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To guarantee the integrity of a global navigation satellite system (GNSS) for safety-critical users, a satellite-based augmentation system (SBAS) makes use of the integrity monitoring architecture, of which the signal quality monitor (SQM) is an important component to address the potential risks caused by satellite-induced signal anomalies. Due to the introduction of dual-frequency multi-constellation (DFMC) techniques in 2025, the ranging uncertainty will be reduced by the elimination of first-order ionospheric delay, but the biases measured in each individual signal will be inflated by the ionosphere-free combinations. Moreover, multiple modulations of DFMC signals might introduce applicability uncertainty of a traditional SQM method that has been protecting GPS L1C/A signal only. Thus, higher requirements are put forward for future SQM methods in detection sensitivity and modulation independence. This paper first proposes a design methodology for the SQM algorithm for BDS B1C/B2a signals, which could be easily extended to the DF combinations of other GNSS core constellations. Then, by comparing the performances of SQM baseline algorithms based on traditional multi-correlator and emerging chip domain observables (CDOs), respectively, the superiority of CDO-based SQM is declared. Detailed design iterations are further discussed, including the algorithm practicalization with optimizing code-phase bin length and lowering sampling frequency, as well as the metric simplification, to promote the overall performance while preserving a lower implementation complexity. Ultimately, a CDO-based SQM algorithm for BDS B1C/B2a signals is reached, which would be considered as an effective candidate in new generation DFMC SBASs. [ABSTRACT FROM AUTHOR]

Tracking ambiguity and multipath are two serious threats in processing binary offset carrier (BOC) signals that are widely used in global navigation satellite systems (GNSS). Three-loop tracking methods, such as dual binary phase-shift keying tracking (DBT), use a delay lock loop (DLL), a phase lock loop (PLL), and a subcarrier PLL (SPLL) to track the code, carrier, and subcarrier, respectively, thus solving the tracking ambiguity problem. However, the multipath remains an important factor in the ranging performance deterioration of these tracking methods. Using the offset correlator (OC) technique in the SPLL can effectively mitigate subcarrier multipath errors, but it substantially raises thermal noise errors. To solve this contradiction, this paper proposes a prompt-assisted-offset correlator (PAOC) technique that combines the prompt and offset correlators in a complementary way to mitigate multipath for BOC signals. Compared with the original OC technique, the PAOC technique has less thermal noise performance loss. Moreover, this paper discovers and quantifies the interaction between carrier and subcarrier multipath errors by analyzing the coupling effect between SPLL and PLL. Most multipath mitigation methods for BOC signals ignore the carrier multipath in the PLL, so their subcarrier multipath performance is not optimal. Thus, this paper further proposes applying the PAOC technique in both PLL and SPLL to mitigate carrier and subcarrier multipath errors simultaneously. Theoretical analysis and experimental results demonstrate that the proposed method can significantly improve the multipath performance with small noise performance loss. [ABSTRACT FROM AUTHOR]

It is well known that for binary offset carrier (BOC) signals the notorious ambiguity problem due to the multipeaked autocorrelation function must be tackled first in order to obtain the potential of improving ranging performance promised by its broader Gabor bandwidth. The existence of multipath makes it more difficult to solve. Dual binary phase-shift keying (BPSK) tracking (DBT) is a kind of low complexity, unambiguous tracking method for BOC-family signals, which makes full use of the coherence between the upper and lower sidebands and employs subcarrier phase locked loop (SLL) and delay locked loop (DLL) to track subcarrier and code components, respectively. Considering that the thermal noise performance of DBT has been fully studied, this article focuses on the analysis of multipath performance and the design of antimultipath methods under DBT framework. The influence of multipath on SLL and DLL of DBT is analyzed first and the corresponding subcarrier and code multipath error envelopes are obtained. Then according to different requirements of subcarrier and code multipath errors, a multipath mitigation scheme specially designed for DBT is proposed, in which SLL and DLL adopt offset correlator and narrow correlation, respectively. Theoretical analysis and simulation are given to verify the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Foamed concrete (FC) was prepared from raw materials of vanadium tailings (VTs), reservoir sediment (RS), and phosphogypsum (PG). The physicochemical properties of the raw materials were studied by using X-ray diffraction (XRD), X-ray fluorescence (XRF) analysis, and inductively coupled plasma emission spectrometer (ICP-OES). The preparation and properties of FC were investigated by particle size analysis and strength test. The hydration products and microstructure of FC were analyzed by XRD and field emission scanning electron microscopy (FE-SEM). The results show that when the specific surface area (SSA) of VTs is 768 m2·kg−1 and the content is 40%, the products with a compressive strength of 3.56 MPa and density of 619.1 kg·m−3 meet the requirements of JG/T 266-2011 standard on FC of grades A06 and C3.0; the main mineral phases in the products are calcium silicate hydrate (C-S-H) gel, ettringite (AFt), and calcite, as well as the residual mineral phases after the system reaction include quartz, orthoclase, mullite, pyrite, and PG. [ABSTRACT FROM AUTHOR]

In conventional global navigation satellite system (GNSS) receivers, full pseudorange measurements are usually required to complete a single point position fix, which takes longer time than obtaining fractional pseudorange measurements. In order to shorten the time to first fix and improve the position accuracy during cold or warm start of a dual-constellation GNSS receiver, we propose a positioning algorithm using at least four full pseudorange measurements from one constellation and fractional measurements from either or both constellations. Theoretical rapid position results can be obtained with an identical accuracy to that of the conventional method using full measurements. Tests with simulated and real Global Positioning System (GPS) and BeiDou Navigation Satellite System (BDS) data validate the performance of the proposed approach. [ABSTRACT FROM AUTHOR]

Spatiotemporal information plays crucial roles in a multiagent system (MAS). However, for a highly dynamic and dense MAS in unknown environments, estimating its spatiotemporal states is a difficult problem. In this article, we present BLAS—a wireless broadcast relative localization and clock synchronization system to address these challenges. Our BLAS system exploits a broadcast architecture, under which a MAS is categorized into parent agents that broadcast wireless packets and child agents that are passive receivers, to reduce the number of required packets among agents for relative localization and clock synchronization. We first propose an asynchronous broadcasting and passively receiving protocol. The protocol schedules the broadcast of parent agents using a distributed time division multiple access scheme and delivers interagent information used for joint relative localization and clock synchronization. We then present distributed state estimation approaches in parent and child agents that utilize the broadcast interagent information for joint estimation of spatiotemporal states. The simulations and real-world experiments based on ultra-wideband illustrate that our proposed BLAS can not only enable accurate, high-frequency, and real-time estimation of relative position and clock parameters but also support theoretically an unlimited number of agents. [ABSTRACT FROM AUTHOR]

The interaction between a screw dislocation and an elliptical hole with two asymmetrical cracks in a one-dimensional (1D) hexagonal quasicrystal with piezoelectric effect is considered. A general formula of the generalized stress field, the field intensity factor, and the image force is derived, and the special cases are discussed. Several numerical examples are given to show the effects of the material properties and the dislocation position on the field intensity factors and the image forces. [ABSTRACT FROM AUTHOR]

