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The nuclear pore complex (NPC) has multiple functions beyond the nucleo-cytoplasmic transport of large molecules. Subnuclear compartmentalization of chromatin is critical for gene expression in animals and yeast. However, the mechanism by which the NPC regulates gene expression is poorly understood in plants. Here we report that the Y-complex (Nup107–160 complex, a subcomplex of the NPC) self-maintains its nucleoporin homeostasis and modulates FLOWERING LOCUS C (FLC) transcription via changing histone modifications at this locus. We show that Y-complex nucleoporins are intimately associated with FLC chromatin through their interactions with histone H2A at the nuclear membrane. Fluorescence in situ hybridization assays revealed that Nup96, a Y-complex nucleoporin, enhances FLC positioning at the nuclear periphery. Nup96 interacted with HISTONE DEACETYLASE 6 (HDA6), a key repressor of FLC expression via histone modification, at the nuclear membrane to attenuate HDA6-catalyzed deposition at the FLC locus and change histone modifications. Moreover, we demonstrate that Y-complex nucleoporins interact with RNA polymerase II to increase its occupancy at the FLC locus, facilitating transcription. Collectively, our findings identify an attractive mechanism for the Y-complex in regulating FLC expression via tethering the locus at the nuclear periphery and altering its histone modification. The nuclear pore Y-complex acts as a functional compartmentalization platform for histone epigenetic modification at the FLOWERING LOCUS C locus conferring flowering regulation in Arabidopsis. [ABSTRACT FROM AUTHOR]

The stable genetic transformation of soybean is time-consuming and inefficient. As a simple and practical alternative method, hairy root transformation mediated by Agrobacterium rhizogenes is widely applied in studying root-specific processes, nodulation, biochemical and molecular functions of genes of interest, gene editing efficiency of CRISPR/Cas9, and biological reactors and producers. Therefore, many laboratories have developed unique protocols to obtain hairy roots in composite plants composed of transgenic roots and wild-type shoots. However, these protocols still suffer from the shortcomings of low efficiency and time, space, and cost consumption. To address this issue, we developed a new protocol efficient regeneration and transformation of hairy roots (eR&T) in soybean, by integrating and optimizing the main current methods to achieve high efficiency in both hairy root regeneration and transformation within a shorter period and using less space. By this eR&T method, we obtained 100% regeneration of hairy roots for all explants, with an average 63.7% of transformation frequency, which promoted the simultaneous and comparative analysis of the function of several genes. The eR&T was experimentally verified Promoter:GUS reporters, protein subcellular localization, and CRISPR/Cas9 gene editing experiments. Employing this approach, we identified several novel potential regulators of nodulation, and nucleoporins of the Nup107-160 sub-complex, which showed development-dependent and tissue-dependent expression patterns, indicating their important roles in nodulation in soybean. Thus, the new eR&T method is an efficient and economical approach for investigating not only root and nodule biology, but also gene function. [ABSTRACT FROM AUTHOR]

When a missile-borne radar system works in downward-looking surveillance mode, the broadened ground clutter signal in virtue of platform high-speed motion will be received by the radar receiver, which will cause difficulty in moving target detection and attacking. Unlike airborne and spaceborne platforms, a missile-borne platform exhibits some unique motion characteristics, such as diving, spinning, and coning, causing the clutter space–time distribution property significantly different from those of airborne and spaceborne radar platforms. In addition, the forward target striking requirements make the missile-borne clutter space–time spectrum further exhibit the severe range-dependent property. To deal with these issues, accurate motion modeling of a missile-borne radar platform is first carried out in this article, where the complex platform motions including forward-looking diving, spinning, and coning are considered. Then, the autocorrelation processing combined with iterative adaptive approach is applied to estimate the clutter angle-Doppler center frequencies, so as to effectively realize the clutter nonstationary compensation along spatial and temporal directions. Finally, a time-domain sliding window-based subspace projection method is proposed to achieve the robust clutter suppression. Both simulation and real-measured radar data processing results are presented to validate the effectiveness and feasibility of the proposed algorithm. [ABSTRACT FROM AUTHOR]

When an early warning radar installed in a spaceborne platform works in a down-looking mode to detect a low-altitude flying target, the severely broadened main-lobe clutter cannot be ignored, which will cause the deterioration of the moving target detection capability. To deal with this problem, a space–time adaptive processing (STAP) technique is proposed for effective clutter suppression based on the spatial–temporal 2-D joint filtering. However, the full-dimensional optimal STAP encounters the challenges of high computational complexity and large training sample requirement. Therefore, the dimension-reduced STAP technique becomes necessary. This article proposes a novel dimension-reduced STAP algorithm based on spatial–temporal 2-D sliding window processing. First, several sets of spatial–temporal data are obtained by using spatial–temporal 2-D sliding window. Then, for each set of data, the 2-D discrete Fourier transform is performed to transform the echo data into the angle-Doppler domain. Finally, jointly adaptive processing is performed to realize the clutter suppression. Compared with the conventional STAP algorithms, the improvements of this method over the existing methods are: 1) the proposed method requires fewer training samples due to the 2-D localization processing and 2) the proposed method can obtain the better clutter suppression performance with lower computational complexity. The feasibility and effectiveness of the proposed algorithm are verified by both simulated and real-measured multichannel surveillance radar data. [ABSTRACT FROM AUTHOR]

