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As a general behavior in civil social life, how can personal health information disclosure be affected by social structural factors when using the health application? This study used the Social Capital Theory to examine the personal health information behavior. Nationally representative cross-sectional survey data generated by the China Family Panel Studies(CFPS) in 2020 was utilized(N = 8628). Logistic regression analysis was employed to analyze the data. After controlling for age, gender, and education covariates, social interaction had no significant impact on health APP information disclosure behavior (OR=0.988),there is a significant positive relationship between trust(OR=1.282)/ reciprocity perception(OR=1.134) and health APP information disclosure behavior. More relational social capitals can enhance individual social trust, maintain reciprocity perception, maintain the balance and stability of social exchange relations.This study extends the application of social capital theory in the study of personal health information disclosure, providing theoretical support for the democratization process of social health governance.

In this article, the bond performance between recycled concrete and corroded steel bars is analyzed by the nonlinear numerical simulation. The result shows that the maximum bond strength between recycled concrete and steel bar decreases with the increase in steel bar corrosion rate; when the recycled concrete strength is large, the simulated maximum bond strength is in good agreement with the experimental maximum bond strength; when the recycled concrete strength is small, the simulated maximum bond strength is in relatively poor agreement with the experimental maximum bond strength, but there is still an error within the allowable range; the slip between recycled concrete and steel bar increases with the increase in steel bar corrosion rate; when the steel bar corrosion rate exceeded 5%, the bond strength decreases more rapidly; the maximum bond strength increases with the increase in specimen sizes under the same steel bar corrosion rate; the maximum bond strength decreases with the increase in steel bar diameter under the same steel bar corrosion rate.

This paper studied the mechanical performance of aerated concrete and its bonding performance with glass fiber grille, and explores the influence of aluminum powder and aluminum powder on mechanical performance and bonding performance. The results showed that the compressive strength of aerated concrete decreased with the increase of aluminum powder content, while it first increased and then decreased with the increase of ferrosilicon alloy powder content. The failure modes of specimens were fiber fracture failure, and the fibers were not pulled out from the aerated concrete. It can provide a theoretical basis for the application of aerated concrete and glass fiber in engineering.

In most sexually reproducing plants, a single somatic, sub-epidermal cell in an ovule is selected to differentiate into a megaspore mother cell, which is committed to giving rise to the female germline. However, it remains unclear how intercellular signaling among somatic cells results in only one cell in the sub-epidermal layer differentiating into the megaspore mother cell. Here we uncovered a role of the THO complex in restricting the megaspore mother cell fate to a single cell. Mutations in TEX1, HPR1, and THO6, components of the THO/TREX complex, led to the formation of multiple megaspore mother cells, which were able to initiate gametogenesis. We demonstrated that TEX1 repressed the megaspore mother cell fate by promoting the biogenesis of TAS3-derived trans-acting small interfering RNA (ta-siRNA), which represses ARF3 expression. The TEX1 protein was present in epidermal cells, but not in the germline, and, through TAS3-derived ta-siRNA, restricted ARF3 expression to the medio domain of ovule primordia. Expansion of ARF3 expression into lateral epidermal cells in a TAS3 ta-siRNA-insensitive mutant led to the formation of supernumerary megaspore mother cells, suggesting that TEX1- and TAS3-mediated restriction of ARF3 expression limits excessive megaspore mother cell formation non-cell-autonomously. Our findings reveal the role of a small-RNA pathway in the regulation of female germline specification in Arabidopsis.