Two lanthanide complexes [Y(PANH) 3 ]·3H 2 O (1) and [Er(PANH) 3 ]·(CH 3 OH)·(H 2 O) (2) have been constructed from the designed 2-carbonyl propionic acid-4-nitro benzoyl hydrazone ligand, with their structures are all 3D supramolecular network consisting of zero-dimensional structures. The stacking structure of [Y(PANH) 3 ]·3H 2 O (1) contains narrow 1D channels with a opening of 5.49 Å × 6.41 Å along the c axis. Two lanthanide complexes [Y(PANH) 3 ]·3H 2 O (1) and [Er(PANH) 3 ]·(CH 3 OH)·(H 2 O) (2) further characterized by thermogravimetric analyses (TGA) and infrared spectrum (IR). The optical properties are studied by ultraviolet spectrum and fluorescence spectra. Moreover, Fusarium solani was selected as representative to explore the antibacterial activity of the PANH ligand and the lanthanide complexes. Establish the theoretical foundation for development of Salvia Miltiorrhiza Chinese medicinal crop. In this dissertation, based on the designed 2-carbonyl propionic acid-4-nitro benzoyl hydrazone (PANH), two novel lanthanide complexes are prepared, namely, [Y(PANH) 3 ]·3H 2 O (1) and [Er(PANH) 3 ]·(CH 3 OH)·(H 2 O) (2). Their crystal structures are determined by single crystal X-ray diffraction and further characterized by thermogravimetric analyses (TGA) and infrared spectrum (IR). Structural analyses of 1 and 2 showed that they are all 3D supramolecular networks consisting of zero-dimensional mononuclear structures connected by hydrogen bonds. Interestingly, the stacking structure of 1 contains narrow 1D channels with a opening of 5.49 Å × 6.41 Å along the c axis. The optical properties are studied by ultraviolet spectrum and fluorescence spectra. Moreover, Fusarium solani was selected as representative to explore the antibacterial activity of the PANH ligand and the lanthanide complexes. Experimental results show that both PANH ligand and two lanthanide complexes had excellent inhibiting effect on F. solani , and the complexes are obviously more effective in suppressing F. solani than the ligand. [ABSTRACT FROM AUTHOR]

The fast growing exotic Sonneratia apetala had been widely used to restore the mangroves in China. Planted mangroves play important roles in enhancing carbon sequestration and nutrient storage. The contents and pools of soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) of simultaneously planted exotic S. apetala and native mixing mangrove (Avicennia marina , accompanied by Aegiceras corniculatum and Kandelia obovata) were quantified to evaluate the ecological restoration effects. Comparing with unvegetated mudflat, the colonization of mangrove can increase the SOC content within 60 cm and total nitrogen contents within 40 cm. No significant differences existed between S. apetala and native mangrove communities for the SOC, TN and TP contents. The restoration of mangrove forests enhanced the soil carbon stock relative to mudflat but significant differences existed only between native mangrove and mudflat. The TN and TP pools were not impacted by the plantation of mangroves. Therefore, plantation of S. apetala less than two decades did not show any advantages on the stocks of organic carbon and nutrients. The mixing native mangrove community should be recommended to enlarge the area of mangrove and enhance the carbon stock capability in the future. • Contents and pools of SOC, TN and TP in short-term planted exotic Sonneratia apetala and native mangroves were studied. • The mangrove can increase the SOC content within 60 cm and total nitrogen contents within 40 cm. • The mangrove forests increased soil carbon stock but significant difference exist only between native mangrove and mudflat. • The TN and TP pools were not impacted by the short-term plantation of mangroves. [ABSTRACT FROM AUTHOR]

This paper mainly studies the phenomenon of inverse stochastic resonance induced by non-Gaussian noise in a representative Hodgkin–Huxley model. Firstly, spiking manners of neurons under different input currents are investigated and different current thresholds and bifurcation diagram are given. Besides, the limit cycle with different input current are plotted. Then, taking the average firing rate as a measurement, the result shows that a minimum exists in the curve corresponding to the intensity, correlation time and deviation coefficient of non-Gaussian noise, which is named inverse stochastic resonance(ISR). More important, it is found that the mean firing rate will remain unchanged with noise intensity and deviation coefficient when correlation time is sufficiently large and finally trends toward a constant value which is completely determined by input current. Further, the present results will be benefit to investigate the functional roles of randomness in neural spiking. [ABSTRACT FROM AUTHOR]

Mangrove wetlands and terrestrial forests are considered as important carbon sinks for alleviating climate changes, but the sequestration processes and regulations of climate factors on controlling the variability of carbon fluxes of these ecosystems may differ. In order to compare the different mechanisms of carbon sequestration in mangrove and terrestrial forest ecosystems, we analyzed ecosystem CO 2 flux data measured by eddy covariance (EC) technique from four forests ecosystems in subtropical China: two mangrove wetlands and two terrestrial forests. Our results showed that the mangrove wetlands could sequester much more carbon than the nearby terrestrial forests because of significantly higher gross ecosystem production (GEP) and lower ecosystem respiration (Re) values. Moreover, our analysis of the responses of net ecosystem exchange (NEE) to photosynthetically active radiation showed that the mangrove wetlands had lower light compensation point but higher maximum photosynthesis rates than the terrestrial forests. Furthermore, the relationships between Re and air temperature (T air ) showed the ecosystem respiration rate (Re ref ) at 20 °C values were lower but that the temperature sensitivity (Q 10 ) values were higher in the mangrove wetlands than in the terrestrial forests, which might be caused by tides in the mangrove ecosystems. In addition, the relationships between the logarithmic values of soil organic carbon ln(SOC) and δ 13 C indicated that SOC decomposition rates were lower in mangrove forests than in terrestrial forests, which thus led to lower Re values compared to terrestrial forests. Our results imply that mangrove forests can sequester more CO 2 from the atmosphere than nearby terrestrial forests due to relatively higher GEP and lower Re values. Moreover, the regulation of ecosystem carbon exchange by tides in mangrove wetlands should be investigated in more detail in future studies. [ABSTRACT FROM AUTHOR]

A supramolecular polycatenane stabilized by outer surface interactions between cucurbit[6]uril (Q[6] or CB[6]) cations and [CdCl4]2− is reported. The arrangement of the poly-interlocked supramolecular framework is evidently constructed by a favorable combination of weak non-covalent interactions such as hydrophobic effects, hydrogen bonding, ion-dipole interactions, and C−H⋅⋅⋅Cl interactions in the solid state. Further study suggests that such 3D poly-interlocked species could be rapidly precipitated from the mixture solution in high yield owing to electrostatic interaction of the [CdCl4]2− anion with the electropositive outer surface of Q[6] host. This work thus demonstrates a simple, low-cost, and efficient non-covalent approach for the construction of a infinite 3D interlocked structure in water besides through coordination or covalent bonds. [ABSTRACT FROM AUTHOR]

Over the past decade has been a dramatic increase in the international student population at U.S. universities with the total enrollments at many colleges having doubled or quadrupled within the span of a few years. Despite the size and scale of these transformations, there remains little situated research attending to how this population's home languages or grassroots literacies mediate their transitions into the university. To understand this process, this study attends to ways an online chat room called QQ mediates the students’ transition into a large Midwestern public university. In performing this work, the present study contributes to current scholarship on IMing and to what Haas, Carr, and Takayoshi (2011) characterize as interactive networked writing (INW). Given the centrality of INWs in students’ everyday lives, attention to this area is key for understanding how their out-of-school literacies afford and constrain their academic socialization and learning. This exigency is particularly critical in relation to transnational students, as the extant INW scholarship has focused primarily on English with limited attention to practices in other languages beyond North American borders. [ABSTRACT FROM AUTHOR]