In inverse synthetic aperture radar (ISAR) imaging for a uniformly moving rigid-body target, a finely focused ISAR image can be obtained by using the conventional range-Doppler algorithm. However, the ISAR image quality may significantly deteriorate when the time-vary Doppler phases in virtue of target maneuvering motions are present, such as an airplane with nonuniformly rotation and a ship with fluctuation. This has become a challenging task, especially under nonhigh signal-to-noise ratio (SNR) environment. In this article, a novel ISAR imaging algorithm for a maneuvering target with moderate reflection intensity is proposed. After motion compensation, the radar echo signal in a range cell is modeled as a multicomponent cubic phase signal (CPS), in which the chirp rate and the quadratic chirp rate are two important physical quantities that may determine the target ISAR focusing quality. Based on a symmetrical instantaneous autocorrelation function, the received CPSs are transformed into the time and lag-time plane, and then a 2-D coherent integration can be realized after the generalized time-scaled transform and 1-D maximization. This forms a high-quality ISAR image. The effectiveness and superiority of the proposed algorithm are validated by the ISAR imaging results of simulated and real measured data. [ABSTRACT FROM AUTHOR]

In this article, we propose a multichannel sea clutter model in a spaceborne early warning radar system and analyze the influence of the sea clutter motion characteristics on the space-time adaptive processing (STAP) performance. To establish a multichannel sea clutter model, the 3-D Gerstner wave model is applied to construct the sea surface. Then the Pierson–Moskowitz wave spectrum and the stereo wave observation project (SWOP) directional spectrum are combined to describe the amplitude distribution of waves in different frequencies and directions. At the same time, the two-scale model is applied to obtain the specific backscattering coefficients of sea clutter at different time and positions. In addition, breaking waves are added in sea clutter returns with the form of false targets. Finally, the space-time distribution characteristics of sea clutter in a spaceborne multichannel array system and the influences of sea clutter under different wind speeds and directions on STAP performance are analyzed based on the simulation processing results. Processing results of some real-measured radar data are also exhibited to verify the theoretical analyses. [ABSTRACT FROM AUTHOR]

In this paper, a new algorithm is presented to image ground moving targets in a synthetic aperture radar (SAR) system based on range frequency reversal transform-fractional Fourier transform (RFRT-FrFT). In this algorithm, a range compressed signal is initially transformed into the range frequency domain and then RFRT is proposed to directly compensate the range migration via multiplying the signal in the range frequency domain by its reversed data according to the equal interval sampling of range frequency variable, which can significantly decrease the computational complexity in target envelope migration elimination. Then, FrFT is applied to accomplish the target motion parameter estimation after range migration alignment. Finally, a ground moving target is well focused after motion compensation. The effectiveness of the proposed algorithm is validated by both simulated and real SAR data. [ABSTRACT FROM AUTHOR]

In this paper, we propose a long-time coherent integration method for a maneuvering target with the first-, second-, and third-order range migrations, and the complex Doppler frequency migration. In this method, after range compression, the echo signal is first transformed into the range-frequency and Doppler domain based on series reversion, and then an azimuth matched filtering procedure is implemented in the 2-D frequency domain. It can eliminate the coupling effects between range and azimuth jointly caused by the radial velocity, radial acceleration, and radial acceleration rate of a moving target. Due to the linear transform property, the proposed method can work well under low signal-to-clutter and noise ratio. In addition, the Doppler ambiguities, when target azimuth spectrum either is within a pulse repetition frequency (PRF) or spans over neighboring PRF bands, can be well solved. Both simulated and real synthetic aperture radar data processing results are provided to validate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In synthetic aperture radar (SAR), long integration time may induce range migration and Doppler frequency migration of a received signal, which may degrade the SAR imaging performance of ground moving targets. Most of the conventional algorithms deal with the problems of range migration and Doppler frequency migration based on parameter searching. However, the exhaustive searching of target motion parameters may result in heavy computational burden. To avoid this problem, this paper proposes a new imaging method for ground moving targets without target motion parameter estimation. First, Keystone transform is applied to correct the range walk. Second, range curvature is compensated by the matched filtering function. Third, Doppler frequency migration is compensated via multiplying the data in range- and azimuth-time domains by its reversed conjugate data according to the equal interval sampling of the azimuth slow time, which avoids the searching procedure for target motion parameter estimation. Finally, the signal energy will be well accumulated in the range–Doppler domain, and thus, the moving targets can be efficiently recognized in the focused image. The major advantage of the proposed method is that it can obtain well-focused images of all targets in one processing step without target motion parameter estimation; thus, it is computationally efficient. Both simulated and real data processing results are used to validate the effectiveness of the proposed method. [ABSTRACT FROM PUBLISHER]

This paper proposes a new method to focus a ground moving target with complex motions and estimate its motion parameters in a synthetic aperture radar (SAR) system. In this method, the second-order Keystone transform is applied to correct the range curvature. Then, the Hough transform is applied to estimate the slope of the range walk trajectory, from which the target cross-track velocity is obtained. Finally, a generalized Hough-high-order ambiguity function (GHHAF) transform is applied to transform the target signal into a 2-D time–frequency plane and estimate its slope associated with the third-order Doppler parameter. Compared with the conventional SAR imaging methods using the second-order phase model, the proposed method can obtain better imaging quality since the third-order Doppler frequency migration is effectively eliminated. Both simulated and real data processing results are provided to validate the effectiveness of the proposed algorithm. [ABSTRACT FROM PUBLISHER]

