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GPS IIR-M and IIF satellites have the capability to achieve flex power by distributing transmitting power between different signals, and in general, the power of P(Y) signal is typically improved. Since February 2020, with observations from IGS and iGMAS stations, the IIR-M and IIF satellites of the GPS system have activated flex power almost daily, most of which are regional in nature. To obtain the selected center points of GPS flex power, this paper proposes a method to divide the grid globally, calculate the satellite elevation angles, and perform statistical analysis. This paper verifies the correctness of the proposed method by using simulated data and previous literature data. Moreover, data from February 2020, April 2020, and March 2021 are analyzed and verified in this study. The study of flex power in different periods reveals that the locations of the center points and the way of application are constantly changed, leading to changes in the global availability of flex power.

This paper examines the effect of export stability on income inequality in north and south countries. We use products level data to measure export stability and apply several IV strategies that allows us to estimate the impact of export stability on income with much greater precision. Our main finding is that export stability has a positive effect on the income growth of developing countries but no effect on developed countries, implying that export stability leads to a significant reduction in income inequality between the north and south countries. Furthermore, we show that in developing countries, the effect of export stability operates through an increase in income expectation and inventory management efficiency; the improvement of business environment and product complexity enhances the effect of export stability; the increase of government size may decrease the effect of trade instability. Finally, we show third country effect doesn’t directly influence income growth.

Jiangsu-Zhejiang-Shanghai (JZH) is an important industrial area and foreign trade base in China. In recent years, due to economic development and urban expansion, the emissions of volatile organic compound (VOC) have been increasing, which exacerbated the problem of formaldehyde (HCHO) pollution. The Ozone Monitoring Instrument (OMI) remote sensing has the characteristics of high spatial coverage and strong time continuity, which can enable long-term serial and large-scale dynamic monitoring of atmospheric pollutants. Based on the inversion data of OMI, the paper analyses the temporal-spatial distribution and change trend of the HCHO in JZH from 2008 to 2019, and discusses the transmission path of HCHO in combination with the backward trajectory. In addition, the degree of contribution of anthropogenic sources and natural sources to HCHO are analysed, which is the local HCHO pollution providing reference opinions on governance and atmospheric energy saving and emission reduction. The results showed that the spatial distribution of HCHO in JZH was uneven and will continue to increase in the future. Different types of artificial sources have different degrees of contribution to the study area. In addition, vegetation, temperature, and precipitation have obvious high correlations with HCHO, indicating that natural factors have an important influence on HCHO.

Background: Clear cell renal cell carcinoma (ccRCC) is characterized by glycogen-laden, unexplained male predominance, and frequent mutations in the Von Hippel-Lindau (VHL) gene and histone modifier genes. Besides, poor survival rates of ccRCC patients seem to be associated with up-regulation of the pentose phosphate pathway (PPP). However, the mechanism underlying these features remains unclear. Methods: Whole exome sequencing was used to identify the gene mutation that implicated in the rewired glucose metabolism. RNA-seq analyses were performed to evaluate the function of KDM5C in ccRCC. Furthermore, heavy isotope tracer analysis and metabolites quantification assays were used to study how KDM5C affects intracellular metabolic flux. To provide more in vivo evidence, we generated the Kdm5c-/- mice by CRISPR-Cas9 mediated gene knockout and performed the xenografts with KDM5C overexpressing or depleted cell lines. Results: A histone demethylase gene KDM5C, which can escape from X-inactivation and is predominantly mutated in male ccRCC patients, was identified to harbor the frameshift mutation in the ccRCC cell line with the highest glycogen level, while the restoration of KDM5C significantly reduced the glycogen level. Transcriptome and metabolomic analysis linked KDM5C to metabolism-related biological processes. KDM5C specifically regulated the expression of several hypoxia-inducible factor (HIF)-related genes and Glucose-6-phosphate dehydrogenase (G6PD) that were involved in glycogenesis/glycogenolysis and PPP, respectively, mainly through the histone demethylase activity of KDM5C. Depletion of KDM5C increased the production of glycogen, which was then directed to glycogenolysis to generate glucose-6-phosphate (G6P) and subsequently PPP to produce nicotinamide adenine dinucleotide phosphate hydride (NADPH) and glutathione (GSH), thus conferring cells resistance to reactive oxygen species (ROS) and ferroptosis. KDM5C re-expression suppressed the glucose flux through PPP and re-sensitized cancer cells to ferroptosis. Notably, Kdm5c-knockout mice kidney tissues exhibited elevated glycogen level, reduced lipid peroxidation and displayed a transformation of renal cysts into hyperplastic lesions, implying a cancer-protective benefit of ferroptosis. Furthermore, KDM5C deficiency predicted the poor prognosis, and clinically relevant KDM5C mutants failed to suppress glycogen accumulation and promoted ferroptosis as wild type. Conclusion: This work revealed that a histone modifier gene inactive mutation reprogramed glycogen metabolism and helped to explain the long-standing puzzle of male predominance in human cancer. In addition, our findings may suggest the therapeutic value of targeting glycogen metabolism in ccRCC.