Spatial frequency adaptive processing (SFAP) is the dimension‐reduced alternative of spatial temporal adaptive processing (STAP), which can achieve good interference mitigation capability with less computational cost. However, just as STAP, the biases of the ranging code phase and carrier phase induced by the adaptive array restrict SFAP from being applied in high‐precision global navigation satellite system receivers. To address this issue, a new data‐oriented calibration method is proposed. Unlike previous bias reduction methods, which compensate the measurement biases with estimated values in the tracking loop, this method carries out calibration directly on the received data in the frequency domain, thus avoids modification to the rest parts of the receiver other than the SFAP module. The calibration value in each frequency bin is determined from the transfer function of the SFAP array. Simulations are performed on a practical array antenna designed by the high‐frequency structure simulator software with high fidelity, and the results verify the effectiveness of this method. [ABSTRACT FROM AUTHOR]

Co-existence of polycyclic aromatic hydrocarbons (PAHs) and multi-metals challenges the decontamination of large-scale contaminated sites. This study aims to comprehensively evaluate the remediation potential of intensified phytoremediation in coping with complex co-contaminated soils. Results showed that the removal of PAHs and heavy metals is time-dependent, pollution-relevant, and plant-specific. Removal of sixteen PAHs by Medicago sativa L. (37.3%) was significantly higher than that of Solanum nigrum L. (20.7%) after 30 days. S. nigrum L. removed higher amounts of Cd than Zn and Pb, while M. sativa L. uptake more Zn. Nevertheless, amendments and microbial agents significantly increased the phytoremediation efficiency of pollutants and shortened the gap between plants. Cd removal and PAHs dissipation reached up to 80% and 90% after 90 days for both plants. Heavy metal stability in soil was promoted after the intensified phytoremediation. Plant lipid peroxidation was alleviated, regulated by changed antioxidant defense systems (superoxide dismutase, peroxidase, catalase). Soil enzyme activities including dehydrogenase, urease, and catalase increased up to 5-fold. Soil bacterial diversity and structure were changed, being largely composed of Proteobacteria, Actinobacteria, Patescibacteria, Bacteroidetes, and Firmicutes. These findings provide a green and sustainable approach to decontaminating complex-polluted environments with comprehensive improvement of soil health. [Display omitted] • Amendments and microbes significantly improved PAHs dissipation and metal removal. • Additions reduced Cd, Pb, Zn availability, shortened plant gap for phytoremediation. • Additions relieved plant oxidative stress to elevate tolerance to co-contamination. • Soil micro-ecology was promoted physichemically, biochemically and genetically. • Soil bacterial community diversity was dramatically increased. [ABSTRACT FROM AUTHOR]

Plastics are the fastest growing engineering material in the world in the past 50 years. However, with the wide use of plastics, severe environmental problems have also emerged. A dynamic material flow analysis (MFA) of six polymers (polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC)), acrylonitrile butadiene styrene (ABS) and polyethylene terephthalate (PET)) in China was carried out in this study. The dynamic evolution of plastic material metabolism in a long period of time (1950–2020) was tracked, and the scenario of plastic material metabolism in the medium and long term (2021–2050) was analyzed. The results showed that from 1950 to 2020, 2347.3 Mt of plastics were consumed and 1420.8 Mt of plastic wastes were generated, out of which 24.7% were recycled, 18.8% were incinerated, 39.6% were landfilled and 16.8% were discarded. The largest plastic wastes were waste plastic packaging and construction materials represented the largest in-use stocks. In the future, the in-use stocks in 2050 will be about twice that in 2020. Based on these results, this study could provide a scientific basis for reducing the resource and environmental impact of plastic material metabolism, and promote the sustainable production and consumption of plastics in China. A dynamic MFA model is used to analyze stocks and flows of plastics in China. Six of the most used polymers were analyzed: PE, PP, PS, PVC, ABS and PET. The in-use stock of plastics reached 926.5 Mt in 2020. 24.7% of waste plastics were recycled from 1950 to 2020. Secondary plastics could supply 49.1% of plastic demand by 2050. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adsorption and catalysis of BPA synergistically occurred in Fe 3 O 4 -BC/PMS system. • The biochar obtained by the pyrolysis of deciduous leaves of Platanus orientalis. • The enrichment of BPA on the surface was realized because of the biochar. • SO 4 •- was the mainly reactive radical species in Fe 3 O 4 -BC/PMS system. • Fe 3 O 4 -BC composite remained highly efficient in reuse experiments. The nanoFe 3 O 4 -biochar (Fe 3 O 4 -BC) heterogeneous catalyst was synthesized by coprecipitation method and the mechanism of Fe 3 O 4 -BC/peroxymonosulfate (Fe 3 O 4 -BC/PMS) system adsorption and synergistic catalysis for the removal of bisphenol A (BPA) were studied. The effect of initial pH, Fe 3 O 4 -BC load, PMS concentration on the catalyst activity were systematically evaluated. The results showed the synergistic effect between BC and Fe 3 O 4 can greatly improve the removal efficiency of BPA in the Fe 3 O 4 -BC/PMS system. BPA removal efficiency gained 100% in 90 min at pH 3.0 with PMS 5 mM, Fe 3 O 4 -BC load 2.0 g/L and BPA 20 mg/L. Sulfate radical (SO 4 •−) and hydroxyl radicals (•OH) was determined as the reactive species in the Fe 3 O 4 -BC/PMS system, and SO 4 •− was the major reactive species. Fe 3 O 4 -BC remained high active and the iron loss was only 2.13 mg/L when the pH was 3.0 after five recycles, which indicates that Fe 3 O 4 -BC catalyst has a good reusability potential and practical applications. [ABSTRACT FROM AUTHOR]

Abstract: A life cycle assessment was conducted out to estimate the environmental impact of three coal-based electricity generation scenarios commonly used or encouraged in China, namely, sub-critical technology (300 MW), supercritical technology (600 MW), and ultra-supercritical technology (1000 MW). Compared with other scenarios, the ultra-supercritical technology accounted for significantly environmental benefits in most categories, except in the natural land occupation category because of the landfill disposal of coal ash. Optimizing net coal consumption efficiency, reusing coal ash as building material, increasing desulfurization and denitrization system efficiency, and decreasing the road transport distance from coal buyer to supplier are key factors in reducing the overall environmental impact of electricity generation. [Copyright &y& Elsevier]

Pulsed time division multiple access is recommended for psedudolite satellite signal to eliminate the near‐far effect, which is different from global navigation satellite system signal design. However, in this case, the initial frequency bias obtained from acquisition is not precise enough for the carrier tracking loop to converge due to the signal's pulse modulation, as the rolling‐off of auto‐correlation function is insensitive to slight frequency changes. This Letter proposes an approach to narrowing the initial frequency error by mapping from code Doppler to carrier Doppler, in which the former one can be obtained from a delay lock loop (DLL). Simulation results demonstrate the validity of the proposed method in the initialisation of frequency pull‐in process owing to the fixed proportion existed in the code and carrier Doppler. [ABSTRACT FROM AUTHOR]

Heavy metal contamination in soil environment is of serious concern globally with the rapid industrial development. In order to investigate the environmental risks on soil, a comprehensive study on heavy metal pollution was conducted by using 16 topsoil samples (0–20 cm) and 12 layered soil samples (0–120 cm) from Jinan Iron & Steel Group. The results show that heavy metal with the highest concentration is Zn, followed by Cr, Pb, Cu, Ni, As, Hg and Cd. The horizontal distribution pattern indicates that all metals in soil were derived from the anthropogenic activities such as coke/chemical processing and oxygen-making. The vertical distribution results show that these metals in topsoil exhibited significant accumulation. The pollution levels of metals are influenced by the temporal factor and decreased from December 2018 to April 2019. Fractionation analysis results show that Pb, Hg, Zn and Cu remained the main components in the residual fractions and their mobility potentials in soil decreased in the order of Pb > Hg > Zn > Cu. Assessment results of soil pollution level using the Nemerow composite, Geo-accumulation and Potential ecological risk indicators indicate that the studied area was contaminated with Pb (slightly), Cd (moderately) and Hg (strongly). This study helps identify the priority control components of polluted soils and provides valuable insights for decision makers to develop suitable mitigation strategies. • Enrichment of metals was found higher in the topsoil than the bottom soil. • The pollution levels of metals increased from April to December 2019. • Horizontal distribution predicted the pollution source is coke/chemical processing. • The residual fraction dominated metal distribution in soils. • Pb, Cd and Hg were the major pollutants according to the PN, Igeo and PERI indexes. [ABSTRACT FROM AUTHOR]