The effects of complicated motion error on synthetic aperture radar have been analysed. A precise frequency‐division is proposed based on the precise angle‐frequency relation. The proposed method completely compensates the residual aperture‐variant motion and can be integrated into the traditional image formation algorithms directly. Both the simulated data and real airborne data have been applied to validate this method. [ABSTRACT FROM AUTHOR]

In synthetic aperture radar (SAR) imaging of a ground moving target, long-time coherent integration may effectively improve the imaging quality, whereas the imaging performance may severely degrade due to the range migration and the Doppler frequency migration. In this paper, a novel motion parameter estimation method named second-order Wigner–Ville distribution (SoWVD) transform is proposed, and then, a new SAR imaging method based on the SoWVD for a ground moving target is developed. As a modified Wigner–Ville distribution method, the SoWVD method can estimate the motion parameter without the search procedure, which achieves motion parameter estimation by Fourier transform operations in the 2-D frequency plane with respect to the slow time and the delay time. In addition, it can effectively recognize the cross terms based on multiple symmetrical properties of the peaks in the 2-D frequency domain. Both simulated and real data processing results are presented to validate the proposed imaging method. [ABSTRACT FROM PUBLISHER]

Ferrous sulfate waste has become a bottleneck in the sustainable development of the titanium dioxide industry in China. In this study, we propose a new method for the reductive decomposition of ferrous sulfate waste using pyrite. Thermodynamics analysis, tubular reactor experiments, and kinetics analysis were performed to analyze the reaction process. The results of the thermodynamic simulation showed that the reaction process and products were different when molar ratio of FeSO 4 /FeS 2 was changed. The suitable molar ratio of FeSO 4 /FeS 2 was 8–12. The reaction temperature of ferrous sulfate with pyrite was 580–770 K and the main products were Fe 3 O 4 and SO 2 . The simulation results agreed well with the experimental results. The desulphurization rate reached 98.55% and main solid products were Fe 3 O 4 at 823.15 K when mole ratio of FeSO 4 /FeS 2 was 8. Nano-sized magnetite was obtained at this condition. The kinetic model was investigated by isoconversional methods. The average E value was 244.34 kJ mol −1 . The ferrous sulfate decomposition process can be treated as autocatalytic reaction mechanism, which corresponded to the expanded Prout–Tompson (Bna) model. The reaction mechanism of autocatalytic reactions during the process of ferrous sulfate decomposition were explored, the products of Fe oxide substances are the catalyst components. [ABSTRACT FROM AUTHOR]

This Letter addresses the coherent integration problem for air and space moving target detection in a staggered pulse repetition interval (PRI) radar system. In this algorithm, a range‐compressed signal is firstly transformed into the one in the range frequency domain, and then the authors resample the non‐uniformly sampled signal into a uniform grid along azimuth direction. Subsequently, the well‐known Keystone transform is applied to compensate the range cell migration caused by target motion. Finally, a moving target can be well focused in the range‐Doppler domain after motion compensation. Simulated results are provided to validate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Many methods have been used to treat ferrous sulfate, but the large volume of waste ferrous sulfate produced has become a bottleneck for the sustainable development of the titanium dioxide industry in China. However, a newly developed process can utilize the massive volumes of waste, thereby facilitating the sulfur cycle and the recycling of iron resources, where the ferric sulfate obtained from ferrous sulfate by oxidation is decomposed reductively by pyrite, and the decomposition products are magnetite and sulfur dioxide. The reductive decomposition of ferric sulfate by pyrite is a key step in this process. In this study, thermodynamic analysis, tubular reactor experiments, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy were used to analyze the mechanism and to determine the kinetic model of the decomposition reaction in a nitrogen atmosphere. The results of the reaction mechanism analysis showed that the process involved in the generation of FeO is a two-step reaction, i.e., pyrite reacts directly with ferric sulfate to produce FeO, before FeO reacts with pyrite to generate FeO. Accordingly, the results of the kinetic analysis indicated that the first process follows an n-th order model with autocatalysis ( C), n = 1.344; and the second process follows the Avrami-Erofe'ev nuclei growth model ( A), n = 0.520. [ABSTRACT FROM AUTHOR]

Due to the advantages of wide coverage, continuous remote monitoring, and high measurement accuracy, the spaceborne multi‐channel surveillance radar has been widely used for the air moving target detection and tracking. In this paper, the minimum detection velocity (MDV) definition for the aerial target detection performance evaluation in a spaceborne multi‐channel radar system is analysed, where three kinds of MDV definitions based on empirical formula, output signal‐to‐clutter‐plus‐noise ratio (SCNR) loss criterion, and output SCNR criterion are discussed in detail based on theoretical analysis and simulation verification. The analysis results will provide valuable reference for the practical spaceborne radar system designment with the air target detection mode. [ABSTRACT FROM AUTHOR]