The eastern region is an important economic hinterland and energy region of China; however, the rapid economic development and the decoupling of environmental pressure have resulted in a significant increase in volatile organic compound (VOC) emissions, and the region is facing the air pollution problem of high-concentration formaldehyde accumulation. The Aura/Ozone Monitoring Instrument (OMI) remote sensing satellite can perform long-term and large-scale dynamic monitoring of tropospheric formaldehyde, and its data can reflect the distribution of formaldehyde column concentration in the study area. This article discusses the spatial and temporal characteristics of formaldehyde in eastern China from 2009 to 2018 based on OMI's formaldehyde column concentration data daily products. In addition, based on the Multi-resolution Emission Inventory for China (MEIC), the potential contributions of natural sources (isoprene) and anthropogenic sources (industrial sources, transportation sources, and residential sources) to formaldehyde are analyzed. The results show that the formaldehyde column concentration is higher in eastern China, and the high-value areas are mainly concentrated in regions with close human activities, such as Jing-Jin-Ji (JJJ), the Yangtze River Delta (YRD), and the Pearl River Delta (PRD), and the concentration is predicted to increase slowly in the future. One of the main sources of formaldehyde is isoprene emitted by plants, but the impact of human activities on formaldehyde cannot be ignored. The OMI data can objectively reflect the spatiotemporal distributions and change characteristics of formaldehyde in large areas and effectively characterize the accumulation of atmospheric pollutants; thus, the use of OMI can provide an important theoretical basis and reference value for the improvement of regional ecological environment and atmospheric quality.

The concentration of nitrogen dioxide (NO2) in the air is one of the important indexes for evaluating air quality. At the beginning of 2020, a COVID-19 outbreak suddenly hit Wuhan, China. To effectively control the epidemic, Wuhan was put under a 76-day lockdown, during which we collected tropospheric column amounts in the atmosphere and NO2 concentrations measured at ground monitoring stations, and we reviewed the ground NO2 concentrations in 2019 and the tropospheric NO2 concentrations between 2012 and 2019. Using the random forest (RF) model, we predicted the impact of the tropospheric NO2 concentration during the lockdown period without the occurrence of the COVID-19 epidemic and analyzed the impact of multiple certain meteorological factors on tropospheric and ground NO2 concentrations. The results showed that the tropospheric and ground NO2 concentrations were reduced by 11.04~53.36% and 21.96~65.04%, respectively. The main factors affecting the tropospheric NO2 concentration were wind velocity, land surface temperature, surface lifted index, precipitable water volume and tropospheric relative humanity. The main factors affecting the ground NO2 concentration were tropospheric relative humanity, surface lifted index, land surface temperature and tropospheric temperature. The development of different emission reduction and control measures under different meteorological conditions and the formulation of more refined policies will play positive roles in improving the efficiency of air pollution control.

