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A bandwidth optimization model for a novel equivalent 90° transmission-line section is proposed in this paper. Furthermore, the structure of 3-D compact 3-dB branch-line directional coupler and its equivalent-circuit model are presented. They can achieve both excellent isolations between each branch and high-density integration by using equivalent 90° transmission-line sections and coaxial through-silicon via technology in 3-D integrated circuits. Finally, a 3-D coupler is designed with the center frequency of 100 GHz, as well as the bandwidth and size reach 20 GHz and $174\times 236.9\times 208.7\,\,\mu \text{m}^{3}$ , respectively. The results of the 3-D full-wave field solver High-Frequency Structure Simulator and the proposed model are well matched, showing that the proposed model can be used to quickly evaluate the electrical performance of the 3-D coupler before manufacture, thus effectively promoting the design efficiency and quality.

In this paper, a broadband closed-form expression for the parasitic inductance of Through-X Vias (TXVs) with a frequency up to 100 GHz is proposed. The rigorous formulas related to the geometrical parameters are derived considering the proximity effect and the skin effect. The proposed model can accurately reflect the change in inductance caused by magnetic flux variation at high frequency. The inductance model is verified by comparing with the 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS) in whole frequency range considered. The proposed model and HFSS results show accordance with each other over large radius range, with a maximum error of 4.6%.

An on-site detection strategy is reported based on dual-color SiO2@quantum dot (QD)–integrated lateral flow immunoassay (LFA) strip to realize the quantitative and simultaneous detection of C-reactive protein (CRP) and procalcitonin (PCT) in serum. The dual-color SiO2@QD nanotags with monodispersity and excellent luminescence were synthesized using polyethyleneimine-mediated electrostatic adsorption of dense red CdSe/ZnS-COOH (excitation/emission 365/625 nm) or green CdSe/ZnS-COOH (excitation/emission 365/525 nm) QDs on the surface of 180 nm SiO2 spheres and were conjugated with anti-PCT and anti-CRP monoclonal antibodies, as stable and fluorescent-enhanced QD nanotags in the LFA system. The use of SiO2@QDs with two different fluorescent signals caused the sensitivity and specificity of the multiplex LFA system. As a result, the proposed assay provided a wide logarithmic determination range with a CRP quantitative range of 0.5–103 ng/mL and PCT quantitative range of 0.05–103 ng/mL. The limits of detection (LODs) of CRP and PCT reached 0.5 and 0.05 ng/mL, respectively. The SiO2@QD-based LFA showed great potential as rapid detection tool for the simultaneous monitoring of CRP and PCT in serum sample.

An analytic model of the tapered differential through glass vias is proposed in this paper. Each expression accounting for the via length, diameter, slope angle and pitch is derived from basic physics and the IMD layer is included, additionally. The RLGC equivalent circuit is verified by comparing the S-parameters resulted from the 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS) and Advanced Design System (ADS). The feature selective validation (FSV) technique is used to as a measure of the comparisons. The proposed model and HFSS results show accordance with each other up to 20 GHz The excellent transmission characteristics of glass substrate reflect from S-parameters, of which the S21 is about the order of magnitude of 10−3 dB and the S11 is lower than −30 dB till 20 GHz. Moreover, the impact of different configuration on transmission coefficient is investigated.

Malus sieversii(Ledeb.) M. Roem is a tertiary relict tree species and a rare and valuable resource for germplasm conservation. Since 1995, its wild forest has been severely destroyed by a devastating wood-boring beetle Agrilus mali Matsumura (Coleoptera: Buprestidae) in Xinjiang Uygur Autonomous Region, China. Where it invaded, this beetle infested more than 95% of the forests, and 80% of wild apple trees were reported dead in the hotspots. The physiological damage by A. mali infestation and their causality to tree death remain unclear. In this study, we attempted to explain the wild apple dieback from plant physiological perspectives, based on the hypothesis that the more damage M. sieversii suffered from the infestation of A. mali, the less water and fewer nutrients it could utilize. The study was conducted on trees with different extents of damage in wild apple forests over a large scale during 2016 and 2017. The stable carbon isotope ratio in leaves was analyzed to indicate tree water stress status. Total N, total P, total K, Ca2+ and Mg2+ were analyzed to reflect plant mineral nutrient status. The extent of damage was significantly associated with the leaf stable carbon isotope ratio in the drier year of 2016, but not significantly in 2017 with heavy rainfall in spring. The mineral nutrient contents of leaves were not significantly different among the four damage rankings in either year. The water stress experienced by M. sieversii was aggravated by the damage caused by A. mali, especially in a drought year, and indicates that the long-term water deficit caused by A. mali infestation may be the key factor leading to the decline of wild apple forests. The finding suggests the necessity of aerial irrigation for sustainable integrated pest management in wild apple trees.