Soybean-seed development is controlled in multiple ways, as in many known regulating genes. Here, we identify a novel gene, Novel Seed Size (NSS), involved in seed development, by analyzing a T-DNA mutant (S006). The S006 mutant is a random mutant of the GmFTL4pro:GUS transgenic line, with phenotypes with small and brown seed coats. An analysis of the metabolomics and transcriptome combined with RT-qPCR in the S006 seeds revealed that the brown coat may result from the increased expression of chalcone synthase 7/8 genes, while the down-regulated expression of NSS leads to small seed size. The seed phenotypes and a microscopic observation of the seed-coat integument cells in a CRISPR/Cas9-edited mutant nss1 confirmed that the NSS gene conferred small phenotypes of the S006 seeds. As mentioned in an annotation on the Phytozome website, NSS encodes a potential DNA helicase RuvA subunit, and no such genes were previously reported to be involved in seed development. Therefore, we identify a novel gene in a new pathway controlling seed development in soybeans. [ABSTRACT FROM AUTHOR]

The spaceborne high-resolution and wide-swath synthetic aperture radar (HRWS-SAR) system combined with the ground moving target indication (GMTI) mode provides a promising prospect in the realization of wide-area target surveying and high-resolution target imaging. In this paper, a system design method is proposed for an HRWS-SAR-GMTI system with ideal reconstruction configuration. In the proposed method, the whole azimuth receiving channels are uniformly divided into multiple groups, where HRWS-SAR imaging is implemented in each sub-group and then GMTI processing is performed based on the reconstructed SAR images. Then, an optimal candidate PRF is properly selected with respect to the optimal reconstruction configuration. After that, the digital beam forming scanning on receive (DBF-SCORE) technique is applied to further enlarge the range swath and improve the noise equivalent scattering coefficient (NESZ). Based on the predesigned system, HRWS-SAR image-based GMTI processing can finally be accomplished. The effectiveness of the proposed method is validated by simulated experiments. [ABSTRACT FROM AUTHOR]

The article studies granitic magmatism in late Paleozoic tectonic magmatic metallogenic belt. The study collected 33 samples from 11 granitoid plutons in the Hatu and Bieluagaxi areas and created tectonic environments of the West Junggar granitoids in China through chemical analyses and isotopic tracing. It also compared West Junggar granitoids with the granitoids in the Balkhash metallogenic belt, Kazakhstan.

The article discusses research on Granitic Magmatism in the West Junggar Metallogenic Belt (Xinjiang), Central Asia in late Paleozoic period and its tectonic implication. Topics discussed include interaction between the crust and the mantle of continental crustal growth and evolution; determination of the tectonic environments of the West Junggar granitoids via chemical analyses and isotopic tracing; and study of granites, tectonic environment of Late Paleozoic in West Junggar.

Background: Starch is synthesized during daylight for temporary storage in leaves and then degraded during the subsequent night to support plant growth and development. Impairment of starch degradation leads to stunted growth, even senescence and death. The nuclear pore complex is involved in many cellular processes, but its relationship with starch degradation has been unclear until now. We previously identified that two Nucleoporin98 genes (Nup98a and Nup98b) redundantly regulate flowering via the CONSTANS (CO)-independent pathway in Arabidopsis thaliana. The double mutant also shows severe senescence phenotypes. Results: We find that Nucleoporin 98 participates in the regulation of sugar metabolism in leaves and is also involved in senescence regulation in Arabidopsis. We show that Nup98a and Nup98b function redundantly at different stages of starch degradation. The nup98a-1 nup98b-1 double mutant accumulates more starch, showing a severe early senescence phenotype compared to wild type plants. The expression of marker genes related to starch degradation is impaired in the nup98a-1 nup98b-1 double mutant, and marker genes of carbon starvation and senescence express their products earlier and in higher abundance than in wild type plants, suggesting that abnormalities in energy metabolism are the main cause of senescence in the double mutant. Addition of sucrose to the growth medium rescues early senescence phenotypes of the nup98a-1 nup98b-1 mutant. Conclusions: Our results provide evidence for a novel role of the nuclear pore complex in energy metabolism related to growth and development, in which Nup98 functions in starch degradation to control growth regulation in Arabidopsis. [ABSTRACT FROM AUTHOR]

Much research from open literature shows that polarization diversity can provide another dimension which may be exploited to improve the performance in ground moving target indication (GMTI), compared with space–time adaptive processing (STAP). In this article, we report the multichannel synthetic aperture radar (SAR)-based GMTI (SAR-GMTI) experiment and its preliminary results with a N-SAR system which is an airborne quadrature-polarimetric (quad-pol) radar system. First, the joint polarization-space adaptive processing (JPolSAP) is performed in the image level, but two suboptimal versions of JPolSAP, where the polarimetric matched filter (PMF) vector and the full-one vector are exploited to substitute for the polarimetric steering vector, respectively, are evaluated since the polarimetric steering vector of the moving target is unknown precisely in practical applications. Then, considering the computational complexity and lack of secondary data in a inhomogeneous environment due to high degrees of freedom of the JPolSAP processor, two cascade processors are evaluated, including the polarization enhancement that uses PMF and noncoherence integration detection (NCID) technique. Furthermore, we utilize the polarization information to accomplish SAR terrain classification, and subsequently secondary data from the same scattering type clutter can be obtained for clutter suppression under the guidance of polarization classification results as a priori knowledge. Finally, the experimental results demonstrate that: 1) the suboptimal JPolSAP processor with PMF steering vector can effectively enhance GMTI performance about 13 dB (or even up to 5 dB) relative to the worst (or best) single-polarization (S-pol) processor case and has the best robustness compared with the one with full-one steering vector; 2) polarization enhancement using PMF also obtains a good output gain of polarization filter, especially for quad-pol enhancement, which gains up to 2–3 dB with respect to the best output of S-pol processor, and the NCID technique can obtain good performance of moving-target detection; and 3) under the guidance of polarization classification results, the capability of clutter suppression can improve even up to 15 dB with respect to the one without classification. [ABSTRACT FROM AUTHOR]