This paper provides a cleaner production solution for the potential usage of molybdenum tailings as a replacement of fine aggregates in structural concrete. The influence of Molybdenum tailings on the concrete properties, reinforced concrete columns and concrete-filled steel tubular columns was investigated. The environmental impact of these structural concrete products with molybdenum tailings was also assessed. The results show that the molybdenum tailings, whose radionuclides satisfy the requirement in the standard, are suitable for the preparation of structural concrete under proper replacement ratio. The workability, mechanical and duration properties of molybdenum tailing concrete are reduced by increasing the molybdenum tailings replacement ratio. The rise of replacement ratio results in a linear reduction trend on the axial strength of the reinforced concrete and concrete-filled steel tubular columns using molybdenum tailing concrete. The results of the axial compressive tests for stub columns verify the fact that molybdenum tailing concrete could be used as cleaner productions in the construction industry. The cost and environmental impact assessment indicate that concrete filled steel tube is a more preferable solution for the usage of molybdenum tailings in structural concrete, especially with higher molybdenum tailing replacement ratio. It is feasible to replace natural sand with molybdenum tailings to prepare structural concrete members along with environmental benefits. The successful application of molybdenum tailing concrete in cleaner production may further promote the sustainable development of concrete structures. • MoTC could be used as cleaner productions in construction industry. • The workability, mechanical and duration properties of MoTC are reduced by increasing MoT replacement ratio. • Axial strength of RC and CFST columns using MoTC decreases linearly with the increase of MoT replacement ratio. • CFST column is more preferable than RC column for using MoT as fine aggregate, especially with a higher replacement ratio. [ABSTRACT FROM AUTHOR]

• Combined toxicity of Pb, Cd and As remained a dose-response effect. • Co-exposure led to a lower Cd but a higher Pb and As uptake in plant. • NaCl-soluble form was predominant for Pb, Cd and As in Solanum nigrum L. • Most Pb, Cd and As were localized in the cell wall and soluble fraction for plant. • The exchangeable Cd and residual Pb/As were the predominant forms in soil. A 3-factor-5-level central composite design was conducted to investigate the combined toxicity and detoxification mechanisms of lead (Pb), cadmium (Cd) and arsenic (As) in Solanum nigrum L. The three metal(loid)s exhibited low-dose stimulation and high-dose inhibition on plant length. Analyses of eleven oxidative stress and antioxidant parameters showed all Pb, Cd and As induced oxidative damages, and the co-exposure further enhanced their toxic effects. Pb, Cd and As were mainly accumulated in plant roots and poorly translocated to shoots, being beneficial for metal(loid) detoxification. The results of subcellular fractionation showed that Pb, Cd and As in plant leaves, stems and roots were mainly localized in the cell wall and soluble fractions. Most of Pb and As in soils occurred in residual fraction while Cd in exchangeable fraction. Although single Pb, Cd and As in all plant tissues existed predominantly in 1 M NaCl-soluble form, the d-H 2 O and 80 % ethanol-soluble forms were increased under the binary or ternary combinations. This study will conduce to the potential use of S. nigrum L. in the phytostablization of soil co-contaminated with Pb, Cd and As. [ABSTRACT FROM AUTHOR]

One novel coordination polymer derived from 3,5-di(2′,5′-dicarboxylphenyl)benozoic acid (H 5 ddb) in the presence of 1,1′-benzene-1,4-diylbis(1H-imidazole) (p -bib) ancillary linker has been synthesized solvothermally, namely, {[Cd 2.5 (H 5 ddb)(p -bib)]·(p -bib) 0.5 (H 2 O) 5 } n (CP 1). Then CP 1 was characterized by single crystal X-ray diffraction analysis, IR, elemental analyses (EA), thermogravimetric analysis (TGA), and X-ray powder diffraction (PXRD). Structural analysis reveals that the host-framework of CP 1 exhibits a novel 3D (4,6)-connected net with the point symbol of {43.610.82} {43.63}. The interaction between host-framework and uncoordinated p -bib ligand as guest molecule has been discussed in detail. The solid-state luminescence property of CP 1 was tested under ultraviolet light irradiation at ambient condition. In further experiment, CP 1 showed a high selectivity and sensitivity for detecting Fe3+ cations caused by luminescence quenching effect. one novel coordination polymer have been synthesized based on the 3,5-di(2′,5′-dicarboxylphenyl)benozoic acid ligand (H 5 ddb) with the aid of bis(imodazole) linker. The host-framework of CP1 exhibits a novel 3D (4,6)-connected net with the point symbol of {43.610.82} {43.63}. The luminescent sensing of metal cations was investigated systematically. Unlabelled Image • One Novel Functional Cd-CPs as Luminescent Sensor for Efficient Sensing of Fe3+ cations in Aqueous Solution • Structural analysis reveals that the host-framework of {[Cd 2.5 (H 5 ddb)(p -bib)]·(p -bib) 0.5 (H 2 O) 5 } n exhibits a novel 3D (4,6)-connected net with the point sympol of {43.610.82} {43.63}. • {[Cd 2.5 (H 5 ddb)(p -bib)]·(p -bib) 0.5 (H 2 O) 5 } n showed a high selectivity and sensitivity for detecting Fe3+ cations caused by luminescence quenching effect. [ABSTRACT FROM AUTHOR]

Jamming and spoofing are the two main types of intentional interference for global navigation satellite system (GNSS) receivers. Due to the entirely different signal characteristics they have, a few techniques can deal with them simultaneously. This paper proposes a two-stage interference suppression scheme based on antenna arrays, which can detect and mitigate jamming and spoofing before the despreading of GNSS receivers. First, a subspace projection was adopted to eliminate the high-power jamming signals. The output signal is still a multi-dimensional vector so that the spatial processing technique can be used in the next stage. Then, the cyclostationarity of GNSS signals were fully excavated to reduce or even remove the noise component in the spatial correlation matrix. Thus, the signal subspace, including information of the power and the directions-of-arrival (DOAs) of the GNSS signals, can be obtained. Next, a novel cyclic correlation eigenvalue test (CCET) algorithm was proposed to detect the presence of a spoofing attack, and the cyclic music signal classification (Cyclic MUSIC) algorithm was employed to estimate the DOAs of all the navigation signals. Finally, this study employed a subspace projection again to eliminate the spoofing signals and provide a higher gain for authentic satellite signals through beamforming. All the operations were performed on the raw digital baseband signal so that they did not introduce additional computational complexity to the GNSS receiver. The simulation results show that the proposed scheme not only suppresses jamming and spoofing effectively but also maximizes the power of the authentic signals. Nonetheless, the estimated DOA of spoofing signals may be helpful for the interference source positioning in some applications. [ABSTRACT FROM AUTHOR]