The Sichuan-Chongqing region is the leader and growth pole of economic development in western China. With the rapid development of economy and unique geographical environment, high concentration of sulfur dioxide air pollution has existed for a long time in Sichuan-Chongqing area. Based on 10 years of remote sensing data, this paper studies the temporal and spatial distribution characteristics, stability, and influencing factors of sulfur dioxide in this area. Based on potential sources, the impact of surrounding areas on sulfur dioxide in Sichuan and Chongqing is analyzed. The results shows that the spatial distribution of sulfur dioxide in the Sichuan-Chongqing region is higher in the southeast and lower in the west. The Midwest region has low fluctuation and good stability. The time distribution shows obvious seasonal regularity. The concentration of sulfur dioxide is affected by socio-economic factors and natural factors. In this study, it is found that the distribution of sulfur dioxide is closely related to PM2.5, which provides an important reference for the comprehensive management of air pollution. The OMI data effectively reflects the distribution and change of atmospheric sulfur dioxide in the Sichuan-Chongqing region, and provides certain ideas for air pollution control in the Sichuan-Chongqing region and other regions in China.

In order to assess the status of aerosol pollution in three selected Northeast Provinces of China, Ozone Monitoring Instrument/Aura Near UV Aerosol Optical Depth and Single Scattering Albedo 1-orbit L2 Swath 13 × 24km V003 (OMAERUV) daily product data was used to evaluate (1) the ultraviolet aerosol index (UVAI) temporal and spatial distribution of the three Northeast Provinces from 2009 to 2018; (2) the potential pollution source areas of provincial capital cities; and (3) future trend changes. Furthermore, the influencing factors were also analyzed and are discussed herein. The results show that the UVAI in the Northeast Provinces exhibit an overall increasing trend, with an average annual increase rate of 2.99%. Seasonally, the UVAI increasing trend in winter is higher than in spring which in turn is higher than autumn. And summer has the least increasing trend. In addition, the external source of absorbent aerosol transmission is mainly in the southwest. Moreover, the overall UVAI remains relatively constant in the central part of the region, and increases slightly and significantly in the south and north directions. In general, spring, autumn, and winter all exhibit increasing trends in varying degrees. The difference between the forecasted and actual UVAI values in the Northeast Provinces does not exceed 10%; thus, the forecasting reliability is good. Also, UVAI has different degrees of correlation with natural factors, such as precipitation and temperature. With respect to social factors, UVAI and population density (a social factor) are positively correlated in 98.2% of the study area, demonstrating that there is a strong positive correlation between UVAI and smoke and dust emissions.

The Sichuan-Chongqing region is the leader and growth pole of economic development in western China. With the rapid development of economy and unique geographical environment, high concentration of sulfur dioxide air pollution has existed for a long time in Sichuan-Chongqing area. Based on 10 years of remote sensing data, this paper studies the temporal and spatial distribution characteristics, stability, and influencing factors of sulfur dioxide in this area. Based on potential sources, the impact of surrounding areas on sulfur dioxide in Sichuan and Chongqing is analyzed. The results shows that the spatial distribution of sulfur dioxide in the Sichuan-Chongqing region is higher in the southeast and lower in the west. The Midwest region has low fluctuation and good stability. The time distribution shows obvious seasonal regularity. The concentration of sulfur dioxide is affected by socio-economic factors and natural factors. In this study, it is found that the distribution of sulfur dioxide is closely related to PM

With the completion of the global constellation deployment of beidou-3, Beidou satellite navigation system has entered the stage of industrial application. In this paper, the business model structure of GPS, GLONASS, Galileo and Beidou system is analyzed from the perspective of resource capacity complementarity and transaction value. Through comparative analysis, this paper studies the interaction, main practices, characteristics and effectiveness of Beidou business model, and discusses the optimization direction of Beidou system business model in the future. It assist Beidou Systems and related companies to optimize their business models and strengthen their competitive advantages in the global GNSS market.