The nuclear pore complex profoundly affects the timing of flowering; however, the underlying mechanisms are poorly understood. Here, we report that Nucleoporin96 (Nup96) acts as a negative regulator of long-day photoperiodic flowering in Arabidopsis (Arabidopsis thaliana). Through multiple approaches, we identified the E3 ubiquitin ligase HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE1 (HOS1) and demonstrated its interaction in vivo with Nup96. Nup96 and HOS1 mainly localize and interact on the nuclear membrane. Loss of function of Nup96 leads to destruction of HOS1 proteins without a change in their mRNA abundance, which results in overaccumulation of the key activator of long-day photoperiodic flowering, CONSTANS (CO) proteins, as previously reported in hos1 mutants. Unexpectedly, mutation of HOS1 strikingly diminishes Nup96 protein level, suggesting that Nup96 and HOS1 are mutually stabilized and thus form a novel repressive module that regulates CO protein turnover. Therefore, the nup96 and hos1 single and nup96 hos1 double mutants have highly similar early-flowering phenotypes and overlapping transcriptome changes. Together, this study reveals a repression mechanism in which the Nup96-HOS1 repressive module gates the level of CO proteins and thereby prevents precocious flowering in long-day conditions. [ABSTRACT FROM AUTHOR]

Key message: Two redundant nucleoporin genes Nup98a and Nup98b bypass the CO-check point in photoperiodic signaling and integrated signals from multiple pathways to directly target FT for flowering control in Arabidopsis. Flowering regulation is an important and widely studied plant development event. Even though nucleoporin Nup98 has been proven to play pivotal roles in the growth and development of mammalian cells and yeast, it is still unknown if Nup98 participates in flowering control in plants. In this study, we investigated the function of two Nup98 homologs, Nup98a and Nup98b, in flowering regulation in Arabidopsis. The results showed that Nup98a and Nup98b redundantly inhibit flowering through multiple pathways including clock, photoperiod, and age pathways. Single mutants of nup98a and nup98b do not show any obvious abnormal phenotypes compared to wild-type plants; however, the nup98a1 nup98b1 double mutant displays early flowering. Significantly, Nup98a/Nup98b gate flowering in a CONSTANS (CO)-independent mode. Therefore, Nup98a/Nup98b bypasses the CO checkpoint in photoperiodic signaling and integrated signals from multiple pathways to directly target FLOWERING LOCUS T (FT) for flowering control. In addition, our results provide a line of genetic evidence for uncoupling the mechanism of flowering and senescence at Nup98a/Nup98b genes in Arabidopsis, which are classically recognized as two coupled developmental events. [ABSTRACT FROM AUTHOR]

• The feasibility of weight and center-of-gravity estimation based on the aircraft trim data is qualitatively analyzed, and the trim data calculation method for the aircraft with variable center of mass is introduced. • On the basis of the aircraft trim data, a novel estimation method for aircraft weight and the longitudinal center-of-gravity position via inverse interpolation is presented. • An improved moving average filter is introduced to eliminate the adverse effect on estimation results caused by the high-frequency noise of airborne sensors. • Some simulations are operated, and the impact of the weight estimation error and the elevator deflection measurement error on the estimation result of center-of-gravity is discussed. Aircraft weight and center-of-gravity are significant parameters that affect flight stability and controllability, and unreasonable CG position may cause serious flight accidents. However, there is no airborne sensor can directly measure aircraft weight and center-of-gravity. In view of this, a novel estimation method for weight and center-of-gravity via the aircraft trim data is introduced. Specifically, the trim data calculation process for the aircraft with variable center of mass is given. Then, an inverse interpolation approach based on the binary search algorithm is presented to estimate the aircraft weight and center-of-gravity, and an improved moving average filter is introduced to eliminate the adverse effect on estimation results caused by the high-frequency noise of airborne sensors. Some simulations are given to demonstrate the validity of the proposed estimation method, and it can be drawn from the result that the aircraft longitudinal CG position estimation error is within 0.05 %MAC. [ABSTRACT FROM AUTHOR]

The authors signal an error in Fig. 1b which does not show the correct set of plants and should be replaced with the included new figure. [ABSTRACT FROM AUTHOR]

