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• Proposed a double-differenced algorithm for 5G to solve the impact of the 5G clock synchronization error on the positioning. • Proposed a positioning model based on the combination of double-differenced 5G and PPP or RTK of GPS. • Investigated the dynamic positioning performance of different combined positioning models under different environments. As the demand for hybrid indoor and outdoor positioning has increased, the research trend in positioning technology has shifted to hybrid positioning technology suitable for complex indoor and outdoor environments. High-precision positioning technology combined with Global Navigation Satellite Systems (GNSS) and fifth-generation mobile communication technology (5G) has many applications in many industries. A double-differenced algorithm applicable to 5G was proposed to solve the impact of the 5G clock synchronization error on the positioning. Double-differenced observations were obtained by introducing reference terminals to eliminate the influence of clock errors on positioning accuracy between terminals and base stations and between base stations and base stations. Then, the dynamic positioning performance of different combined positioning models under different occluded environments was investigated by combining 5G double-differenced observations with undifferenced/double-differenced GPS observations and comparing the positioning results with GPS-only. The results showed that the combined positioning model can achieve more accurate positioning results than a single system in different positioning modes, and the advantages were more evident in the occluded environment. This study provides a reference for hybrid positioning techniques in complex indoor and outdoor environments and promotes further development of seamless indoor and outdoor positioning. [ABSTRACT FROM AUTHOR]

Strong-motion’s baseline shift error is very difficult to process precisely; it is mainly caused by the tilting, rotation of the ground and environment noises during the co-seismic period. In the study, we first studied how to effectively extract the strong-motion’s baseline shift error with GPS observation; this also provides a new way of correcting the baseline shift errors. Then we studied how to retrieve the ground tilting information of the station point with the collocated GPS and strong-motion observations, the information is an important input parameter of rotational seismology. In addition, both experimental result and seismic data show that the baseline shift error is mainly caused by the ground tiling and rotation during the co-seismic period. Also, there is a strong directly proportional relationship between the baseline shift error and ground tilting, of which the proportionality constant is approximately equal to the value of gravitational acceleration of the station. [ABSTRACT FROM AUTHOR]

This paper has studied the key issues about integration of GNSS and strong-motion records for real-time earthquake monitoring. The validations show that the consistence of the coordinate system must be considered firstly to exclude the system bias between GNSS and strong-motion. The GNSS sampling rate is suggested about 1–5 Hz, and we should give the strong-motion’s baseline shift with a larger dynamic noise as its variation is very swift. The initialization time of solving the baseline shift is less than one minute, and ambiguity resolution strategy is not greatly improved the solution. The data quality is very important for the solution, we advised to use multi-frequency and multi-system observations. These ideas give an important guide for real-time earthquake monitoring and early warning by the tight integration of GNSS and strong-motion records. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Ga is successfully incorporated into MFI zeolites frameworks without GaO x species. • The ratios of Weak/Strong acid sites dominated propene/ethylene ratios in MTP products. • The ratios of Lewis/Brönsted acid sites determined lifetime of MFI-zeolites. • The alkene/aromatics cycles co-exist during MTP process over GaS-1. • The weaker acidity induced by Ga doping boosts alkene cycle and propene generation. Optimising the balance between propene selectivity, propene/ethene (P/E) ratio and catalytic stability and unravelling the relationship between the acidity of MFI-zeolites and those performances are challenging goals of great importance in state-of-the-art methanol-to-olefin (MTO) research. We report a strategy to finely control the acidity of MFI-zeolites by incorporating gallium(III) centres into Silicalite-1 (S-1), obtain an optimal GaS-1(1.3) zeolite through optimizing the gallium content by hydrothermal method·NH 3 -TPD and pyridine-IR reveal that the ratios of Weak/Strong acid sites (W/S ratios) dominates P/E ratios, while the ratios of Lewis/Brönsted acid sites (L/B ratios) determines lifetime of MFI-zeolites during MTP process. The resultant GaS-1(1.3) zeolite exhibits simultaneously remarkable propene selectivity (45.3 %), P/E ratio (14.6) and catalytic stability (>180 h) at full methanol conversion. Compared with HZSM-5 zeolite, the acidity could be weakened by Ga substitution and the optimization of Ga coordination structure creates an optimal acidity for efficient conversion of methanol and thus greatly promotes the application of zeolites in the sustainable manufacturing of light olefins. [ABSTRACT FROM AUTHOR]