As a significant part of GNSS navigation message, timing group delay is one of the main errors in GNSS applications such as navigation, positioning, timing and ionospheric estimation. DCB solution in One-TGD-fixed constraint condition is more suitable for Beidou regional satellite navigation system, in which the TGD parameter exit calibration value of a certain GEO satellite is fixed as the constraint condition. Based on the global ionospheric map provided by IGS as a reference, monthly TGD parameters in 2019 have been calculated to analyse the characteristics of satellite TGD changes. The results demonstrate that the stability of TGD parameters is from high to low in the order of GEO satellites, MEO satellites and IGSO satellites. The changes of all satellites in a year are within 1ns, and most of them are within 0.5 ns. Monthly changes in TGD-B1B2 are in -1.6 ~ 1.5ns, and TGD-B1B3 are in -1.4 ~ 1.2ns. TGD-B1B3 parameters are more stable than TGD-B1B2 parameters in monthly variation, with maximum changes in a month within 1.6ns for TGD-B1B2 and 1.3ns for TGD-B1B3, average changes in a month within 0.7ns for TGD-B1B2 and 0.5ns for TGD-B1B3.

Cell-loaded carboxymethylcellulose (CMC) microspheres were generated via a flow focusing microfluidic device, with a final aim to obtain viable ATDC5 aggregates with sustained proliferation capacity. We synthesized various CMC with phenolic groups (CMC-Ph) and demonstrated that high CMC-Ph molecular weight, high CMC-Ph concentration (0.8 g/ml) or long culturing period had obvious inhibition effect on ATDC5 proliferation, but low horseradish peroxidase concentration (HRP,0.4 mg/ml) did not. CMC-Ph gels being obtained through HRP/H

A magnetic-pH dual responsive drug delivery system was prepared for antibacterial therapy to reduce the side effects on nonpathological cells or tissues. Iron oxide (Fe3O4) core was surface-functionalized with silane coupling agents to link β‑cyclodextrin (β-CD) (CDMNP), and a polypseudorotaxanes shell where polyethyleneglycol chains threaded much CD molecules was further prepared on the magnetic Fe3O4 core (CDMNP-PEG-CD) to enhance loading capacity of roxithromycin (ROX). CDMNP-PEG-CD with a hydrodynamic diameter of ~168 nm was cytocompatible, superparamagnetic, magnetic-responsive and stable for 180 min of storage. No significant interaction with serum albumin was shown for the nanocomposites. The in vitro release from ROX-loaded CDMNP-PEG-CD nanocomposites was about 76% of total drug within 30 min at pH 1.0, 1.6-fold of that at pH 7.4 and 2-fold of that at pH 8.0, presenting pH-responsive drug release behaviors. The nanocomposites showed positive antibacterial activity against both E. coli and S. aureus based on an agar diffusion method. The antibacterial activity of the nanocomposites was more sensitive against E. coli than S. aureus, and the inhibition halo against E. coli was 85% more than that of Fe3O4. CDMNP-PEG-CD nanocomposites allowed for the localization and fast concentration of hydrophobic drugs, providing a broad potential range of therapeutic applications.

Traditional fingerprint orientation clustering algorithms often use k means clustering algorithm, but as a result of fingerprint and objective factors of volatile characteristics over time, k-means cannot adapt to change at any time in fingerprint, and cannot be generated adaptive clustering cluster number, cause the matching accuracy is not high. This paper adopts a based on support vector machine (SVM) and DBSCAN clustering algorithm, can generate continuously adapt to changing the optimal hyperplane fingerprint model, solved the fingerprint fluctuating lead to the problem of matching result is bad, and can be automatically generated in the process of matching classification number of clusters, based on statistical density characteristics of DBSCAN selection matching probability model, to improve the positioning of the matching accuracy, reduced the amount of time matching positioning, positioning accuracy can be up to 2.04 m in the range of 57%, relative k-means 6.1 m increased by 52.3%, improve the positioning accuracy.

