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In this paper, an effective method for substrate integrated waveguide (SIW) filter with improved stop band performance is proposed. By configuring the position and the direction of the coupling window, the transmission of the parasitic mode such as TE 102 and TE 201 can be effectively suppressed without adding any extra structure and element. Under the above theory, a Ka-band SIW filter centered at 35.71 GHz based on quartz glass substrate with compact size and simple structure is designed and tested. The stop rejection of the design is increased from 1.03 times to 1.95 times the center frequency within −35 dB of the filter with the insertion loss of −2.5 dB and the return loss of −20 dB. Finally, the measurement results validated the proposed design. [ABSTRACT FROM AUTHOR]

Keep-out-zone (KOZ) is a conservative way to prevent any devices/cells from being impacted by the through-silicon-via (TSV)-induced stress. In this paper, an effective approach was proposed of reducing the KOZ induced by coaxial TSV, by using the structure of coaxial-annular TSV, without decreasing the electrical performance of coaxial TSV. The analytical model was developed appropriate for the thermal stress induced by both coaxial and coaxial-annular TSVs, and was verified by the finite element method. The KOZs induced by coaxial and coaxial-annular TSVs were compared in detail, and the effects of Cu plasticity, TSV material, TSV size, and inner metal plating ratio of coaxial-annular TSV were also studied. The electrical characteristics of different TSVs were compared by employing ANSYS’ HFSS, and a feasible fabrication process for coaxial-annular TSV was suggested. It could be concluded that: 1) a 1.6- \(\mu \) m (22.2%) drop of KOZ for coaxial-annular TSV could be reached as compared with that of coaxial TSV; 2) coaxial-annular TSV was proved to offer the same superior signal integrity with coaxial TSV, improving S21 by about 93% at 5 GHz and 60% at 20 GHz compared with ordinary cylindrical and annular TSVs; and 3) the coaxial-annular TSV is realizable. [ABSTRACT FROM AUTHOR]

The vast volume expansion of Si anode during lithiation process leads to poor cyclability and low initial coulombic efficiency (ICE), and thus seriously hampers its applications in lithium-ion batteries (LIBs). To overcome these obstacles, in this study, a double core-shell structure stabilized hierarchical porous Si (p-Si) microsphere was synthesized through a graphene-involved electrostatic self-assembly process coupled with a solvent-confined TiO 2 (sc-TiO 2) monomicelle assembly strategy. The advanced solvent-confined monomicelle assembly process enables the uniform deposition of ultra-thin TiO 2 layer on p-Si@graphene (p-Si@G) microsphere. The G/sc-TiO 2 hybrid double shell layer can significantly consolidate porous structure of p-Si microsphere and simultaneously improve the ICE value of p-Si@G@sc-TiO 2 microsphere. The resulting p-Si@G@sc-TiO 2 composite shows a high capacity value of 2597.9 mAh g−1 at 0.2 A g−1 with a high ICE value of 80.59%. The p-Si@G@sc-TiO 2 composite also demonstrates excellent rate capability with capacity of 802.53 mAh g−1 at 8 A g−1 and outstanding cyclability with capacity retention of 68% (1005.1 mAh g−1) after 300 cycles at 2 A g−1, superior to that of p-Si, p-Si@G as well as p-Si@G@TiO 2 microsphere preparing by traditional sol-gel TiO 2 coating method, suggesting its promising applications in LIBs. [ABSTRACT FROM AUTHOR]

Exploring the response of spatial and temporal characteristics of ecological quality change to aridity on the Qinghai–Tibet Plateau (QTP) can provide valuable information for regional ecological protection, water resource management, and climate change adaptation. In this study, we constructed the Remote Sensing Ecological Index (RSEI) and Standardized Precipitation Evapotranspiration Index (SPEI) based on the Google Earth Engine (GEE) platform with regional characteristics and completely analyzed the spatial and temporal variations of aridity and ecological quality on the QTP in the years 2000, 2005, 2010, 2015, and 2020. Additionally, we explored the responses of ecological quality to aridity indices at six different time scales. The Mann–Kendall test, correlation analysis, and significance test were used to study the spatial and temporal distribution characteristics of meteorological aridity at different time scales on the QTP and their impacts on the quality of the ecological environment. The results show that the ecological environmental quality of the QTP has a clear spatial distribution pattern. The ecological environment quality is significantly better in the south-east, while the Qaidam Basin and the west have lower ecological environment quality indices, but the overall trend of environmental quality is getting better. The Aridity Index of the QTP shows a differentiated spatial and temporal distribution pattern, with higher Aridity Indexes in the north-eastern and south-western parts of the plateau and lower Aridity Indexes in the central part of the plateau at shorter time scales. Monthly, seasonal, and annual-scale SPEI values showed an increasing trend. There is a correlation between aridity conditions and ecological quality on the QTP. The areas with significant positive correlation between the RSEI and SPEI in the study area were mainly concentrated in the south-eastern, south-western, and northern parts of the QTP, where the ecological quality of the environment is more seriously affected by meteorological aridity. [ABSTRACT FROM AUTHOR]