There are much data transmitted from sensors in wireless sensor network. How to mine vital information from these large amount of data is very important for decision-making. Aiming at mining more interesting information for users, the skyline technology has attracted more attention due to its widespread use for multi-criteria decision-making. The point which is not dominated by any other points can be called skyline point. The skyline consists of all these points which are candidates for users. However, traditional skyline which consists of individual points is not suitable for combinations. To address this gap, we focus on the group skyline query and propose efficient algorithm to computing the Pareto optimal group-based skyline (G-skyline). We propose multiple query windows to compute key skyline layers, then optimize the method to compute directed skyline graph, finally introduce primary points definition and propose a fast algorithm based on it to compute G-skyline groups directly and efficiently. The experiments on the real-world sensor data set and the synthetic data set show that our algorithm performs more efficiently than the existing algorithms. [ABSTRACT FROM AUTHOR]

The exquisite combination of [Tb2(CO2)9] units and [Tb2(CO2)6(HCO2)(H2O)2]n chains under acidic solvothermal condition generated a highly robust {(Me2NH2)4[Tb4(DDAC)3(HCO2)(OH2)2]⋅6DMF⋅5H2O}n (SLU-1, H5DDAC = 2,6-di(3,5-dicarboxylphenyl)-4-aminobenzoic acid) microporous framework. In SLU-1, each four [Tb(1)2(CO2)9] units and four [Tb(2)2(CO2)6(H2O)2] units are bridged by eight DDAC5− ligands to form cage-like voids with the diameter of 8.2 Å and the moderate window size of 4.2 × 3.5 − 4.6 × 5.5 Å2. which is concurrently functionalized by amino groups on the inner surface. More interestingly, the inner surface of cage-like voids in activated SLU-1a is functionalized by free amino groups and rich unsaturated Tb3+ cations because of the dissociation of solvents. Owning to the Lewis acid–base synergistic effect derived from open metal sites, free oxygen atoms and amino groups in the confined pore environments, SLU-1 with the aid of co-catalyst n-Bu4NBr exhibited high catalytic activity on the cycloaddition of CO2 with epoxides and under mild solvent-free conditions, especially for epoxides with smaller size. A highly robust microporous framework of {(Me2NH2)4[Tb4(DDAC)3(HCO2)(OH2)2]⋅6DMF⋅5H2O}n (SLU-1) with hierarchical channels and cage-like voids exhibits the high catalytic activity on the cycloaddition reaction of CO2 with epoxides and under mild solvent-free condition. [ABSTRACT FROM AUTHOR]

A dual-channel material of {[(CH3)2NH2][Yb3(BDCP)2(H2O)3]·2DMF·3H2O}n (NUC-58) has been generated from the combination of wave-like [Yb2(CO2)6(H2O)2]n chains and [Yb(CO2)4(H2O)] units with the aid of 2,6-bis(2,4-dicarboxylphenyl)-4-(4- carboxylphenyl)pyridine, which has excellent physical and chemical properties including a larger specific surface area, high porosity, water resistance and thermal stability. NUC-58 is a rarely reported microporous MOFs with solvent-free dual channels. Thanks to its coexistence of Lewis acid–base sites including rich hexa/hepta-coordinated Yb3+ ions, C = O groups from μ1−η1:η1 CO2−, and Npyridine atoms, NUC-58 displays highly catalytic activity on the cycloaddition reaction of epoxides and CO2 into related cyclic carbonates under mild solvent-free reaction conditions. In addition, NUC-58 could be used as a fast, sensitive and highly efficiency sensor for Cu2+ detection in aqueous solution. Therefore, the work shows that microporous MOFs assembled from pyridine-containing polycarboxylic acid ligands and rare earth ions can serve as excellent catalytic and luminescent materials. A highly robust ytterbium (III)-organic framework of {[(CH3)2NH2]2[Yb3 (BDCP)2(NO3)(OH2)3]·2DMF·3H2O}n (NUC-58) for efficiently catalyzing the chemical fixation of CO2. [ABSTRACT FROM AUTHOR]

In two-way time-of-arrival (TOA) systems, a user device (UD) obtains its position and timing information by round-trip communications to a number of anchor nodes (ANs) at known locations. Compared with the one-way TOA technique, the two-way TOA scheme is easy to implement and has higher localization and synchronization accuracy. Existing two-way TOA methods assume a stationary UD. This will cause uncompensated position and timing errors. In this article, we propose an optimal maximum likelihood (ML) based two-way TOA localization and synchronization method, namely TWLAS. Different from the existing methods, it takes the UD mobility into account to compensate the error caused by the UD motion. We analyze its estimation error and derive the Cramér-Rao lower bound (CRLB). We show that the conventional two-way TOA method is a special case of the TWLAS when the UD is stationary, and the TWLAS has high estimation accuracy than the conventional one-way TOA method. We also derive the estimation error in the case of deviated UD velocity information. Numerical result demonstrates that the estimation accuracy of the new TWLAS for a moving UD reaches CRLB, better than that of the conventional one-way TOA method, and the estimation error caused by the deviated UD velocity information is consistent with the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper focuses on the carrier estimation performance improvement in Mars entry, descent, and landing (EDL) flights. Carrier reconstruction could be used for trajectory derivation and Martian atmosphere profile inversion, and is the critical information for mission operations, as it helps determine the flight status of the spacecraft, demodulate the downlink information. The current approach is maximum likelihood estimation based on a two-dimensional (2D) maximum energy search algorithm, which computes the grid energy over all the combinations of frequency cells and frequency rate cells among the search space. Although it has good performance on robust estimation, the frequency estimation accuracy is limited due to the short coherent integration. An instantaneous frequency rate tracking approach based on the cubic phase function (CPF) is proposed that directly estimates the instantaneous frequency rate over the frequency rate cells, followed by the frequency estimation among the frequency cells. A sequential estimation method is introduced to propose the sequential CPF statistics, which uses the a priori Doppler phase information to suppress the noise squaring loss inherent in the standard CPF statistics. Simulations have been made on the released Mars Science Laboratory EDL trajectory for the two approaches, which show that considerable estimation improvement has been achieved for aerobraking flight by the new algorithm. [ABSTRACT FROM AUTHOR]

Traditional Chinese Medicine (TCM) has been widely used in China and is regarded as the most important therapeutic. Polygonatum sibiricum (PS), a natural plant used in traditional Chinese medicine, has various functions associated with a number of its components. There are many compositions in PS including polysaccharides, steroids, anthraquinone, alkaloids, cardiac glycosides, lignin, vitamins, various acids, and so on. Of these, polysaccharides play a significant role in PS-based therapeutics. This article summarizes Polygonatum sibiricum polysaccharides (PSP) have many pharmacological applications and biological activities, such as their antioxidant activity, anti-aging activity, an anti-fatigue effect, immunity enhancement effect, antibacterial effect, anti-inflammatory effect, hypolipidemic and antiatherosclerotic effects, anti-osteoporosis effect, liver protection, treatment of diabetes mellitus (DM), anti-cancer effect, and may help prevent Alzheimer’s disease, and so on. This review summarized the extraction method, purification method, compositions, pharmacological applications, biological activities, biosynthesis, and prospects of PSP, providing a basis for further study of PS and PSP. [ABSTRACT FROM AUTHOR]

There are much data sampled continuously by sensors in the wireless sensor network. Storing and mining these data can find more potential information and provide help for decision making. As an important technology for data mining and multi-criteria decision, skyline computation can identify the interesting single points for user. In order to analyze the groups of points, the group-based skyline is proposed to query all the Pareto Optimal groups which are not g-dominated by other groups with the same number of points. Existing algorithms about g-skyline can just compute static data. However, data stream is very common in many applications, and it is very important to design algorithm go query g-skyline over data stream. In this paper, we propose new algorithms to compute g-skyline over a data stream. We present sharing strategy and then present two efficient algorithms: point-arriving algorithm and point-expiring algorithm. The experimental results on three kinds of synthetic data and a real stock data show that our algorithms perform efficiently over a data stream. [ABSTRACT FROM AUTHOR]