A wideband equivalent-circuit model of coaxial-annular through-silicon vias (TSVs) for three-dimensional (3-D) integrated circuits is proposed in this paper. Rigorous closed-form formulas for the resistance and inductance of coaxial-annular TSVs are derived by computing the longitudinal electrical field in Cu and the longitudinal magnetic vector potentials in ${\rm{SiO}}_{2}$ and Si substrate with Bessel functions. The equivalent-circuit model can appropriately capture the skin effect in Cu as well as eddy-current effect in Si substrate. The proposed model is verified using 3-D full-wave field solver high frequency simulator structure, showing that it can yields highly accurate results up to 100 GHz.

The 3-D multistrata integration puts forward high requirements for signal integrity. The shielded-pair through-silicon vias (SPTSVs) proposed in this paper feature superior transmission properties and high jamming immunity suitable for differential-mode and common-mode transmission. Based on the quasi-static field theory, a wideband impedance model of SPTSVs considering the proximity effect, the line-to-line crosstalk, and the eddy current effect is derived. The parasitic parameters calculated by the impedance model are further given. The finite-element analysis shows that the proposed model highly agrees with the 3-D full-wave simulation and the analytical calculation. In addition, the characteristics of the impedance and the transmission coefficient are deeply analyzed with different design parameters. Finally, the impacts of the substrate effect and the metal–oxide–semiconductor effect on electrical characteristics of SPTSVs are revealed.

This paper presents an effective loop impedance extraction method and a model of a signal through-silicon via (TSV) surrounded by multiground TSVs. According to this method, the effective coupling substrate capacitances of multiground TSVs with different numbers and placements are calculated. Based on the calculated values of the resistance-inductance-capacitance-conductance (RLCG) parameters, the equivalent circuit and a two-port network model are established. The S -parameters of the model are validated by the simulated and measured results. Then, the effect of different patterns of ground TSVs on the central signal and coupling capacitance are discussed. Note that the hexagon pattern proposed in this paper can save the occupied area prominently without damaging the signal integrity.

This letter explores the inductance of interconnections including through-silicon vias (TSVs) and redistribution layers (RDLs) in 3-D stacked-chip packaging. It is described that the common summing method of partial inductances will result in some deviations from the full inductance. Then, the inductances of TSVs and RDLs are, respectively, calculated and are verified by a commercial electromagnetic simulator. The modified formulas are proposed for the more accurate full inductance model, which is derived from different design physical parameters of the interconnections. The side effect of a general summing method can be reduced a lot by our proposed analytical model.

The parasitic parameters and equivalent electrical model of differential dielectric-cavity through-silicon via (DDC-TSV) array on traditional low-resistivity silicon (LRSi) are proposed in this letter. TSV plugs are placed in the dielectric-cavity etched on LRSi. Each analytical formula in the model is established as the fuction of various physical geometries. The resistance–inductance–capacitance–conductance model and S-parameters of the DDC-TSV array are constructed by the Advanced Design System (ADS), which is verified by the 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS). Simulation results of the ADS and HFSS accord well with each other with frequencies up to 100 GHz, which shows good accuracy of the proposed model.

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 Fe3O4@Au magnetic nanoparticles (MNPs). Antibody-modified Fe3O4@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 Fe3O4@Au nanotags. After washing to remove impurities, Fe3O4@Au nanotags acted as high-performance SERS reporters for quantitative detection of the target in the LFA strip. Through this strategy, the proposed Fe3O4@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.

A physics based close form inductance model for three-dimensional (3-D) solenoid inductors with ground shileding is proposed in this letter. The expressions are derived in full consideration of partial self inductance and mutual inductance. The proposed model is extracted based on the process parameters and design parameters without any optimization. The 3-D inductor samples are fabricated on glass substrate by Through Glass Via (TGV) process. The accuracy of the proposed model is validated by comparing the results from the 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS) and measurement.

In this paper, a new model of the parasitic inductance using a glass core substrate is proposed. Based on the magnetic flux equation, the expressions are derived considering the different profiles of Through Glass Vias(TGVs). According to the skin effect, the magnetic flux density is solved as a frequency-varying parameter. The formulas can be used to calculate the self-partial inductance and mutual-partial inductance. The inductance model is verified by comparing with the results of 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS). The proposed model and HFSS results show accordance with each other up to 100 GHz.