Scutellaria baicalensis Georgi (SB), a plant of the Lamiaceae family, contains flavonoids with potent human health benefits. The full mechanistic details and regulatory networks related to the biosynthesis of these compounds in SB have been the focus of recent research but are still fragmented. Similarly, a complete account of the metabolites produced, specifically flavonoids, and their distribution in different parts of the plant is incomplete. To provide a more complete picture, herein we have explored the SB metabolites and differentially expressed genes in underground and aerial tissues. Of the 947 metabolites identified, 373 were differentially accumulated flavonoids (DAFs), and 147 of these were differentially accumulated in roots relative to other tissues. Interestingly, roots accumulated more baicalin and baicalein than aboveground tissues, but they were low in scutellarein and wogonoside, in contrast to previous reports. These differences may be attributed to either plant variety, age of the plants, or the extraction protocol. Transcriptomics analysis identified 56 key genes from the flavonoid synthesis pathway in all six SB plant tissues. A weighted gene correlation network analysis conducted using four DAFs (baicalin, baicalein, scutellarein and wogonoside) produced 13 modules. Baicalin and baicalein were positively correlated with one of these modules, whereas wogonoside and scutellarein were correlated with three other modules. Gene expression in these modules was consistent with the observed accumulation of these compounds in plant tissues. Fourteen structural genes were highly correlated with baicalin, baicalein and scutellarein, and 241 transcription factors (TFs) associated to these four compounds. The 13 highly correlated structural genes and 21 highly correlated TFs were used to construct correlation networks, where genes were identified to be highly correlated with flavonoid biosynthesis genes. Overexpression of some of these genes, namely, SbMYB8 (Sb02g25620), SbMYB14 (Sb09g00160) and SbbHLH94 (Sb07g11990), in SB callus increased flavonoid content and regulated the expression of genes involved in the flavonoid biosynthesis pathway, confirming their association to flavonoid production. Overall, the present work contributes to delineating the differences in flavonoid biosynthesis among different SB tissues. [ABSTRACT FROM AUTHOR]

An indispensable step in the imaging of Tomographic Synthetic Aperture Radar (TomoSAR) in spectral analysis or Compressive Sensing (CS) technology is estimating the perpendicular baselines in the Perpendicular Line Of Sight (PLOS) in deramping operations. To avoid this procedure, we introduce a Beam Forming (BF) method in the spatial domain that scans for TomoSAR focusing in the PLOS direction. Because of the sophisticated structure of buildings in urban areas, multipass high-resolution SAR images suffer from discrepancies in the look and incidence angles as well as speckle noise. As a result, it is challenging to precisely coregister all the homologous points in the identical pixels of multipass SAR images. To identify the most relevant pixels with respect to both amplitude and phase when BF imaging is implemented, we propose an inconsistency criterion for specific pixels using the joint phase and amplitude of pixels in a window. By minimizing the inconsistency criterion, homologous points with high accuracy can be identified by focusing on TomoSAR imaging. We used simulation and real data from a multipass X-band airborne TomoSAR system in China to test the effectiveness of the proposed method. Experimental results show that the peak of the reflectivity profile via conventional tomographic imaging is about 15.63 m, whereas that by the proposed method is 16.88 m, which is very close to the actual height of the 18 m building. The results demonstrate the feasibility of improving the focusing power of scatterers in the PLOS direction and extracting the threedimensional outliers of buildings.

Using azimuth beam steering, space-borne Synthetic Aperture Radar (SAR) can observe from multiple azimuth angle in single pass. During multiple azimuth angle observation, the satellite orbit is equivalent to long three-dimensional (3-D) curvilinear array, which has the potential for 3-D imaging. Sampling by space-borne multiple azimuth angle SAR is sparse in height dimension, which makes unambiguous 3-D imaging by 3-D fast Fourier transform infeasible. Besides, the complex relationship between the targets’projection in multi-angle SAR images and the height error is difficult to determine. To overcome this limitation, in this paper, we present a 3-D imaging method based on joint multiple azimuth angle Doppler frequency rate estimation. First, a relationship is proposed between the height error and Doppler frequency rate at different azimuth angle. Then, the Doppler frequency modulation rate error is estimated by Map Drift (MD) technique. Next, the height estimation results of different azimuth angle are combined to improve the estimation accuracy. From the estimated height and the target location in the SAR images, 3-D geometric information is retrieved and 3-D imaging is achieved. Our simulation experiments validate that the height estimation can achieve an accuracy of few meters with the proposed method.

