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OBJECTIVE: To investigate the effects of parecoxib on postoperative cognitive dysfunction, and serum levels of neuron-specific enolase (NSE) and S100β protein (S100β) in elderly patients undergoing surgery. PATIENTS AND METHODS: The retrospective cohort study method was used to collect the clinical data of 94 elderly patients who underwent elective orthopedic and general anesthesia surgery in our hospital from September 2020 to February 2022. 94 patients were divided into the control group (47 cases) and the study group (47 cases), according to different intervention methods. In the study group, 40 mg of parecoxib was injected intravenously into patients 30 min before the induction of anesthesia, and the patients in the control group were given the same dose of normal saline intravenously before the operation. The basic clinical data of the patients were collected. The levels of the indexes before operation and 6 hours after operation were compared between the two groups, including the Montreal Cognitive Scale (MoCA) score, inflammatory factor indicators [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), interleukin-10 (IL-10), interleukin-1β (IL-1β), monocyte chemokine-1 (MCP-1), and inducible nitric oxide synthase (iNOS)], serum cortisol (CORT), beta-amyloid (β-AP), adiponectin (ADP), NSE, and S100β. RESULTS: No significant differences in the preoperative MoCA score, TNF-α, IL-6, CRP, IL-10, IL-1β, MCP-1, iNOS, CORT, β-AP, ADP, NSE, and S100β levels were observed between the two groups (p>0.05). The postoperative MoCA score in the study group was significantly higher than that in the control group (p<0.05). The postoperative levels of TNF-α, IL-6, CRP and IL-1β in the study group were significantly lower than those in the control group (p<0.05), and the postoperative levels of IL-10, MCP-1 and iNOS in the study group were significantly higher than those in the control group (p<0.05). CONCLUSIONS: Parecoxib can notably inhibit the levels of postoperative inflammatory cytokines, improve neurological dysfunction, and reduce the occurrence of postoperative cognitive dysfunction in patients. The contents of serum NSE and S100β have potential value in the diagnosis of postoperative cognitive dysfunction in elderly patients. [ABSTRACT FROM AUTHOR]

A phase field model is developed to study the flexoelectricity in nanoscale solid dielectrics, which exhibit both structural and elastic inhomogeneity. The model is established for an elastic homogeneous system by taking into consideration all the important non-local interactions, such as electrostatic, elastic, polarization gradient, as well as flexoelectric terms. The model is then extended to simulate a two-phase system with strong elastic inhomogeneity. Both the microscopic domain structures and the macroscopic effective piezoelectricity are thoroughly studied using the proposed model. The results obtained show that the largest flexoelectric induced polarization exists at the interface between the matrix and the inclusion. The effective piezoelectricity is greatly influenced by the inclusion size, volume fraction, elastic stiffness, and the applied stress. The established model in the present study can provide a fundamental framework for computational study of flexoelectricity in nanoscale solid dielectrics, since various boundary conditions can be easily incorporated into the phase field model. [ABSTRACT FROM AUTHOR]

The article focuses on a study which aims to investigate prevalence of reactivation of human polyomavirus John Cunningham virus (JCV) in patients with systemic lupus erythematosus (SLE) and associated clinical manifestations. It states that the prevalence of JACV viruria and urine JCV viral load were higher in patients with SLE. It mentions that JCV viruria and urine JCV viral load were associated with occurrence of arthritis/arthralgia in patients with SLE.

A new type of rat-race coupler, based on electromagnetic bandgap (EBG)-loaded half-mode substrate integrated waveguide (HMSIW) and composite right/left-handed (CRLH) HMSIW, has been proposed and investigated comprehensively. It consists of three sections of EBG-loaded HMSIWs with 90° phase delay and one section of CRLH HMSIW with −90° phase advance. Due to the evanescent-mode of EBG-loaded HMSIW and the backward behavior of the CRLH HMSIW in the left-handed region, the size of such a miniaturized rat-race coupler is reduced about 65.7% in comparison with its conventional counterpart. The rat-race coupler with the central frequency of 5.5 GHz has been designed and fabricated so as to validate our method, and its good performance is demonstrated by both simulated and measured results. [ABSTRACT FROM AUTHOR]

