric lifetime of HCHO, the backward-propagated HCHO data do not show a strong spatial correlation with the OMI HCHO observations. The result shows that the MAX-DOAS measurements are sensitive to the air pollution transportation in the Yangtze River Delta, indicating the air quality in Nanjing is significantly influenced by regional transportation of air pollutants. The MAX-DOAS data are also used to evaluate the effectiveness of air pollution control measures implemented during the Youth Olympic Games 2014. The MAX-DOAS data show a significant reduction of ambient aerosol, NO 2 and HCHO (30 %–50 %) during the Youth Olympic Games. Our results provide a better understanding of the transportation and sources of pollutants over the Yangtze River Delta as well as the effect of emission control measures during large international events, which are important for the future design of air pollution control policies.

The Fengyun-4 (FY-4) satellite series is a new generation of geostationary meteorological satellites from China. The newly adopted three-axis-stabilized attitude-control platform can increase observation efficiency and flexibility while bringing great challenges for image navigation as well as integrated observation mode design. Considering the requirements of earth observation, navigation and calibration as well as observation flexibility, instrument observation strategies are proposed. These include the earth, the moon, stars, cold space, blackbody and diffuser observations on which the instruments' in-orbit daily observations must be based. The most complicated part is the star observation strategy, while navigation precision is dependent on in-orbit star observations. A flexible, effective, stable and automatic star observation strategy directly influences star data acquisition and navigation precision. According to the requirement of navigation, two specific star observation strategies for the two main instruments on board FY-4A were proposed to be used in the operational ground system. The strategies have been successfully used in FY-4A in-orbit tests for more than a year. Both the simulation results and in-orbit application results are given, including instrument observation strategies, star observation strategies and moon observation tasks, to demonstrate the validity of the proposed observation strategies, which lay important foundations for the instruments' daily operation.

This study used carbon (C) isotope sourcing to determine transport processes of dissolved inorganic carbon (DIC) from the land surface to river catchments in Southwest China. Both nested karst watersheds investigated (Chenqi and Houzhai) are representative of typical karst landform environments (e.g., primary forest, secondary forest, and farmland). We measured DIC concentrations and the delta C-13 values of rainfall, river water, groundwater, soil, and plants. To do so, we used IsoSource (a Visual Basic program) to determine source partitioning over time (seasonal) and across the two nested watersheds. In 2017, the mean DIC concentration was 0.06 +/- 0.03 mmol L-1 and the rainfall delta C-13(DIC) value was -14.4 parts per thousand +/- 1.9 parts per thousand. We found similar DIC concentrations in the surface and groundwater of both watersheds, ranging from 0.20 to 0.71 mmol L-1 (seasonal) and from - 3.7 parts per thousand to - 9.4 parts per thousand (delta C-13(DIC)) in the Chenqi catchment and from 0.33 to 0.60 mmol L-1 (seasonal) and from -10.3 parts per thousand to - 6 parts per thousand (delta C-13(DIC)) in the Houzhai watershed. The average delta C-13 values of soil and local plants were - 24.6 +/- 1.4 parts per thousand and - 28.9 +/- 1.2 parts per thousand in the Chenqi catchment and -25.8 +/- 0.9 parts per thousand and - 27.2 +/- 1.8 parts per thousand in Houzhai watershed, respectively. In addition, carbonate bedrock and groundwater were the main sources of surface water in the Chenqi and Houzhai nested watersheds, both being greater than 30%. Source percentages were similar to 20% from atmospheric deposition and similar to 10% from soil. Furthermore, HCO3- was the predominant form of DIC (pH values > 8), and the contribution rates of dissolved carbonate minerals (HCO3-) were approximately 10.4% and 19.6% in the Chenqi catchment and the Houzhai watershed, respectively.

This work is devoted to discussing that how the locations of the thermal and viscous damping affect the stability of the 1-d elastic systems. The spatial domain of the 1-d thermoelastic system under consideration can be divided into three sub -intervals, that is, the thermoelastic region of type II, the one of type II with viscous damping, and the one of type III. The following two kinds of energy decay rates for the system are obtained: 1. If the thermoelastic region of type III includes one exterior point of the spatial domain of the system, the energy of the system decays exponentially; 2. If not, that is the thermoelastic region of type III is strictly inside the spatial domain, the system always lacks of exponential decay. However, the optimal polynomial decay rate is further estimated for this system with smooth initial states. Finally, some numerical simulations are presented to verify the stability results obtained in this work. (C) 2019 Elsevier Inc. All rights reserved.

The steroidogenic acute regulatory protein (STAR) governs the rate-limiting step in steroidogenesis, and its expression varies depending on the needs of the specific tissue. It is well known that tight control of steroid production is essential for multiple processes involved in reproduction. We recently showed that Star is regulated at the posttranscriptional level in vitro by H19 and let-7. Here we demonstrate that this novel regulatory mechanism is functional in vivo, regulated by cAMP, and that loss of H19 not only disrupts ovarian STAR but also results in altered progesterone production in an H19KO mouse model. This work further strengthens the possibility that noncoding-RNA-mediated regulation of STAR may play an important role in the regulation of steroid hormone production, and contributes further to our understanding of the many ways in which this important gene is regulated.