• A magnetic SERS tags-based lateral flow assay for inflammation biomarkers detection was reported for the first time. • High-performance Fe 3 O 4 @Au nanotags served both as the SERS and concentration tools of LFA strips. • The Fe 3 O 4 @Au based SERS-strip enables quantitative analysis of SAA and CRP in whole blood samples. • The LODs for SAA and CRP were as low as 0.1 and 0.01 ng/mL, respectively. Accurate detection of mutiple biomarkers in unprocessed blood via lateral flow immunoassay (LFA) strips remains challenging. Herein, we reported a novel surface-enhanced Raman scattering (SERS)-based LFA strip for ultrasensitive and simultaneous analysis of dual infection biomarkers by using functionalized Fe 3 O 4 @Au magnetic nanoparticles (MNPs). Antibody-modified Fe 3 O 4 @Au MNPs were designed as SERS nanotags and efficient enrichment tool. The target infection biomarkers were quickly captured and enriched from the blood sample by Fe 3 O 4 @Au nanotags. After washing to remove impurities, Fe 3 O 4 @Au nanotags acted as high-performance SERS reporters for quantitative detection of the target in the LFA strip. Through this strategy, the proposed Fe 3 O 4 @Au based LFA allowed quantified analysis of target infection biomarkers in unprocessed blood samples with the limits of detection of 0.1 ng/mL and 0.01 ng/mL for serum amyloid A (SAA) and C-reactive protein (CRP), respectively. By comparison, the proposed assay for SAA and CRP was 100-fold and 1000-fold more sensitive than standard colloidal gold strip by using the same antibodies, respectively. This magnetic SERS strip also exhibited excellent stability, specificity, and selectivity for complex samples and could be used as an effective tool for infectious disease diagnostics. [ABSTRACT FROM AUTHOR]

• Primary students' perceived teacher support was positively associated with their creative thinking. • Creative self-efficacy mediated the relationship between perceived teacher support and divergent thinking. • Gender moderated the mediating effect of creative self-efficacy between perceived teacher support and divergent thinking. • The effect of perceived teacher support on divergent thinking was more pronounced in boys than girls. This study explored the relationship between perceived teacher support and primary students' creative thinking as well as the mechanism underlying these associations and gender differences. A sample of 362 primary students (196 boys) was surveyed using the Perceived Teacher Support Questionnaire, Creative Self-efficacy Scale, Divergent Thinking Test, and Remote Associate Test. The results indicated that perceived teacher support was positively associated with students' creative thinking, and creative self-efficacy mediated the relationship between perceived teacher support and divergent thinking. Additionally, gender moderated the first stage of the mediating model of creative self-efficacy between perceived teacher support and divergent thinking; specifically, the effect of perceived teacher support on divergent thinking was more pronounced in boys than girls. These findings suggest that teachers can be considered valid attachment figures for students and have a positive effect on improving primary students' creative thinking. [ABSTRACT FROM AUTHOR]

• UBPRC column has larger post-yield stiffness and smaller ultimate displacement. • UBPRC column shows better self-centering behavior but weaker energy dissipation. • FPC column suffers severe prestress loss. • The self-centering performance index can be adopted in designing UBPRC column. Unbonded prestressed reinforced concrete column (UBPRC column) has become an attractive approach in the field of bridge seismic design due to its superior self-centering behavior. Unbonded prestressing bar in a UBPRC column functions as a self-centering element and longitudinal mild reinforcement functions as an energy dissipator. Quasi-static cyclic test was carried out in this study to compare the seismic performance of reinforced concrete column (RC column), UBPRC column and fully prestressed concrete column (FPC column). The result shows that the UBPRC column has higher post-yield stiffness and smaller quasi-static residual displacement, but lower energy dissipation capability than the RC column. The FPC column suffers from the least quasi-static residual displacement, but has the lowest energy dissipation capability, the least ultimate displacement and the most severe prestress loss. The quasi-static residual displacement and residual crack width of the UBPRC column are around 66% and 73% of those of the RC column, respectively. The failure patterns of the RC column and the UBPRC column are similar, while the failure pattern of the FPC column is similar to that of a rocking column. The self-centering behavior of the three columns was analyzed and quantified using a self-centering index, which can be recommended for use in the seismic design of bridge columns. [ABSTRACT FROM AUTHOR]