Double emulsions have very promising application prospects in the pharmaceutical, cosmetic, and food industries. Nevertheless, its usage in the food industry is restricted mainly due to its immense stability problems. Here, W 1 /O/W 2 double emulsion was prepared by two-step emulsification method using ultrasonic emulsification technology. The physicochemical stability, rheological properties, thermal stability, and microstructure of the double emulsion were investigated. The results revealed that W 1 /O/W 2 double emulsion with optimum stability was prepared on the parameters that the ratio of W 1 (gelatin)/O primary emulsion to the external aqueous phase (gelatin-EGCG-high methoxyl pectin ternary complex) was 6:4, ultrasonic power was 80 W, ultrasonic time was 6 min, and ternary complex concentration was 0.75%. The double emulsion produced under these conditions had the smallest particle size (1143 nm) and the maximum absolute zeta potential value (39.17 ± 0.50 mV). The results of full-featured stability analyzer manifested that the emulsion system no longer underwent phase separation. Confocal laser scanning microscopy (CLSM) successfully observed a uniformly dispersed double emulsion. Furthermore, dynamic rheological properties demonstrated that the cohesive strength of W 1 /O/W 2 double emulsion was strength than that of W 1 /O primary emulsion. Differential scanning calorimetry (DSC) analysis suggested that both remained stable throughout the temperature change, while the W 1 /O/W 2 double emulsion was more thermally stable. Hence, the gelatin-EGCG-high methoxyl pectin ternary complex can act as an effective emulsion stabilizer to stabilize the W 1 /O/W 2 double emulsion. [Display omitted] • W/O/W double emulsions were prepared by ultrasonic emulsification method. • Ultrasonic treatment improves the physical stability of the emulsion. • The optimally stable double emulsion system no longer exhibits phase separation. • Ternary complex can be used as emulsion stabilizer to stabilize double emulsion. • Cohesive strength of the double emulsion is enhanced after ultra-sonication. [ABSTRACT FROM AUTHOR]

Background: To investigate the roles of androgen receptor (AR) in epithelial- mesenchymal transition (EMT) in human prostate cancer stem progenitor (S/P) cells isolated from LNCaP cell line. Methods: The S/P cells were obtained from LNCaP cell line through florescence-activated cell sorting (FACS). AR was overexpressed in S/P cells through lentivirus. Western blot assay was used to detect the EMT markers expression, such as E Cadherin, N Cadherin, Vimentin and Snail. MTT assay, soft agar colony formation assay, sphere formation assay and migration assay were used to investigate AR's roles in EMT of S/P cells. Cell signaling pathways associated with proliferation and apoptosis of S/P cells were detected simultaneously. And S/P cells were treated with in vitro combinatory use of LY 294002 (inhibitor of AKT signaling molecules) with γ-TT and/or 5-AZA. Results: Our data showed that S/P cells from LNCaP had high EMT markers expression, more tumorigenesis and strong migration ability. And in S/P cells overexpressed with AR, the expression of EMT markers decreased. In addition, these cells had less proliferation ability, tumorigenesis ability, self-renewal and migration ability. At the same time, targeting S/P cells with AKT signaling pathway inhibitor LY29004 and?-TT and/or 5-AZA could inhibit S/P cell's proliferation and tumorigenesis. Conclusions: Our data suggest that AR played a negative role in EMT of PCa S/P cells, by regulating AKT cell signaling pathway, which could be a new strategy to treat castration resistant prostate cancer (CRPC). [ABSTRACT FROM AUTHOR]