Supramolecular three ‐ dimensional polycatenanes were constructed by utilizing both of the cavity and the electropositive outer surface of cucurbit[6]uril. The infinite supramolecular 3D polycatenanes based on triply interlocked cages provide a way to construct catenanes and MOFs that have otherwise required long reaction times and tedious organic syntheses through metal coordination or covalent bonds. More information can be found in the Communication by X. ‐ L. Ni et al. on page 2759 ff. [ABSTRACT FROM AUTHOR]

Abstract Industrial sector is responsible for the majority of China's carbon dioxide (CO 2) emissions and contributed most to the rapid increment in the first decade of this century. However, CO 2 emissions in the industrial sector stagnated due to China's economic slowdown since 2012. This paper aims to estimate the CO 2 emissions in China's industrial sector during 2010–2016 to deliver sectoral and regional details and uncover the reasons for the emissions stagnancy. We find that the emission stagnancy is a result of decreasing energy intensity and economic slowdown. Industrial restructuring within the entire industrial sector and emission intensity (emissions per unit of energy consumption) had limited effect on the emissions reduction. From the sectoral perspective, iron & steel and nonmetal sectors accounted for most reduced emissions in China's industrial sectors during 2014–2016. From the regional perspective, the emissions decrease mainly occurred in western and northeastern provinces, rather than more developed coastal provinces. Mitigation policies are raised, including the industrial structure shift from energy-intensive sectors to other sectors and addressing the emissions mitigation in rapid industrializing provinces, such as Xinjiang, Inner Mongolia and Ningxia, so that an earlier and lower emission peak of China's industrial sectors can be achieved. Highlights • Iron & steel and nonmetal sectors accounted for most emissions reduction. • Decreasing energy intensity and economic slowdown are the main reasons. • Emissions in most energy-intensive sectors have peaked or approach the peak. • Emissions decrease occurred mainly in the western and northeastern provinces. [ABSTRACT FROM AUTHOR]

Anatomical adaptations to high‐salinity environments in mangrove leaves may be recorded in leaf water isotopes. Recent studies observed lower 18O enrichment (ΔL) of leaf water with respect to source water in three mangrove species relative to adjacent freshwater trees, but the factors that govern this phenomenon remain unclear. To resolve this issue, we investigated leaf traits and ΔL in 15 species of true mangrove plants, 14 species of adjacent freshwater trees, and 4 species of semi‐mangrove plants at five study sites along south‐eastern coast of China. Our results confirm that ΔL was generally 3–4‰ lower for mangrove species than for adjacent freshwater or semi‐mangrove species. We hypothesized that higher leaf water content (LWC) and lower leaf stomatal density (LS) both played important roles in reducing ΔL in mangroves relative to nearby freshwater plants. Both differences acted to elongate effective leaf mixing length (L) in mangroves by about 200% and lower stomatal conductance by about 30%. Péclet models based on both LWC and LS could accurately predict ΔL. Our findings highlight the potential species‐specific anatomical determinants of ΔL (or L), which has important implications for the interpretation of environmental information from metabolites produced by leaf water isotopes in palaeoclimate research. Mangrove forests evolve typical leaf structures to adapt to high‐salinity environments, and many of these adaptations may leave imprints in leaf water isotopes. Our comprehensive field study confirmed that the isotope enrichment of leaf water (ΔL) in mangroves were generally lower than those of the adjacent nonmangrove at multiple‐site and multiple‐species scales and that leaf anatomies play key roles in determining these differences in ΔL. The potential species‐specific anatomical determinants of ΔL based on a large pool of species can be incorporated into the leaf water model, which will have considerable potential applications not only for palaeoclimate reconstruction but also in distinguishing what kinds of plants with strong Péclet effect. [ABSTRACT FROM AUTHOR]

Along with the application of the sensor network, there will be large amount of dynamic data coming from sensors. How to dig the useful information from such data is significant. Skyline query is aiming to identify the interesting points from a large dataset. The group-based skyline query is to find the outstanding Pareto Optimal groups which cannot be g-dominated by any other groups with the group same size. However, the existing algorithms of group-based skyline (G-Skyline) focus on the static data set, how to conduct advanced research on data stream remains an open problem at large. In this paper, we propose the group-based skyline query over the data stream. In order to compute G-Skyline efficiently, we present a sharing strategy, and based on which we propose two algorithms to efficiently compute the G-Skyline over the data stream: the point-arriving algorithm and the point-expiring algorithm. In our experiments, three synthetic data sets are used to test our algorithms; the experiments results show that our algorithms perform efficiently over a data stream. [ABSTRACT FROM AUTHOR]

Simple Summary: Didymella arachidicola, the causal agent of peanut web blotch, leads to severe defoliation at the late growth stage of peanuts, and eventually to significant yield losses of up to 30%. The biology, ecology, and taxonomy of this phytopathogenic fungi have been well-studied; however, no study has focused on its genomic variation and pathogenic phenotype. Herein, we reported the first chromosome-scale genome assembly of D. arachidicola, which provides a reliable baseline for further comparative studies of plant pathogenic fungi. Combined with genome re-sequencing, we revealed the genomic variation within the D. arachidicola population, as well as comprehensively analyzed the pathogenicity-related genes to preliminarily explain their roles in forming different lesion phenotypes of peanut web blotch. This work set a genomic foundation and an adaptive landscape of D. arachidicola for understanding its genomic diversity and adaptive evolution, in parallel to the correlation of genotype and phenotype underlying the evolutionary force. Didymella arachidicola is one of the most important fungal pathogens, causing foliar disease and leading to severe yield losses of peanuts (Arachis hypogaea L.) in China. Two main lesion phenotypes of peanut web blotch have been identified as reticulation type (R type) and blotch type (B type). As no satisfactory reference genome is available, the genomic variations and pathogenicity factors of D. arachidicola remain to be revealed. In the present study, we collected 41 D. arachidicola isolates from 26 geographic locations across China (33 for R type and 8 for B type). The chromosome-scale genome of the most virulent isolate (YY187) was assembled as a reference using PacBio and Hi-C technologies. In addition, we re-sequenced 40 isolates from different sampling sites. Genome-wide alignments showed high similarity among the genomic sequences from the 40 isolates, with an average mapping rate of 97.38%. An average of 3242 SNPs and 315 InDels were identified in the genomic variation analysis, which revealed an intraspecific polymorphism in D. arachidicola. The comparative analysis of the most and least virulent isolates generated an integrated gene set containing 512 differential genes. Moreover, 225 genes individually or simultaneously harbored hits in CAZy-base, PHI-base, DFVF, etc. Compared with the R type reference, the differential gene sets from all B type isolates identified 13 shared genes potentially related to lesion phenotype. Our results reveal the intraspecific genomic variation of D. arachidicola isolates and pathogenicity factors potentially related to different lesion phenotypes. This work sets a genomic foundation for understanding the mechanisms behind genomic diversity driving different pathogenic phenotypes of D. arachidicola. [ABSTRACT FROM AUTHOR]