Porous magnetite nanoparticles were successfully synthesized by reduction of titanium residue with pyrite under nitrogen protection, and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, vibrating sample magnetometer, X-ray photoelectron spectroscope, zeta potential and Brunauer–Emmett–Teller method. The XRD analysis confirmed the formation of porous magnetite nanoparticles with single spinel structure. The SEM image demonstrated that porous magnetite nanoparticles displayed spherical shape with the average diameter of ~ 51 nm. The surface area of porous magnetite nanoparticles with high magnetic moment (78 emu·g − 1 ) was 11.1 m 2 g − 1 . The experimental results revealed that equilibrium adsorption behavior of Cr(VI) was well described by Langmuir isotherm model with the maximum adsorption capacity of 14.49 mg g − 1 at 298.15 K, and kinetic data was found to fit well with pseudo-second-order model. The adsorption rate for Cr(VI) was controlled by both boundary layer diffusion and intraparticle diffusion. Thermodynamics analysis showed that the adsorption processes of Cr(VI) were endothermic and spontaneous. In addition, the adsorption of Cr(VI) on porous magnetite nanoparticles was classified as chemisorption adsorption, which depended on electrostatic attraction accompanied with reduction of Cr(VI) to Cr(III). Porous magnetite nanoparticles were readily regenerated and used repeatedly for Cr(VI) adsorption at least five cycles. Furthermore, the experimental results indicate that porous magnetite nanoparticles have a promising application for Cr(VI) adsorption from wastewater. [ABSTRACT FROM AUTHOR]

To satisfy the increasing requirements for high-quality cavity mirrors for semiconductor lasers, the influence of the anisotropic stress field generated by scratching GaAs on the quality of cleavage planes was investigated. First, a novel method for calculating the interplanar spacing was proposed to estimate the favourable direction for the scratching operation. Some mechanical properties in the scratching direction were calculated. Consequently, an anisotropic calculation model of the stress field generated by scratching was established. The calculation model was used to analyse the y-component stress field distribution along different directions beneath the indenter. The results show that the maximum stress occurs at the contact area between the material and indenter tip, and the stress along the <100> orientation is lower than that along the <110> orientation. According to our experiments, a significant decrease in the average radial crack length and a slight decrease in the average kerf width were observed along the [011] direction compared to the corresponding results for the [001] direction. In addition, the (011) plane had a surface roughness of 0.43 nm and could become a preferential cleavage plane under a low scratching load. The results of this study contribute to advance our understanding of the mechanisms of mechanical cleavage processes. [ABSTRACT FROM AUTHOR]

Synthetic aperture radar (SAR) image-change detection is widely used in various fields, such as environmental monitoring and ecological monitoring. There is too much noise and insufficient information utilization, which make the results of change detection inaccurate. Thus, we propose an SAR image-change-detection method based on multiplicative fusion difference image (DI), saliency detection (SD), multi-scale morphological reconstruction (MSMR), and fuzzy c-means (FCM) clustering. Firstly, a new fusion DI method is proposed by multiplying the ratio (R) method based on the ratio of the image before and after the change and the mean ratio (MR) method based on the ratio of the image neighborhood mean value. The new DI operator ratio–mean ratio (RMR) enlarges the characteristics of unchanged areas and changed areas. Secondly, saliency detection is used in DI, which is conducive to the subsequent sub-area processing. Thirdly, we propose an improved FCM clustering-change-detection method based on MSMR. The proposed method has high computational efficiency, and the neighborhood information obtained by morphological reconstruction is fully used. Six real SAR data sets are used in different experiments to demonstrate the effectiveness of the proposed saliency ratio–mean ratio with multi-scale morphological reconstruction fuzzy c-means (SRMR-MSMRFCM). Finally, four classical noise-sensitive methods are used to detect our DI method and demonstrate the strong denoising and detail-preserving ability. [ABSTRACT FROM AUTHOR]

To investigate the predictive efficacy of the preoperative neutrophil–lymphocyte ratio (NLR) for natural pregnancy outcome after laparoscopic cystectomy in infertile patients with ovarian endometrioma (OMA). Current evidence suggests that endometriosis likely induces local and systemic inflammatory processes. The NLR has been demonstrated to be of great utility in the diagnosis of endometriosis. However, the association between NLR and natural pregnancy outcome after laparoscopic surgery for endometriosis remains unknown. Data on infertile OMA patients undergoing laparoscopic surgery from January 2014 to October 2019 were retrospectively analyzed. Cox regression analysis was used to identify predictors of natural pregnancy outcome. A predictive model was then established using the nomogram. Among 217 patients, 115 patients (53.0%) experienced natural pregnancy after surgery. Compared with patients with pregnancy failure, those with pregnancy success had a significantly higher NLR (P < 0.05). Multivariate analysis revealed that age, least function (LF) score, and NLR were independent predictors of postoperative pregnancy (all P < 0.05). The NLA (NLR, LF score and age) scoring was then established and had a high predictive ability (AUC = 0.725). Patients were divided into three groups (low-, intermediate- and high-risk) based on the scoring, and the 1-year pregnancy rates were 43.5%, 34.4%, and 21.0%, respectively (P < 0.05). The preoperative NLR level was significantly associated with natural pregnancy outcome in infertile OMA patients after surgery. A predictive model combining NLR, LF score, and age could assist in the clinical decision-making process. [ABSTRACT FROM AUTHOR]