The description of static displacements associated with earthquakes is traditionally achieved using GPS, EDM or InSAR data. In addition, displacement histories can be derived from strong-motion records, allowing an improvement of geodetic networks at a high sampling rate and a better physical understanding of earthquake processes. Strong-motion records require a correction procedure appropriate for baseline shifts that may be caused by rotational motion, tilting and other instrumental effects. Common methods use an empirical bilinear correction on the velocity seismograms integrated from the strong-motion records. In this study, we overcome the weaknesses of an empirically based bilinear baseline correction scheme by using a net-based criterion to select the timing parameters. This idea is based on the physical principle that low-frequency seismic waveforms at neighbouring stations are coherent if the interstation distance is much smaller than the distance to the seismic source. For a dense strong-motion network, it is plausible to select the timing parameters so that the correlation coefficient between the velocity seismograms of two neighbouring stations is maximized after the baseline correction. We applied this new concept to the KiK-Net and K-Net strong-motion data available for the 2011 Mw 9.0 Tohoku earthquake. We compared the derived coseismic static displacement with high-quality GPS data, and with the results obtained using empirical methods. The results show that the proposed net-based approach is feasible and more robust than the individual empirical approaches. The outliers caused by unknown problems in the measurement system can be easily detected and quantified. [ABSTRACT FROM PUBLISHER]

Global Positioning System (GPS) has been proven to be an effective tool to retrieve high-precision displacement for the natural hazard monitoring. The network positioning and Precise Point Positioning (PPP) are the two basic approaches for its data solution, but the former one can only get a relative displacement within the local reference frame and requires a complex and continuously linked infrastructure, and the latter one with a long convergence time to obtain the absolute displacements within the global reference frame. To overcome these drawbacks, this paper proposed a method of fast determining the displacement by PPP velocity estimation (PPPVE). The key of the approach is that the velocity vector parameters are not correlated with other unknown parameters, such as ambiguities and atmosphere, so they can be fast and accurately estimated and integrated into displacements. The validation shows that the displacement can be provided with a precision of 1–2 cm in 1 min by PPPVE. In additional, the Kalman smoothing estimation can be used to improve the PPP solution. [ABSTRACT FROM AUTHOR]

Highlights: [•] N diffusion from anatase surface to the sub-surface is the most difficult. [•] It is easier for a N atom diffusing out of the bulk. [•] N doping from a (101) surface is relatively easier. [•] N doping from a (100) surface is the relatively difficult. [ABSTRACT FROM AUTHOR]

The fast motion of low Earth orbit (LEO) satellites provides rapid geometric changes in a short time, which can accelerate the initialization of precise point positioning (PPP). The rapid convergence of ambiguity parameters is conducive to the rapid success of ambiguity fixing. This paper presents the performance of single- and four-system combined PPP Ambiguity Resolution (AR), enhanced with an ambiguity-float solution LEO. Two LEO constellations were designed: L was a typical polar orbit constellation, with a higher number of visible satellites at high latitudes than at low and middle latitudes; and M was designed to compensate for the lack of visible satellites at low and middle latitudes. The ground observation data of the LEO satellites at the MGEX stations were simulated. Because the global navigation satellite systems (GNSSs) were fully operational, the GNSS data were real observation data from the MGEX stations. Based on the daily observation datasets collected at 258 stations in the global MGEX observation network over three days (from 1 January to 3 January 2022), in addition to the LEO simulation data, we evaluated the positioning performance of LEO ambiguity-float solution-enhanced PPP ambiguity resolution and compared it with LEO-enhanced PPP. The L+M mixed constellation was able to reduce the time to first fix (TTFF) of the four-system combined PPP-AR to 5 min, and four LEO satellites were sufficient to achieve this. L+M mixed constellation was able to reduce the convergence time of the four-system combined PPP to 2 min. Unlike PPP-AR, PPP required more LEO satellites for augmentation to saturate. [ABSTRACT FROM AUTHOR]

• Proposed a combined positioning algorithm with BDS and 5G that is based on raw observations. • It is suitable for the environment with the geometric distribution of satellites was uneven or the number of visible satellites was insufficient. • Positioning algorithm of TDOA based on 5G millimeter wave. In environments such as urban canyons and indoor environments, an insufficient number of visible satellites can degrade the positioning performance of the BeiDou Navigation Satellite System (BDS). Thus, a positioning algorithm that combines the BDS and 5G technology was developed based on raw observation data. Three different satellite occlusion environments were simulated to compare the effects of factors such as the number of base stations and geometric configurations on the positioning performance. The experimental results revealed that the introduction of 5G base stations effectively increased the positioning accuracy and reliability under different occlusion conditions. Additionally, increasing the number of base stations and optimizing the geometric configuration further improved the accuracy and reliability of fusion localization. Moreover, the positive effects of the introduction of 5G base stations were stronger under more severe satellite occlusion conditions. In the future, this fusion positioning algorithm is expected to facilitate the realization of seamless indoor and outdoor positioning. [ABSTRACT FROM AUTHOR]