The three-dimensional integrated circuits (3D ICs) based on through silicon via (TSV) technology offer a solution to meet the continuously increasing demand on high-speed electronic products. In order to comprehensively evaluate the signal transmission of TSV in increasing signal frequency, accuracy equivalent circuit model is necessary. In this paper, a method of double-T type equivalent circuit modelling for TSVs is proposed and applied to coaxial TSV and ground-signal (GS)-type TSVs. Furthermore, the transmission parameters (S21) of the double-T models are evaluated by SPICE and compared with the results of 3-D full-wave electromagnetic field simulation (HFSS). The good accordance of the results up to 50GHz verifies the accuracy of the proposed method.

The polymer-cavity through-silicon vias (TSVs) on low resistivity silicon (LRSi) are proposed in this letter to reduce the conductive substrate losses for microwave applications, due to that the coupling loss of conventional LRSi is considerable in high speed three-dimensional integrated circuits (3-D ICs). The accurate wideband equivalent circuit model and simplified π-model are derived based on the physical design parameters, which are established by the ADS software. Well agreements between the proposed models and 3D full-wave EM field simulation of Ansoft's HFSS are shown with the operating frequencies up to 20 GHz.

A simple formula for the internal impedance of mixed carbon nanotube (CNT) bundles is proposed in this paper. It can appropriately capture the skin effect as well as temperature effect of mixed CNT bundles. The computing time and results of the simple formula and the numerical calculation are compared with various mean diameters, standard deviations, and temperatures. It is shown that the proposed simple formula can improve the efficiency dramatically, and has very high accuracy in the whole frequency range considered, with maximum errors of 1.2% and 2.5% for the resistance and the internal inductance, respectively.

Since the coupling loss of conventional low resistivity silicon (LRSi) is considerable in high speed three-dimensional integrated circuits (3-D ICs), air-cavity through-silicon vias (TSVs) on LRSi are proposed in this letter to reduce the conductive substrate losses for microwave applications. The $Q$ -factor and insertion loss are exploited to assess the effect of air-cavity TSVs. The accurate wideband equivalent circuit model and simplified $\pi$ -model are derived based on the physical design parameters, which are established by the ADS software. Well agreements between the proposed models and 3-D full-wave EM field simulation of Ansoft's HFSS are shown with the operating frequencies up to 20 GHz.

In this paper, ground-signal-ground type through-silicon vias (TSVs) exploiting air gaps as insulation layers are designed, analyzed and simulated for applications in millimeter wave. The compact wideband equivalent-circuit model and passive elements (RLGC) parameters based on the physical parameters are presented with the frequency up to 100 GHz. The parasitic capacitance of TSVs can be approximated as the dielectric capacitance of air gaps when the thickness of air gaps is greater than 0.75 μm. Therefore, the applied voltage of TSVs only needs to achieve the flatband voltage, and there is no need to indicate the threshold voltage. This is due to the small permittivity of air gaps. The proposed model shows good agreement with the simulation results of ADS and Ansoft's HFSS over a wide frequency range.

Premise of the study: The One Thousand Plant Transcriptomes Project (1KP, 1000+ assembled plant transcriptomes) provides an enormous resource for developing microsatellite loci across the plant tree of life. We developed loci from these transcriptomes and tested their utility. Methods and Results: Using software packages and custom scripts, we identified microsatellite loci in 1KP transcriptomes. We assessed the potential for cross-amplification and whether loci were biased toward exons, as compared to markers derived from genomic DNA. We characterized over 5.7 million simple sequence repeat (SSR) loci from 1334 plant transcriptomes. Eighteen percent of loci substantially overlapped with open reading frames (ORFs), and electronic PCR revealed that over half the loci would amplify successfully in conspecific taxa. Transcriptomic SSRs were approximately three times more likely to map to translated regions than genomic SSRs. Conclusions: We believe microsatellites still have a place in the genomic age—they r...

We demonstrate coherent control of population transfer between vibrational states in an optical lattice by using interference between a one-phonon transition at $2\omega$ and a two-phonon transition at $\omega$. The $\omega$ and $2\omega$ transitions are driven by phase- and amplitude-modulation of the lattice laser beams, respectively. By varying the relative phase between these two pathways, we control the branching ratio of transitions to the first excited state and to the higher states. Our best result shows an improvement of the branching ratio by a factor of 3.5$\pm$0.7. Such quantum control techniques may find broad application in suppressing leakage errors in a variety of quantum information architectures., Comment: 5 pages, 4 figures