This paper presents an effective technique to obtain miniaturized and high-selectivity sub-strate integrated waveguide (SIW) bandpass filters by loading complementary split-ring res-onators (CSRRs) at the SIW cavities. The existence of the CSRR enables a considerable reduction of the resonance frequency of a conventional SIW cavity thanks to the coupling effect between CSRR and SIW cavity. Besides, a sharp roll-off is generated in a higher stopband due to the characteristics of CSRRs. To demonstrate the operation principal, the second- and third-order SIW bandpass filters are fabricated using standard printed circuit board technology, showing advantages of compact size, good selectivity, easy fabrication, and integration with other circuits. The measured ¿'-parameters agree well with the simu-lated ones. [ABSTRACT FROM AUTHOR]

An efficient and stable hybrid method, based on the time-domain integral equation (TDIE) and time-domain physical optics (TDPO), is developed for investigating transient radiation and scattering from perfectly electrical conducting (PEC) objects. It at first requires partitioning the PEC object surface into TDIE and TDPO regions, respectively. Then, a set of hybrid TDIE-TDPO equations is derived and solved using an adaptive marching-on-in- degree (MOD) method. The fast Fourier transforms (FFT)-based blocking scheme is further implemented into the proposed algorithm so as to reduce NDue to image rights restrictions, multiple line equation(s) cannot be graphically displayed dependence of the traditional MOD method to NO log² (NO), where NO is the highest order of the weighted Laguerre polynomials used for computation. Under such circumstances, its computational cost, in comparison with the full TDIE-MOD solver, is reduced significantly. Several numerical examples are presented to demonstrate its accuracy and efficiency in solving some typical transient electromagnetic problems. [ABSTRACT FROM AUTHOR]

One novel dielectric conformal finite-difference time-domain (FDTD) method is used for computing specific absorption rate (SAR) distribution over the human body model in one metallic cabin with some windows on its wall. It is based on the concept of area average, which is different from other traditional conformal FDTD schemes. Our developed algorithm is verified by calculating both point and average SARs of dielectric sphere and human head models illuminated by an intentional electromagnetic pulse (IEMP), respectively, and CST Microwave Studio (MWS) also used for validating its accuracy. Numerical calculations are further performed to show the average SAR distribution over the human body model for different IEMP incidences, where the cabin door is opened or closed. The effects of E-field amplitude, direction and polarization of the incident IEMP on the SAR distributions are characterized in detail. This study will be useful for further electromagnetic protection for some persons working in high power exposure environment. [ABSTRACT FROM AUTHOR]

Summary Abnormal Ca2+-mediated signalling contributes to the pathogenesis of rheumatoid arthritis (RA). However, the potential implication of calcium channel blocker in RA remained unknown. We hypothesized that nifedipine, an L-type calcium channel blocker, combined with a calcineurin inhibitor, could suppress T cell activation via targeting different level of the Ca2+ signalling pathway. The percentage of activated T cells and the apoptotic rate of mononuclear cells (MNCs) was measured by flow cytometry. The MNC viability, cytokine production, cytosolic Ca2+ level and activity of the nuclear factor of activated T cells (NFAT) were measured by enzyme-linked immunosorbent assay (ELISA). The NFAT-regulated gene expression, including interleukin (IL)-2, interferon (IFN)-γ and granulocyte-macrophage colony-stimulating factor (GM-CSF), was measured by real-time polymerase chain reaction (PCR). We found that the percentage of activated T cells in anti-CD3 + anti-CD28-activated MNC was higher in RA patients. High doses of nifedipine (50 µM) increased MNCs apoptosis, inhibited T cell activation and decreased T helper type 2 (Th1) (IFN-γ)/Th2 (IL-10) cytokine production in both groups. The Ca2+ influx was lower in anti-CD3 + anti-CD28-activated MNC from RA patients than healthy volunteers and suppressed by nifedipine. When combined with a subtherapeutic dose (50 ng/ml) of cyclosporin, 1 µM nifedipine suppressed the percentage of activated T cells in both groups. Moreover, this combination suppressed more IFN-γ secretion and NFAT-regulated gene (GM-CSF and IFN-γ) expression in RA-MNCs than normal MNCs via decreasing the activity of NFATc1. In conclusion, we found that L-type Ca2+ channel blockers and subtherapeutic doses of cyclosporin act additively to suppress the Ca2+-calcineurin-NFAT signalling pathway, leading to inhibition of T cell activity. We propose that this combination may become a potential treatment of RA. [ABSTRACT FROM AUTHOR]