Polarimetric Synthetic Aperture Radar (PolSAR) data is inherently characterized by speckle noise, which significantly deteriorates certain aspects of the quality of the PolSAR data processing, including the polarimetric decomposition and target interpretation. With the rapid increase in PolSAR resolution, SAR images in complex natural and artificial scenes exhibit non-homogeneous characteristics, which creates an urgent demand for high-resolution PolSAR filters. To address these issues, a new adaptive PolSAR filter based on joint similarity measure criterion (JSMC) is proposed in this paper. Firstly, a scale-adaptive filtering window is established in order to preserve the texture structure based on a multi-directional ratio edge detector. Secondly, the JSMC is proposed in order to accurately select homogeneous pixels; it describes pixel similarity based on both space distance and polarimetric distance. Thirdly, the homogeneous pixels are filtered based on statistical averaging. Finally, the airborne and spaceborne real data experiment results validate the effectiveness of our proposed method. Compared with other filters, the filter proposed in this paper provides a better outcome for PolSAR data in speckle suppression, edge texture, and the preservation of polarimetric properties. [ABSTRACT FROM AUTHOR]

To address the issues of the brittleness, low tensile strength, insufficient bond strength, and reduced service life associated with ordinary cement concrete being used as a repair material, a water-based epoxy (WBE) and carbon-nanofiber-reinforced concrete composite repair material was designed, and the mechanical properties, bonding performance, and durability of the concrete modified using WBE and carbon fiber under various WBE contents were investigated and evaluated. In this paper, a self-emulsifying water-based epoxy curing agent with reactive, rigid, flexible, and water-soluble chains was obtained via chemical grafting, involving the incorporation of polyethylene glycol chain segments into epoxy resin molecules. The results demonstrated that a WBE has a contributing effect on improving the weak interfacial bond between the carbon fiber and concrete; moreover, the composite admixture of carbon fiber and WBE improves the mechanical properties and durability of concrete, in which the composite admixture of 1% carbon fiber and 10% WBE has the best performance. The flexural strength and chlorine ion permeability resistance of concrete were slightly reduced after more than 10% admixture, but bond strength, tensile strength, compressive strength, dry shrinkage resistance, and frost resistance were promoted. The addition of WBE significantly retards the cement hydration process while greatly improving the compactness and impermeability of the concrete. Furthermore, the combined effects of WBE and carbon fiber effectively prevented the generation and expansion of cracks. The interaction mechanism and microstructure evolution between the WBE, carbon fiber, and cement hydration were described by clarifying the mineral composition, organic–inorganic interactions, the evolution of the hydration products, and composite morphology at different scales. Carbon fiber and WBE exhibited synergistic effects on the tensile strength, ductility, and crack resistance of concrete. In the formed three-dimensional network structural system of concrete, the WBE formed an organic coating layer on the fiber surface and provided fiber protection as well as interfacial bonding reinforcement for the embedded cement particles. [ABSTRACT FROM AUTHOR]

The transporter associated with antigen processing (TAP) translocates antigenic peptides from the cytosol into the lumen of the endoplasmic reticular and plays a critical role in the major histocompatibility complex (MHC) class I molecule-mediated antigenic presentation pathway. In this study, the porcine TAP1 gene was mapped to the pig chromosome 7 (SSC7) and was closely linked to the marker SSC2B02 (retention fraction=43%, LOD=15.18). Subcellular localization of TAP1 by transient transfection of PK15 cells indicated that the TAP1 protein might be located in the endoplasmic reticulum (ER) in pig kidney epithelial cells (PK-15). Gene expression analysis by semi-quantitative RT-PCR revealed that TAP1 was selectively expressed in some immune and immune-related tissues. Quantitative real-time PCR (qRT-PCR) analysis revealed that this gene was up-regulated after treatments that mimic viral and bacterial infection (polyriboinosinic-polyribocytidylic acid (poly(I:C)) and lipopolysaccharide (LPS), respectively). In addition, elevated TAP1 expression was detected after porcine reproductive and respiratory syndrome virus (PRRSV) infection in porcine white blood cells (WBCs). One single nucleotide polymorphism (SNP) in exon 3 of TAP1 was detected in a Landrace pig population by Bsp143I restriction enzyme digestion. Different genotypes of this SNP had significant associations (PP=0.0168), the PRRSV antibody level (PRRSV Ab) (P=0.0445) and the absolute lymphocyte count (LYM#) (P=0.024) of 17 d pigs. Our results showed that the TAP1 gene might have important roles in swine immune responses, and these results provide useful information for further functional studies.