The sine-BOC (binary offset carrier) modulation is used in several signals of the new European Global Navigation Satellite System, Galileo, and modernized GPS. It provides these signals with enhanced robustness against multipath and increases the precision of the range measurement. However, this modulation presents some drawbacks. The most severe is the ambiguity problem in acquisition and tracking, which introduces a large bias in the pseudo-range measurement. In order to solve this problem, an unambiguous tracking technique for sine-BOC signals is proposed. This technique is based on a pseudo correlation function (PCF) which does not have any side peak and thus completely removes all of the false lock points on the discriminator output. Impacts of thermal noise and multipath on the proposed technique are investigated. Theoretical and numerical results obtained with BOC(n,n) and BOC(2n,n) signals show that this technique has a good noise mitigation performance and an average multipath performance. [ABSTRACT FROM PUBLISHER]

This study aimed to explore the co-removal effect and mechanism of Cr(VI) and Cd(II) with an optimized synthetic material. The toxicity and accumulation characteristics of Cr(VI) and Cd(II) encountered in wastewater treatment areas present significant challenges. In this work, a rational assembly of sulfide-modified nanoscale zero-valent iron (SnZVI) was introduced into a biochar (BC), and a Cr(VI)–Cd(II) binary system adsorbent with high efficiency was synthesized. When the preparation temperature of the BC was 600 °C, the molar ratio of S/Fe was 0.3, the mass ratio of BC/SnZVI was 1, and the best adsorption capacities of BC-SnZVI for Cr(VI) and Cd(II) in the binary system were 58.87 mg/g and 32.55 mg/g, respectively. In addition, the adsorption mechanism of BC-SnZVI on the Cr(VI)-Cd(II) binary system was revealed in depth by co-removal experiments, indicating that the coexistence of Cd(II) could promote the removal of Cr(VI) by 9.20%, while the coexistence of Cr(VI) could inhibit the removal of Cd(II) by 43.47%. This work provides a new pathway for the adsorption of Cr(VI) and Cd(II) in binary systems, suggesting that BC-SnZVI shows great potential for the co-removal of Cr(VI) and Cd(II) in wastewater. [ABSTRACT FROM AUTHOR]

Performance analysis of Global Navigation Satellite Systems (GNSS) collaborative positioning accuracy is a challenging task since there are too many impact factors. To simplify the analysis, the collaborative dilution of precision (CDOP) model is proposed to specify the multiplicative effect of various factors on the accuracy of collaborative positioning. Based on this CDOP model, the theoretical analysis and simulation tests are performed, and the results are compared with GNSS standalone positioning. The impacts of the number of users and their distribution and of relative distance measurement accuracy are also analyzed and verified under this CDOP model. Experiments are carried out with several real-time GNSS receivers in actual outdoor and partially blockage scenarios, respectively, and the results are consistent with theoretical analysis. [ABSTRACT FROM AUTHOR]

It is an essential technique for the moving user nodes (UNs) with clock offset and clock skew to resolve the joint localization and synchronization (JLAS) problem. Existing iterative maximum likelihood methods using sequential one-way time-of-arrival (TOA) measurements from the anchor nodes’ (AN) broadcast signals require a good initial guess and have a computational complexity that grows with the number of iterations, given the size of the problem. In this paper, we propose a new closed-form JLAS approach, namely CFJLAS, which achieves the asymptotically optimal solution in one shot without initialization when the noise is small, and has a low computational complexity. After squaring and differencing the sequential TOA measurement equations, we devise two intermediate variables to reparameterize the non-linear problem, and convert it to a simpler one of solving two simultaneous quadratic equations. We then solve the equations analytically to obtain a raw closed-form JLAS estimation. Finally, we apply a weighted least squares (WLS) step to optimize the estimation. We derive the Cramér-Rao lower bound (CRLB), analyze the estimation error, and show that the estimation accuracy of the CFJLAS reaches the CRLB under the small noise condition. The complexity of the new CFJLAS is only determined by the size of the problem, unlike the conventional iterative method, whose complexity is additionally multiplied by the number of iterations. Simulations in a 2D scene verify that the estimation accuracies of the new CFJLAS method all reach the CRLB under the small noise condition. Compared with the conventional iterative method, the proposed new CFJLAS method does not require initialization, obtains the optimal solution under the small noise condition, and has a low computational complexity. [ABSTRACT FROM AUTHOR]

As the modern navigation business evolves, demands for high-precision positioning in GNSS-challenged environments increase, and the integrated system composed of Global Navigation Satellite System (GNSS)-based Real-Time Kinematic (RTK), inertial system (INS), Light Detection and Ranging (LiDAR), etc., is accepted as the most feasible solution to the issue. For prior-map-free situations, as the only sensor with a global frame, RTK determines and maintains the global positioning precision of the integrated system. However, RTK performance degrades greatly in GNSS-challenged environments, and most of the existing integrated systems adopt loose coupling mode, which does nothing to improve RTK and, thus, prevents integrated systems from further improvement. Aiming at improving RTK performance in the RTK/LiDAR/INS integrated system, we proposed an innovative integrated algorithm that utilizes RTK to register LiDAR features while integrating the pre-registered LiDAR features to RTK and adopts parallel filters in the ambiguity-position-joint domain to weaken the effects of low satellite availability, cycle slips, and multipath. By doing so, we can improve the RTK fix rate and stability in GNSS-challenged environments. The results of the theoretical analyses, simulation experiments, and a road test proved that the proposed method improved RTK performance in GNSS-challenged environments and, thus, guaranteed the global positioning precision of the whole system. [ABSTRACT FROM AUTHOR]

Summary: The cellulose paper-based functional materials modified by Zn-NDI and Cu-NDI were prepared by the coating method. The chemical structures were characterized by FTIR, XRD, UV-vis and SEM, and the photochromic properties of the composite functional materials wer e studied. The results showed that Zn-NDI and Cu-NDI were successfully prepared and retained on the surface of copy paper, the wavelength of photochromic reaction is between 300-400 nm of MOFs materials. Optical analysis confirmed that the NDI/paper, Zn-NDI/paper and Cu-NDI/paper changed from tan to wheat, light green to olive, and dark tan to brown after 60 seconds of exposure to hernia light irradiations, the MOFs coated paper returned to its original color when it was placed in the dark for 4 hours. The above results indicated that the prepared Zn-NDI and Cu-NDI coated paper composites exhibited excellent photochromic ability and had potential applications in the field of anti-counterfeiting packaging materials. [ABSTRACT FROM AUTHOR]

Background: Although great efforts have been made to quantify mangrove carbon stocks, accurate estimations of below-ground carbon stocks remain unreliable. In this study, we examined the distribution patterns of mangrove carbon stocks in China and other countries using our own field survey data and datasets from published literature. Based on these data, we investigated the possible relationships between above-ground carbon stock (AGC) and below-ground carbon stock (BGC) for mangrove forests, aiming to provide a scientific basis for estimation of total mangrove carbon stocks. Results: The average above-ground carbon stock in each region was sizeable (ranging from 12.0 to 150.2 Mg/ha), but average below-ground carbon stock was dominant (ranging from 46.6 to 388.6 Mg/ha), accounting for 69–91% of total carbon stock at the sites studied in China. Significant positive relationships were found between above-ground and below-ground mangrove carbon stocks, with the best fitting equation as BGC = 1.58 * AGC + 81.06 (Mg/ha, R2 = 0.62, p < 0.01, n = 122) for China. Such linear relationships vary for mangrove forests of different types and locations, from different geographical regions in China to other countries worldwide. Conclusion: The positive relationship we found between above- and below-ground carbon stocks of mangrove forests in China and worldwide can facilitate more accurate assessments of mangrove blue carbon stocks at regional or global scales using modern techniques including remote sensing. [ABSTRACT FROM AUTHOR]