A broadband dual-polarized four-port (DPFP) antenna is presented in this paper, which consists of a radiation element and a feed network. It is very compact in size, with the diameter of 150.0mm and the height of 47.0mm, with the following unique properties: (1) it has hybrid beam-forming capability and operates at two modes, which depends on its excitation; (2) its operating frequency range is from 0.96 to1.78GHz, and the return loss is about 10 dB; (3) its insertion loss is (3 ± 0.5) dB, with its balanced power splitting over the relative bandwidths of 37% at Mode 1 (180° ± 5° phase shifting) and 55% at Mode 2 (±5° phase shifting), respectively; (4) an isolation of 30 dB at Mode 1 is obtained between the dual polarized ports, with the gain of 7.6 dBi and 42° of the 3 dB-bandwidth at 1.25GHz; and (5) the gain di?erence between Modes 1 and 2 is about 7 dB, within the angle of -15° ≤ θ ≤ 15° for the same polarization at 1.25GHz. For the application of DPFP, a hybrid beam forming algorithm is proposed with an angular precision of 7° and is validated by measurement. [ABSTRACT FROM AUTHOR]

A novel compact branch-line coupler operating in two arbitrary frequencies is proposed, analyzed and designed. Stepped-impedance stubs are used in the branch-line coupler to achieve dual-band applications. Parameters of the structure are chosen and provided for design guidelines. Broader operating frequency ratios and compactness are achievable. For the purpose of validation, a microstrip coupler operating at 2.4/5.2GHz is fabricated and measured. [ABSTRACT FROM AUTHOR]

An efficient hybrid method, based on time-domain integral equation (TDIE) and time-domain physical optics (TDPO), is proposed for studying on transient electromagnetic responses of some wire and surface structures illuminated by an electromagnetic pulse (EMP), respectively. Two groups of triangular-type basis functions are used to expand the currents on both of them. The derived hybrid TDIE-TDPO equations are solved by marching-on-in-time (MOT) scheme. In comparison with the full TDIE-based MOT method, computational complexity of our developed method is reduced significantly, and at the same time, with high accuracy maintained. Numerical results of EMP responses of some typical wire and surface structures are presented to demonstrate its versatility, accuracy and efficiency, with proximity effects between them captured and discussed. [ABSTRACT FROM AUTHOR]

A compact microstrip rat-race coupler is proposed with a new phase inverter which is realized by a modified Lange coupling structure with a slotted ground plane and a floating-potential conductor. Based on the even- and odd-mode theory, its parameters are generally synthesized. In order to further miniaturize the rat-race coupler, a T-shaped line is utilized. A prototype operating at 2.0 GHz is designed and fabricated for verification. The circumference of our proposed rat-race coupler is only 0.52λ. Its in-phase and out-of-phase bandwidths are also enhanced, with reasonable agreement obtained between its simulated and measured S-parameters. [ABSTRACT FROM AUTHOR]

Electrothermal effects in various through silicon via (TSV) arrays are investigated in this paper. An equivalent lumped-element circuit model of a TSV pair is derived. The temperature-dependent TSV capacitance, silicon substrate capacitance and conductance are examined for low-, medium-, and high-resistivity silicon substrates, respectively. The partial-element equivalent-circuit (PEEC) method is employed for calculating per-unit-length (p.u.l.) resistance, inductance, insertion loss and characteristic impedances of copper and polycrystalline silicon (poly-Si) TSV arrays, and their frequency-and temperature-dependent characteristics are treated rigorously. The modified time-domain finite-element method (TD-FEM), in the presence of a set of periodic differential-mode voltage pulses, is also employed for studying transient electrothermal responses of 4-and 5-TSV arrays made of different materials, with their maximum temperatures and thermal crosstalk characterized thoroughly. [ABSTRACT FROM AUTHOR]