In order to promote the cleavage technology of GaAs, this paper explored the influence of the crystallographic orientation of mechanical properties on the quality of cleavage plane. Systematic theoretical models of certain key mechanical properties were proposed, and the mechanism of crack formation along two different directions during the cleavage process was discussed. The indentation tests were used to evaluate the crack formation and indentation morphology. A series of cleavage experiments were carried out to investigate the influence of mechanical properties and crack formation on the cleavage process. The results show that the Young's modulus, Poisson's ratio and Vickers hardness in the (100) plane along the <110> directions are 121.26 GPa, 0.02 and 5.757 GPa, respectively, and the values along the <100> directions are 85.26 GPa, 0.31 and 6.091 GPa, respectively. Combining theoretical calculations and indentation test results, the average fracture toughness in the <100> directions is approximately 10.94% higher than that in the <110> directions. Meanwhile, scratching along the <110> directions helps reduce the damage width. The {110} plane is a favorable cleavage plane in GaAs. These findings indicate that cleaving along the directions with a low fracture toughness is much easier to obtain a smooth cleavage plane. In addition, this paper proposed a useable theoretical and experimental approach to calculate mechanical properties for obtaining high-quality cleavage planes that can be widely used in other semiconductor materials. [ABSTRACT FROM AUTHOR]

Synthetic aperture radar (SAR) operating in an along-track interferometric (ATI) mode has the advantage of minimum detectable velocity (MDV) in active marine target detection. However, most of the conventional ATI detectors fail to identify the marine targets cruising with blind speeds, in which case the interferometric phases of these targets are closely distributed around those of the sea background due to phase wrapping and aliasing through ATI processing. To address this issue, we propose a method to detect the active marine targets based on complex interferometric dissimilarity for dual-channel ATI-SAR systems. First, an interferometric bilateral filter is designed to smooth the random noises and locally adapt to the spatial structure of the interferogram for measuring the interferometric magnitude and phase. Then, the target detection metric is constructed based on the complex interferometric dissimilarity between the marine targets and the sea background. By adaptively regressing into a magnitude-based test toward the blind-speed targets, the target detection metric can mitigate the blind-speed detection problem and thus yield a satisfactory detection result. Furthermore, this metric is of a constant false-alarm rate (CFAR), and its probability density function (pdf) is derived to facilitate the detection threshold computation. Finally, both the simulated and real-data processing results are given to validate the superiorities of the proposed method. [ABSTRACT FROM AUTHOR]

The West Junggar of the western Central Asian Orogenic Belt is one of the typical regions in the term of ocean subduction, contraction and continental growth in the Late Paleozoic. However, it is still controversial on the exact time of ocean‐continent transition so far. This study investigates rhyolites with columnar joint in the West Junggar for the first time. Based on zircon U‐Pb dating, we determined that the ages of the newly‐discovered rhyolites are between 303.6 and 294.5 Ma, belonging to Late Carboniferous–Early Permian, which is the oldest rhyolite with columnar joint preserved in the world at present. Geochemical results show that the characteristics of the major element compositions include a high content of SiO2 (75.78–79.20 wt%) and a moderate content of Al2O3 (12.21–13.19 wt%). The total alkali content (K2O + Na2O) is 6.14–8.05 wt%, among which K2O is 2.09–4.72 wt% and the rate of K2O/Na2O is 0.38–3.05. Over‐based minerals such as Ne, Lc, and Ac do not appear. The contents of TiO2 (0.09–0.24 wt%), CaO (0.15–0.99 wt%) and MgO (0.06–0.18 wt%) are low. A/CNK=0.91–1.68, A/NK=1.06–1.76, and as such, these are associated with the quasi‐aluminum‐weak peraluminous high potassium calc‐alkaline and some calc‐alkaline magma series. These rhyolites show a significant negative Eu anomaly with relative enrichment of LREE and LILE (Rb, Ba, Th, U, K) and depletion of Sr, HREE and HFSE (Nb, Ta, Ti, P). These rhyolites also have the characteristics of an A2‐type granite, similar to the Miaoergou batholith, which indicates they both were affected by post‐orogenic extension. Combining petrological, zircon U‐Pb dating and geochemical characteristics of the rhyolites, we conclude that the specific time of ocean‐continent transition of the West Junggar is the Late Carboniferous–Early Permian. [ABSTRACT FROM AUTHOR]

Abstract The growth of the Tibetan Plateau resulted primarily from India-Asia convergence since initial collision at 65–55 Ma. The Cenozoic Qilian Shan thrust belt and the left-slip strike Haiyuan fault system together define the northeastern margin of the plateau. Although these thrust and strike-slip fault systems play an important role in accommodating continental convergence, our knowledge of the temporal and spatial distribution of upward and outward growth of the northeastern Tibetan Plateau is still lacking. In this study, we integrate new geologic mapping and low-temperature themochronometry (apatite- and zircon-fission-track ages) to provide constraints on the uplift and cooling history of the North Qilian Shan and the initiation of the Haiyuan fault. Cooling ages and thermal history modeling from a traverse across a prominent restraining bend on the Haiyuan fault suggest the North Qilian Shan experienced a three-phase cooling history, including: (1) broad cooling during the Late Triassic to early Cenozoic, (2) long-term tectonic quiescence from late Cretaceous to middle Miocene, and (3) rapid cooling and exhumation from ~15–10 Ma to present. We relate this most recent local cooling (~15–10 Ma) to the initiation of strike-slip faulting along the central Haiyuan fault, which corroborates other recent studies, suggesting a middle Miocene activation of strike-slip deformation along the Haiyuan fault in northern Tibet. Highlights • Thermochronology was conducted across a restraining bend of the Haiyuan fault. • The North Qilian Shan records three-stage cooling starting in the Late Triassic. • Strike-slip faulting along the central Haiyuan fault initiated at ~15–10 Ma [ABSTRACT FROM AUTHOR]