As is well known, image coregistration, interferometric phase noise suppression, and phase unwrapping are three key processing procedures of synthetic aperture radar interferometry (InSAR). The three procedures are cascaded in the conventional processing flow of InSAR. Unlike the conventional processing flow, in this paper we propose a joint processing idea to carry out image coregistration, interferometric phase noise filtering, and phase unwrapping simultaneously based on subspace projection for muitibaseline InSAR systems. The joint processing method can perform the fine coregistration of all SAR images implicitly by extracting the correlation information in the neighboring pixel sets, suppress the phase noise by utilizing the orthogonality of the signal subspace and the corresponding noise subspace, and optimally estimate the unwrapped interferometric phases (or the terrain heights) by combining the pixel coherence and the baseline diversity of a multibaseline InSAR system. Simulated results are presented to verify the effectiveness of the joint processing method. Index Terms--Digital elevation model (DEM), image coregistration, interferogram, multibaseline, phase unwrapping, subspace projection, synthetic aperture radar interferometry (InSAR).

A new concept of spaceborne synthetic aperture radar (SAR) implementation has recently been proposed--the constellation of small spaceborne SAR systems. In this implementation, several formation-flying small satellites cooperate to perform multiple space missions. We investigate the possibility to produce high-resolution wide-area SAR images and fine ground moving-target indicator (GMTI) performance with constellation of small spaceborne SAR systems. In particular, we focus on the problems introduced by this particular SAR system, such as Doppler ambiguities, high sparseness of the satellite array, and array element errors. A space-time adaptive processing (STAP) approach combined with conventional SAR imaging algorithms is proposed which can solve these problems to some extent. The main idea of the approach is to use a STAP-based method to properly overcome the aliasing effect caused by the lower pulse-repetition frequency (PRF) and thereby retrieve the unambiguous azimuth wide (full) spectrum signals from the received echoes. Following this operation, conventional SAR data processing tools can be applied to focus the SAR images fully. The proposed approach can simultaneously achieve both high-resolution SAR mapping of wide ground scenes and GMTI with high efficiency. To obtain array element errors, an array auto-calibration technique is proposed to estimate them based on the angular and Doppler ambiguity analysis of the clutter echo. The optimizing of satellite formations is also analyzed, and a platform velocity/PRF criterion for array configurations is presented. An approach is given to make it possible that almost any given sparse array configuration can satisfy the criterion by slightly adjusting the PRF. Simulated results are presented to verify the effectiveness of the proposed approaches.

In this paper, we propose a new method to estimate synthetic aperture radar interferometry (InSAR) interferometric phase in the presence of large coregistration errors. The method takes advantage of the coherence information of neighboring pixel pairs to automatically coregister the SAR images and employs the projection of the joint signal subspace onto the corresponding joint noise subspace to estimate the terrain interferometric phase. The method can automatically coregister the SAR images and reduce the interferometric phase noise simultaneously. Theoretical analysis and computer simulation results show that the method can provide accurate estimate of the terrain interferometric phase (interferogram) as the coregistration error reaches one pixel. The effectiveness of the method is also verified with the real data from the Spaceborne Imaging Rada-C/X Band SAR and the European Remote Sensing 1 and 2 satellites. Index Terms--Image coregistration, interferograms, interferometric phase estimation, phase unwrapping, subspace projection, synthetic aperture radar interferometry (InSAR).