A compact dual-band bandpass filter is proposed using asymmetrical dual stepped-impedance stub-loaded open-loop resonators, where additional transmission zeros are introduced so as to improve its upper rejection. Its mode characteristics and generation of its transmission zeros are analyzed theoretically. In such a filter, double resonators have different configurations, with their individual transmission zeros generated at different frequencies. It is demonstrated that the realized filter has good performance in frequency selectivity and spurious suppression. Also, good agreement is obtained between its simulated and measured S-parameters. Its -20 dB upper stopband is improved up to 2.57 times of the first central frequency, which is much better than its previous dual-band counterparts with small frequency ratios. [ABSTRACT FROM AUTHOR]

A compact substrate integrated waveguide (SIW) transversal filter using microstrip dual-mode resonator is proposed, with its coupling scheme given to predict its desired performance. The microstrip dual-mode resonator is introduced to achieve compact size, which is etched on the top metal layer of the SIW cavity. An additional transmission zero, contributed by bypass coupling due to the higher order mode of SIW cavity, is used to suppress its first spurious passband. A filter sample was fabricated using standard printed circuit board (PCB) technology, with good agreements obtained between its measured and simulated S-parameters. [ABSTRACT FROM AUTHOR]

Large-scale submicron gallium oxide hydrate (GaOOH) rods have been synthesized by a simple hydrothermal process and their optical, electrochemical properties have been analyzed. The diameter of the GaOOH nanorods with good single crystalline structure is 80-800 nm and length of less than 4 μm. The tips of the GaOOH structures are composed of nanorods with the diameter of less than 10 nm and length of more than 100 nm. Hydrothermal temperature, time and the Ga-contained starting materials have important roles on the formation and growth of submicron GaOOH rods. The submicron GaOOH rods exhibit good UV-vis absorption ability. The electrochemical analysis shows that the submicron GaOOH rods have good detecting ability for ascorbic acid and cysteine in PBS and NaCl solution exhibiting promising potential for electrochemical sensing application. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Two microstrip tri-section filters with mixed couplings are presented, respectively. The location of the additional transmission zero can be adjusted by changing the nature of direct couplings. Inter-digital coupling structure and defected ground structure (DGS) are adopted to miniaturize their geometries. Wide stopband is obtained in each of them because of the suppression of the first spurious passband. The measured S-parameters of the realized filters agree well with the simulated results, with their high performance demonstrated. [ABSTRACT FROM AUTHOR]

A novel third-order substrate integrated waveguide (SIW) filter incorporated with a coplanar waveguide (CPW) is presented in this paper. The CPW not only acts as a resonator, but also brings mixed coupling between two SIW resonators. It is shown that the filter has two transmission zeros and wide stopband, which is very compact in comparison with conventional third-order SIW counterpart. Good agreement is obtained between its measured and simulated S-parameters. [ABSTRACT FROM AUTHOR]

The structure, hydrogen storage property, and electrochemical characteristics of the La0.7Mg0.3Ni5.5-x (Al0.5Mo0.5)x (x = 0, 0.2, 0.4, 0.6, 0.8) hydrogen storage alloys have been investigated systematically. It has been found by X-ray powder diffraction and Rietveld analysis that the alloys are multiphase and consist of impurity Ni phase and two main crystallographic phases, namely, the La(La, Mg)2Ni9 phase and the LaNi5 phase, and the lattice parameters and the cell volumes of both the La(La, Mg)2Ni9 phase and the LaNi5 phase increase with increasing Al and Mo content in the alloys. The P-C isotherm curves indicated that the hydrogen storage capacity of the alloy first increases and then decreases with increasing x, and the equilibrium pressure decreases with increasing x. The electrochemical measurements show that the maximum discharge capacity first increases from 298.5 (x = 0) to 328.3 mAh/g (x = 0.6) and then decreases to 304.7 mAh/g (x = 0.8). The high rate dischargeability (HRD) of the alloy electrodes increases lineally from 65.4 pct (x = 0) to 86.6 pct (x = 0.8) at the discharge current density of 1200 mA/g. Moreover, the exchange current density of the alloy electrodes also increases monotonously with increasing x by the linear polarization curves. The hydrogen diffusion coefficient in the alloy bulk, D, increases with increasing Al and Mo content and thus enhances the low-temperature dischargeability (LTD) of the alloy electrodes. [ABSTRACT FROM AUTHOR]