The West Junggar Metallogenic Belt (WJMB) is located between the Tianshan fault system and the Ertix fault system in the western part of the Central Asian Metallogenic Domain (CAMD). The belt features widespread late Palaeozoic granitic plutons, strike-slip faults, and porphyry copper and orogenic gold deposits. We collected nine molybdenite samples from the Baogutu III–IV Cu–Mo deposit and the Suyunhe Mo–W deposit, and 12 granitoid samples from the Jiaman, Kangde, Kulumusu, Bieluagaxi, Hatu, Akbastau, Miaoergou, Baogutu, Karamay, and Hongshan plutons in the WJMB. Molybdenite Re–Os dating gives metallogenesis ages of 312.7 and 299.7 Ma for the Baogutu III–IV and Suyunhe deposits, respectively.40Ar/39Ar thermochronology yields biotite ages ranging from 326 to 302 Ma and K-feldspar ages from 297 to 264 Ma, indicating a regional medium-temperature cooling history in the WJMB during the late Carboniferous to middle Permian. By integrating these data with previous zircon U–Pb, amphibole40Ar/39Ar, and zircon and apatite fission-track ages, we reconstruct the whole thermal history of the WJMB, which includes late Palaeozoic intrusive magmatism, porphyry Cu and W–Mo mineralization, and late Mesozoic tectonic uplift and exhumation of the WJMB. The regional40Ar/39Ar cooling ages are consistent with the timing of regional sinistral strike-slip faulting, thereby indicating the tectonic significance of the cooling ages. We suggest that the biotite40Ar/39Ar ages represent the static cooling of the granitic plutons after emplacement, since the ages are consistent with the U–Pb ages of the plutons. Thereafter, the oldest K-feldspar40Ar/39Ar age may record the initiation of sinistral strike-slip movement on the Darabut, Mayile, and Baerluke faults. The regional faulting resulted in significant uplift of the WJMB during the early and middle Permian. [ABSTRACT FROM PUBLISHER]

Eastern Qaidam Basin of the northern Qinghai-Tibetan plateau is located in a transitional zone between the Permo–Triassic Paleo-Tethyan orogenic belt in the south and the early Paleozoic Qilian orogenic belt in the north. Here we present geochemical and Sr–Nd–Pb–O isotopic data for the Permo–Triassic plutons in eastern Qaidam Basin. Bulk-rock geochemical data and regional geological studies indicate that these plutons consist mainly of subduction-related high-K calc-alkaline metaluminous, I-type granitoids, which occurred during the northward subduction of the Paleo-Tethyan oceanic lithosphere below the southern continental margin of the Kunlun–Qaidam terrane. The ε Nd( t ) values of these Permo–Triassic granitoids are between −9.4 and −3.0, and ε Sr( t ) values are from −20.33 to +168.20. Nd isotopic compositions indicate that the granitoids can come from a pre-existed materials formerly originated from an enriched mantle (EM II) source. The T DM2 model ages of 1.28–1.78 Ga implies that the arc-induced Triassic granitoids were derived melts of Meso-Proterozoic basement rocks of the Kunlun–Qaidam terrane that is bounded by the early Paleozoic Qilian suture zone to the north and the Triassic Kunlun suture zone in the south. The Permo–Triassic granitoids yield initial ratios of 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, and 208 Pb/ 204 Pb values from 18.295 to 19.096, 15.617 to 15.692, and 37.960 to 38.531, respectively. The Pb isotope composition of the granitoids is very similar to that of the Mesozoic granitoids from the western segment of the east of the study area. Geochemical analyses of the plutons, integrated with previous LA ICP-MS U–Pb zircon dating, reveal two series of Permo–Triassic arc magmatisms in eastern Qaidam Basin. Both the series of magmatism display reversed trends with the classic Bowen’s reaction series. The new geochemical evidence suggest that the arc magmatism in eastern Qaidam Basin was induced by fluid-fluxing melting of an enriched lithospheric mantle and rock composition is best explained by mixing of mantle-derived mafic magma mixed with felsic rocks of the Qaidam basement. [ABSTRACT FROM AUTHOR]

With the increase in satellite communication interference, the tri-satellite time difference of arrival (TDOA) localization technique, which is an effective method to determine the location of the interference using sensors or antennas, has been developed rapidly. The location of the interference source is determined through the intersection of the TDOA lines of position (LOP). However, when the two TDOA LOP have two mirrored intersection points, it is theoretically difficult to determine the real location. Aiming at this problem, a method for eliminating mirrored location based on multiple moment TDOA is proposed in this paper. First, the TDOA results are measured at multiple moments using the cross-ambiguity function (CAF), and the localization equation set is established based on the World Geodetic System (WGS)-84 earth ellipsoid model. Then, the initial location result can be obtained by solving the equation set through the Newton iteration method. Finally, the high-precision location result after eliminating the mirrored location is obtained after the single moment localization based on the initial location. Simulation experiments and real measured data processing results verify the effectiveness of the proposed method. It still has good robustness under the condition of large measurement errors and deviations from the prior initial values. [ABSTRACT FROM AUTHOR]