• CO 2 and H 2 O fluxes were measured in a subtropical mangrove forest over the decade. • This mangrove forest acted as a strong CO 2 sink during the study period. • Global solar radiation and VPD primarily drove the mangrove NEP in the dry season. • Meteorological and tidal factors jointly controlled the NEP in the wet season. • The importance of certain climate conditions on NEP and ET changed over ten years. Mangroves, highly efficient ecosystems in sequestering CO 2 , are strongly impacted by climate change. The lack of long-term observation in mangroves hinders the evaluation of seasonal and inter-annual variability in carbon and water fluxes and their responses to various environmental drivers. In this study, we measured net ecosystem CO 2 exchange and evapotranspiration between the atmosphere and subtropical mangroves using the eddy covariance technique over a decade (2010–2019) in southern China. This mangrove forest acted as a strong CO 2 sink, with annual net ecosystem production (NEP) ranging from 622.5 to 832.8 g C m−2 year−1. The annual evapotranspiration (ET) varied between 934.6 and 1004.9 mm year−1. During the study period, ET consistently remained higher in the wet season (May to October) compared to the dry season, while NEP did not exhibit consistent seasonal variation. Path analysis indicated that during the dry season, NEP was primarily influenced by global solar radiation and vapor pressure deficit. However, in the wet season, NEP was regulated by a combination of global solar radiation, vapor pressure deficit, air temperature, and tidal inundation time. Additionally, the promoting effect of global solar radiation on NEP decreased in the wet season, while the inhibitory influences of higher temperature and vapor pressure deficit on NEP intensified during the period. Unlike NEP, the dominant factors affecting ET (global solar radiation, air temperature, and vapor pressure deficit) and their intensities remained relatively consistent during both seasons. Furthermore, the relative importance of global solar radiation on NEP and ET increased over the decade, while the influence of tidal inundation time diminished. This study not only improves the understanding of the response of subtropical mangroves to climate change but also provides a valuable benchmark dataset to validate the interannual variability of mangrove carbon and water fluxes estimated from the models. [ABSTRACT FROM AUTHOR]

Radio-based positioning systems are typically utilized to provide high-precision position information for automatic-guided vehicles (AGVs). However, the presence of obstacles in harsh environments, as well as carried cargoes on the AGV, will degrade the localization performance, since they block the propagation of radio signals. In this paper, a distributed multi-antenna positioning system is proposed, where multiple synchronous antennas are equipped on corners of an AGV to improve the availability and accuracy of positioning. An estimator based on the Levenberg–Marquardt algorithm is introduced to solve the nonlinear pseudo-range equations. To obtain the global optimal solutions, we propose a coarse estimator that utilizes the displacement knowledge of the antennas to provide a rough initial guess. Simulation results show a better availability of our system compared with the single antenna positioning system. Decimeter accuracy can be obtained under a Gaussian measurement noise with a standard deviation of 0.2 m. The results also demonstrate that the proposed algorithm can achieve positioning accuracy close to the theoretical Cramer–Rao lower bound. Furthermore, given prior information of the yaw angle, the same level of accuracy can be obtained by the proposed algorithm without the coarse estimation step. [ABSTRACT FROM AUTHOR]

• We examined effects of a bud moth larvae outbreak on mangrove growth and reproduction. • The BML outbreak damaged 90% of the foliage and increased leaf litterfall production. • NEP decreased following the BML outbreak and recovered within several months. • Flower production largely decreased and there was nearly no propagule production. • The BML outbreak had asymmetric effects on vegetative and reproductive growth. Mangroves are experiencing frequent severe insect outbreaks, and the bud moth larvae (BML; Lasiognatha cellifera) is one of the most common leaf-feeding insects. However, the effects of insect outbreaks on ecosystem carbon fluxes of mangrove ecosystems are not well understood, and more importantly, the relative effects of these disturbances on vegetative and reproductive growth of mangroves remain unclear. We used measurements of plant litterfall, leaf damage percentage, and insect frass production, satellite-derived normalized difference vegetation index (NDVI), and eddy covariance flux measurements to quantify the impacts of a BML outbreak in 2010 on carbon fluxes and both vegetative and reproductive growth of a mangrove forest. The BML outbreak occurred in 2010 damaged nearly 90% of the foliage, increased the annual leaf litterfall, and decreased the flower and propagule production. Net ecosystem productivity decreased following the insect disturbance and recovered within several months. There were no significant differences in annual carbon fluxes among the four years from 2009 to 2013. In contrast, the flower production significantly decreased and there was nearly no propagule production after the insect outbreak. Reproductive growth did not recover even two years after the insect outbreak. Our results showed that the BML outbreak had asymmetric effects on vegetative and reproductive growth of mangrove forests. Our findings can help us better understand the impacts of insect disturbances on mangrove ecosystems and also have implications for informing mangrove conservation and restoration efforts. [ABSTRACT FROM AUTHOR]

Robust and centimeter-level Real-time Kinematic (RTK)-based Global Navigation Satellite System (GNSS) positioning is of paramount importance for emerging GNSS applications, such as drones and automobile systems. However, the performance of conventional single-rover RTK degrades greatly in urban environments due to signal blockage and strong multipath. The increasing use of multiple-antenna/rover configurations for attitude determination in the above precise positioning applications, just as well, allows more information involved to improve RTK positioning performance in urban areas. This paper proposes a dual-antenna constraint RTK algorithm, which combines GNSS measurements of both antennas by making use of the geometric constraint between them. By doing this, the reception diversity between two antennas can be taken advantage of to improve the availability and geometric distribution of GNSS satellites, and what is more, the redundant measurements from a second antenna help to weaken the multipath effect on the first antenna. Particularly, an Ambiguity Dilution of Precision (ADOP)-based analysis is carried out to explore the intrinsic model strength for ambiguity resolution (AR) with different kinds of constraints. Based on the results, a Dual-Antenna with baseline VEctor Constraint algorithm (RTK) is developed. The primary advantages of the reported method include: (1) Improved availability and success rate of RTK, even if neither of the two single-antenna receivers can successfully solve the AR problem; and (2) reduced computational burden by adopting the concept of measurement projection. Simulated and real data experiments are performed to demonstrate robustness and precision of the algorithm in GNSS-challenged environments. [ABSTRACT FROM AUTHOR]

Functional, noncoding RNA of about 200 nucleotides in length are known as long noncoding RNA (lncRNA). Advances in ‐omics have revolutionized the information with respect to the coding and noncoding regions of the genome. Several studies have illustrated the role of lncRNA in cell growth and cancer. Profiling and bioinformatic studies of laryngeal cancer has identified LINC‐PINT as one of the lncRNA. However, the functional aspects of the deregulation have not been studied in laryngeal tumors. In this study, LINC‐PINT expression in normal and tumor tissues were studied. Using a bioinformatic approach, microRNA (miRNA) targets of LINC‐PINT and gene targets of the miRNA were determined. The impact of LINC‐PINT on cell proliferation and chemoresistance was determined. Further through a set of silencing and re‐expression studies phenotype rescue was studied. LINC‐PINT expression was downregulated in laryngeal tumors. LINC‐PINT targeted miR‐425‐5p by three sites. miR‐425‐5p also targeted PTCH1 a protein of the Hedgehog pathway. Downregulation of LINC‐PINT was associated with increased cancer stemness and chemoresistance to cisplatin. Our results indicate a probable role of LINC‐PINT in the pathology of laryngeal tumors. LINC‐PINT re‐expression in laryngeal tumors may be explored for reversion of cancer cell stemness and also for rescue of drug resistance phenotype. [ABSTRACT FROM AUTHOR]