The solanum fruit fly,Bactrocera latifrons(Hendel), is a major agricultural pest in Asia and Hawaii, and it is important to prevent its widespread invasion in plant quarantine. In this study we introduced a real-time polymerase chain reaction (PCR) essay, using SYBR Green I dye, to rapidly identifyB. latifronson an ABI PRISM 7700 sequence detection system. A latifron-specific PCR primer set was obtained based on mtDNA COI gene ofB. latifrons. NineBactrocerafruit flies,B. latifrons,Bactrocera dorsalis,Bactrocera papayae,Bactrocera carambolae,Bactrocera philippinensis,Bactrocera occipitalis,Bactrocera correcta,Bactrocera cucurbitaeandBactrocera tau, were used to determine the specificity of primers lati1 and lati2. A series of genomic DNA dilutions ofB. latifrons(0.01, 0.1, 1, 10, 20, 40 and 100 ng) were used to assess the sensitivity of the SYBR Green PCR. Template DNA concentration was one of the sources of variability in cycle threshold values (CT) and the optimum DNA concentration was between 1 and 20 ng. Genomic DNA isolated from larvae, pupae and adult specimens ofB. latifronswere used to assess the specificity of the SYBR Green PCR. Melting curve analysis and agarose gel electrophoresis was employed to check the specificity of PCR products. Similar amplification plots were obtained using DNA from the three different stages ofB. latifronswith primer set lati1/lati2. The melting temperature (Tm) of PCR products was 77.5 ± 0.1°C, and the length of the amplified fragment 366 bp. Given the specificity and sensitivity of the assay, combined with high speed, low cost and the possibility of automating, SYBR Green PCR can be used as a rapid and specific technique for pest species identification in plant quarantine. [ABSTRACT FROM AUTHOR]

The wideband average power handling capabilities (APHC) of coupled microstrips on a single-layer polyimide substrate and also on a polyimide and GaAs double-layer substrate are studied. Since the thermal conductivity of polyimide materials is only about 0.2 W/m °C, the APHC of the coupled microstrips is severely limited by the polyimide thickness. As a first step to obtaining the APHC, the ohmic and dielectric losses of even and odd modes need to be calculated. The rise in temperature is determined using a proposed thermal model in which the lateral heat dissipation on the neighbouring microstrips is appropriately treated. Numerical results are presented to show the effects of microstrip conductivity and thickness, and polyimide thickness on the APHC for different coupled microstrip configurations. Several ways to effectively enhance the APHC are suggested, which could be useful in the design of coupled microstrips on, or embedded in, polyimides. [ABSTRACT FROM AUTHOR]

The attenuation and slow-wave characteristics in an inverted embedded metal-insulator-semiconductor (IEM-MIS) microstrip line are investigated in this paper, based on the extracted frequency-dependent distributed parameters, that is, per-unit-length series resistance and inductance, shunt capacitance, and conductance of the structure. Parametric studies are performed to show the combined effects of different parameters, such as strip thickness, width, conductivity, embedding depth, and silicon conductivity and its thickness, on the mode attenuation constant and slow-wave factor (SWF). © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 366–369, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20143 [ABSTRACT FROM AUTHOR]

We present a wide-band experimental, characterization of an on-chip shunt inductor and capacitor (LC) interconnect. (A previous paper by the authors considered the series LC case). In order to capture the effects of patasitic parameters on the wide-band transmission and reflection characteristics of shunt LC interconnects, we propose a generalized frequency-independent circuit model for fast-running simulations. The model is accurate to above its second resonant frequency, with low average simulation errors for both reflection and transmission coefficients compared to the measured two-port S parameters over the frequency range of 1 to 14 GHz. [ABSTRACT FROM AUTHOR]