Summary: Polyploidy is an important evolutionary force, yet epigenetic mechanisms, such as DNA methylation, that regulate genome‐wide expression of duplicated genes remain largely unknown. Here, we use Tragopogon (Asteraceae) as a model system to discover patterns and temporal dynamics of DNA methylation in recently formed polyploids.The naturally occurring allotetraploid Tragopogon miscellus formed in the last 95–100 yr from parental diploids Tragopogon dubius and T. pratensis. We profiled the DNA methylomes of these three species using whole‐genome bisulfite sequencing.Genome‐wide methylation levels in T. miscellus were intermediate between its diploid parents. However, nonadditive CG and CHG methylation occurred in transposable elements (TEs), with variation among TE types. Most differentially methylated regions (DMRs) showed parental legacy, but some novel DMRs were detected in the polyploid. Differentially methylated genes (DMGs) were also identified and characterized.This study provides the first assessment of both overall and locus‐specific patterns of DNA methylation in a recent natural allopolyploid and shows that novel methylation variants can be generated rapidly after polyploid formation. Together, these results demonstrate that mechanisms to regulate duplicate gene expression may arise soon after allopolyploid formation and that these mechanisms vary among genes. [ABSTRACT FROM AUTHOR]

Residual displacement serves as a crucial indicator in evaluating the safety and reparability of structures following seismic events. As a novel self-centering structure, the unbonded prestressed reinforced concrete (UBPRC) column has demonstrated its effectiveness in reducing residual displacement. However, there remains a lack of quantitative research concerning the influence of various structural and material parameters on residual displacement. For the quick and convenient evaluation of the seismic performance and resilience of UBPRC columns, in this paper, the influence of various parameters on the residual drift ratio of UBPRC columns was investigated by establishing a logarithmic linear relationship between the parameters and the residual drift ratio. These parameters include the longitudinal reinforcement and concrete strength (f y and f c), reinforcement ratio of longitudinal and transverse (ρ l and ρ s), prestressed strand ratio (ρ p), aspect ratio (A r), axial load ratio (α c), and prestressing force ratio (α ps). Among the two parameters related to prestressed strands, increasing the prestressing force ratio significantly reduces RDr , while the influence of the prestressed strand ratio on RDr is relatively small. On this basis, a matrix-based probabilistic predictive model for the residual drift ratio was established. According to various physical parameters, the proposed mathematical model accurately predicts the residual drift ratio and describes the influence of each parameter on it. Furthermore, an analytical resilience design approach was proposed, and an analytical expression in matrix form for a multi-parameter resilience design was derived. Lastly, the impact of parameters on the damage state was investigated, and the range of parameter values under investigation was established, according to the analytical resilience design approach. • The influence of parameters on residual drift was studied. Prestressing force and axial load ratio significantly impact. • A matrix-based probabilistic predictive model for the residual drift ratio was established. • An analytical resilience design approach was proposed, and the corresponding analytical expression was derived. • The range of parameters satisfying resilient design was determined. [ABSTRACT FROM AUTHOR]

As an effective measure to decrease the residual displacement under earthquakes, unbonded prestressed concrete (UBPRC) columns have been carefully investigated in previous research, while the influence of the complex characteristics of near-fault excitations on the residual displacement of UBPRC is less mentioned. This paper, therefore, focuses on the influence mechanism of the pulse effect and vertical effect of near-fault ground motions on the residual displacement of UBPRC columns. The residual displacement, at first, is formulated as a function of the coupled parameter T1-p (the ratio of the structural period to the pulse period). Then, the effect of near-fault vertical ground motion on the residual displacement is qualified based on the established mathematical model. Further, the model has been applied to investigate the effect of structural properties (dead load axial compression ratio, longitudinal reinforcement ratio, prestressing axial compression ratio, prestressing reinforcement ratio) on the residual displacement of UBPRC columns subjected to the joint action of horizontal and vertical ground motions. This research provides a quantitative methodology to quickly obtain the residual displacement spectra of the UBPRC columns under varying conditions combined with ground motion and structural parameters. [ABSTRACT FROM AUTHOR]