As an important component of the augmentation service, the ionospheric grid contributes to improving single-frequency positioning accuracy. The ionospheric delay corrections are broadcast as vertical delay estimates at specified ionospheric grid points (IGPs) for most satellite-based augmentation system, where the IGPs are predefined with a resolution of 5° and 5° in latitude and longitude. Different from the general strategy, the COMPASS IGPs are predefined with a resolution of 2.5° and 5° in latitude and longitude. The need for this special IGPs distribution is investigated with experiments using real data. The performance of the COMPASS ionospheric grid is analyzed in terms of accuracy and availability. Comparing the performance of the special IGPs distribution with that of 5° × 5° IGPs, the results show that the ionospheric correction improves by 0.2 m and the 3D positioning accuracy improves by 1 m in middle-low latitude regions. The RMS of the COMPASS grid ionospheric correction accuracy is better than 0.5 m in most regions of the China mainland, and the availability is better than 95 % except in the northeast, northwest and outside China. In addition, we investigated the performance of the method that combined the inverse distance weighted and spherical harmonics grid modeling algorithm. Simulations show that the new method clearly improves grid availability. The mean availability in the mainland is better than 99 %.

As an important component of differential navigation service, ionospheric grid can greatly improve the accuracy of single frequency users. Wide-Area Augmentation System (WAAS) broadcasts a set of ionospheric grids data for authorized single frequency GPS users every 300 s. WAAS uses inverse distance weighting (IDW) algorithm to calculate the vertical total electron content (VTEC) at those ionosphere grid points (IGP). IDW algorithm has good correction accuracy, but has low availability in the area with few ionosphere pierce points (IPP). The availability and accuracy of ionospheric grid by IDW algorithm depend on the distribution of monitoring stations and the constellation of navigation system. As the constellation of regional satellite navigation system consists mainly of geostationary earth orbits (GEO) satellites and inclined geosynchronous orbits (IGSO) satellites, the IPPs have a concentrating distribution. Considering that the distribution of monitoring stations are all in China, using IDW algorithm to calculate ionospheric grid will not have good availability. This paper proposes a practical algorithm to calculate the regional ionospheric grid based on spherical harmonics (SH) model and International Reference Ionosphere (IRI-2012) model. Compared with IDW algorithm, the simulation data analysis indicates that the SH algorithm can greatly improve the availability from 82.62 to 99.83 % for mainland China and from 34.66 to 94.25 % for all grids, but the average correction RMS of ionospheric grid increases from 2.60TECU to 3.33TECU.

Ionospheric delay observations of regional satellite navigation system shows heterogeneity in space and time, and it brings difficulties to implement the ionospheric delay model. The Kloubuchar model in geographic coordinates assumes that the ionospheric delay at the same latitude have the consistent variation characteristics with local time. The constellation of COMPASS is mainly composed of GEO satellites. In order to achieve the regional ionospheric delay variation, we can use several GEO ionospheric observations. By selecting 5 observation stations with well-distributed in latitude from 24 stations with COMPASS observations through the year 2012, we adopt polyhedral function fitting and Delaunay triangulation fitting to complement ionospheric observations of the region and period of time without real observations. Then we compute the Kloubuchar model parameters by using the complemented data, and use all 24 stations observations to check the results. Analysis result shows that, in the solar activity peak year, the average correction accuracy of model is prior to 65 % in middle-low latitude area, and RMS (1σ) is better than 11 TECU. The precision improvement is obviously improved compared with results without data complement using polyhedral function fitting.

The connotation of “Going Global” is abundant, which contains goods export, service export, technology export, investment abroad, foreign loans, foreign aid and personnel emigration, etc. Establishing the strategy of “Going Global” is an important part of the domestic overall opening-up strategy. The Chinese enterprises, especially the private enterprises going global and developing international business are imperative under the situation. Currently, how to further improve and perfect the financial service and establish financial support system, to support more private enterprises “going global”, is an important topic we facing.