Six iridium(III) complexes have been designed, synthesized and characterized. The structures of complexes 1–3 were determined by single crystal X-ray diffraction. The complexes 1 and 2 could distinguishing homocysteine from cysteine and glutathione by photoluminesecent signal with a luminescent variation from orange red to green and a large blue shift from 604 nm to 498 nm. [Display omitted] • Six iridium(III) complexes have been designed, synthesized and characterized. • Complex 1 and 2 can distinguish Hcy from Cys and GSH in photoluminesecent signal. • The emission peak underwent a large blue shift of ca.106 nm. • Strong electron-donating effect of amino group was important in the recognition of Hcy. • Sensing mechanism of complex 1 with Hcy was explored by density functional theory. In this work, six iridium(III) complexes have been designed, synthesized and characterized. The molecular structures of complex 1 ([(pba) 2 Ir(bpy-2N(CH 3) 2)]PF 6), 2 ([(pba) 2 Ir(bpy-2NH 2)]PF 6) and 3 ([(pba) 2 Ir(bpy-2CH 3)]PF 6) were determined by single crystal X-ray diffraction. Upon addition of Hcy (homocysteine) to the solution of complex 1 , a luminescent variation from orange red to green was observed by the naked eye, corresponding to a large blue shift from 604 nm to 498 nm (~106 nm). While the emission intensity of complex 1 was almost no change after addition of other common amino acids including Cys (cysteine) and GSH (glutathione). The aldehyde group of complex 1 formed a new thiazinane/thiazolidine ring with Hcy/Cys confirmed by 1H NMR and high-resolution mass spectrometry. And the new product 1 -Hcy had a higher quantum yield than 1 -Cys. Theoretical calculations showed that the HOMO (highest occupied molecular orbital) of 1 -Hcy was located on the newly formed six-membered thiazinane ring, which was different from the HOMO of 1 -Cys. Compared with the other iridium(III) complexes, we can speculate that the large blue shift and enhancement of the emission intensity of the complex 1 were related to the strong electron donating ability of the modified amino groups on bipyridine ligand. This will provide an idea for the design of ratio-based luminescence probes for Hcy in future. [ABSTRACT FROM AUTHOR]

During the fetal development stage, the Central Nervous System (CNS) is particularly sensitive to methylmercury (MeHg). However, the mechanism underlying the antagonistic effect of selenium (Se) on MeHg toxicity is still not fully understood. In this study, female rat models with MeHg and Se co-exposure were developed. Pathological changes in the cerebellum and differential mRNA expression profiles in offspring rats were studied. In the MeHg-exposed group, a large number of Purkinje cells showed pathological changes and mitochondria were significantly swollen; co-exposure with Se significantly improved the structure and organization of the cerebellum. In total, 378 differentially expressed genes (DEGs) (including 284 up-regulated genes and 94 down-regulated genes) in the cerebellum of the MeHg-exposed group and 210 DEGs (including 84 up-regulated genes and 126 down-regulated genes) in the cerebellum of the MeHg+Se co-exposed group were identified. The genes involved in neurotransmitter synthesis and release and calcium ion balance in the cerebellum were significantly up-regulated in the MeHg-exposed group. These genes in the MeHg+Se co-exposed group were not changed or down-regulated. These findings demonstrate that the neurotoxicity caused by MeHg exposure is related to the up-regulation of multiple genes in the nerve signal transduction and calcium ion signal pathways, which are closely related to impairments in cell apoptosis and learning and memory. Supplementation with Se can mitigate the changes to related genes and protect neurons in the mammalian brain (especially the developing cerebellum) from MeHg toxicity. Se provides a potential intervention strategy for MeHg toxicity. [Display omitted] • MeHg exposure causes cerebellar injury and alteration of mRNA expression profile. • Se alleviate the cerebellar damage of the offspring rat caused by MeHg exposure. • Co-exposure to MeHg and Se alters the DEGs caused by MeHg damage. [ABSTRACT FROM AUTHOR]