A statistical description of the global performance of on-chip spiral inductors, based on extensive measurement is presented. These inductors were fabricated with different turn numbers or track lengths/track widths, but with the same spacing. From the S parameters measured using a de-embedding technique, the inductance L, Q factor, self-resonance frequency, and figure-of-merit indicator (FMI) of these inductors are determined. Various local scalable formulas are obtained in order to describe the features of these inductors. Based on extensive parametric studies, certain ways to improve these inductor performances can be found. © 2004 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14, 111–121, 2004. [ABSTRACT FROM AUTHOR]

Extensive experimental results and detailed investigations of the performance of on-chip circular double-spiral stacked inductors on silicon substrates are presented. Based on a proposed equivalent circuit model and measured S-parameters using the de-embedding technique, the inductance L, resonant frequency ƒ[subres], Q-factor, coupling capacitance between the upper and lower spirals, and oxide capacitance of these inductors are extracted and compared with the single-spiral case. Some locally scalable formulas, including single-spiral geometries, are obtained to predict inductor performance. Methods to improve the L and Q-factor are explored for double-spiral stacked inductors with single via connection. [ABSTRACT FROM AUTHOR]

The effects of dielectric, radiative leakage and ohmic losses in CPWs on the propagation of Gaussian and sinusoidally modulated Gaussian pulses are investigated. These CPWs are assumed to be fabricated on a single-layer low-temperature co-fired ceramic (LTCC) substrate. It is shown that, based on the improved empirical formula for accurate prediction of the ohmic attenuation constant presented by Liao et al., the lossy effects in LTCC CPWs are dominated by the ohmic loss of the center and ground conductive planes in the frequency range up to 40 GHz. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 94–97, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11137 [ABSTRACT FROM AUTHOR]

The distortion of pulse waves propagating in some shielded composite ferrite microstrip transmission lines (FMTLs) is studied in this paper. The mathematical treatment is based on the Galerkin’s method in the spectral domain and the fast Fourier transformation (FFT). The hybrid effects of the biasing magnetic dc field intensity and its orientation on the pulse wave distortion are examined and compared. It is shown that the pulse distortion can be effectively reduced by changing the biasing field intensity or orientation. [ABSTRACT FROM AUTHOR]

The effect of anisotropy in multilayer superstrate-substrates on the propagation of a Gaussian pulse and a sinusoidally modulated Gaussian pulse in shielded microstrip lines (MLs) has been examined. Such multilayer superstrate-substrates are made of sapphire, ferrite and perhaps biaxially anisotropic materials, characterised by both tensorial permittivity and permeability. Mathematical treatments used were based on Galerkin's method in the spectral domain and fast Fourier transformation (FFT). Parametric studies were performed to show the effects of various diverse anisotropic occurrences in the superstrate-substrates on pulse distortion, including time delay, ringing and crosstalk between signal and sensing strips. It was shown that pulse distortion could be reduced effectively by combining different anisotropies in superstrates and substrates. [ABSTRACT FROM AUTHOR]

The dispersion characteristics of the dominant mode in V-shaped microstrip lines are investigated using the finite-difference time-domain (FDTD) method. Such V-shaped microstrip lines are assumed to be fabricated on a single-layer isotropic substrate. The hybrid effects of the inclined angle of the metal wall and the permittivity of the filling material on the effective permittivity and characteristic impedance are examined and compared. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 320–323, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11049 [ABSTRACT FROM AUTHOR]

Deals with a study which examined the inductances, Q factors, and resonance frequencies of on-chip square, single-level (SL) and double-level (DL) inductors on silicon substrates. Description of SL and DL square inductors; Inductor models; Experimental and simulation results; Conclusions.

A compact lumped-element equivalent circuit model of two-layer integrated spiral inductors on silicon substrates is developed in this article. Based on this proposed model, excellent agreements are achieved between the measured and simulated S-parameters for different inductors. Also, both self- and mutual inductances of two-layer inductors are accurately extracted, and their overall performances are understood clearly. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13: 148–153, 2003. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the resonant scattering characteristics of slit coupled cylindrically eccentric impedance cavity. Methodology; Results of the study.