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To evaluate outcomes following percutaneous vertebroplasty with high viscosity cement (PVP-HVC) and percutaneous kyphoplasty (PKP) with normal-viscosity cement in patients with osteoporotic vertebral compression fractures (OVCFs).Pertinent studies were retrieved by searching five electronic databases up to July 2021. Additional records were identified via hand-searching of related references. Risk ratio (RR) and weighted mean difference (WMD), with their 95% confidence intervals (CIs), were calculated. A trial sequential analysis (TSA) was done for cement leakage.Twelve studies, embracing 1050 patients with OVCFs, were included. PVP-HVC was superior to PKP with normal-viscosity cement regarding risk of cement leakage (RR: 0.67, 95% CI: 0.54-0.83, IPVP-HVC and PKP with normal-viscosity cement are safe and effective treatments for the management of OVCF, but the former is superior to the latter in terms of procedure time. The potential of PVP-HVC in reducing cement leaks remains to be validated by more well-designed studies.

A novel antenna with the combination of the shorted-edge patch and the coupling feed is proposed in this letter. This new combination still keeps the good features of patch antenna, such as low cost and easy integration. Moreover, it simultaneously possesses several useful features: low cross polarization, wideband, high gain, and adjustable beamwidth in design. To show the effectiveness, a prototype operating at the central frequency of 12.5 GHz is designed and measured. Good agreement between the simulated and measured results has been obtained. The gain and the cross-polarized level are 11.2 dBi and −40 dB, respectively, and the bandwidth is 35%.

Aim. This study is aimed at constructing the competing endogenous RNA (ceRNA) network in chromophobe renal cell carcinoma (ChRCC). Methods. Clinical and RNA sequence profiles of patients with ChRCC, including messenger RNAs (mRNAs), microRNAs (miRNAs), and long noncoding RNAs (lncRNAs), were obtained from The Cancer Genome Atlas (TCGA) database. “edgeR” and “clusterProfiler” packages were utilized to obtain the expression matrices of differential RNAs (DERNAs) and to conduct gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Weighted gene coexpression network analysis (WGCNA) was performed to screen the highly related RNAs, and miRcode, StarBase, miRTarBase, miRDB, and TargetScan datasets were used to predict the connections between them. Univariate and multivariate Cox proportional hazards regressions were performed in turn to elucidate prognosis-related mRNAs in order to construct the ceRNA regulatory network. Results. A total of 1628 DElncRNAs, 104 DEmiRNAs, and 2619 DEmRNAs were identified. WGCNA showed significant correlation in 1534 DElncRNAs, 98 DEmiRNAs, and 2543 DEmRNAs, which were related to ChRCC. Fourteen DEmiRNAs, 113 DElncRNAs, and 43 DEmRNAs were screened. Nine mRNAs (ALPL, ARHGAP29, CADM2, KIT, KLRD1, MYBL1, PSD3, SFRP1, and SLC7A11) significantly contributed to the overall survival (OS) of patients with ChRCC ( P < 0.05 ). Furthermore, two mRNAs (CADM2 and SFRP1) appeared to be independent risk factors for ChRCC. Conclusion. The findings revealed the molecular mechanism of ChRCC and potential therapeutic targets for the disease.

Antibiotics have played an important role in the prevention and treatment of human and animal diseases as well as the improvement of animal products. However, the mass products and application of antibiotics, especially the abuse in animal industry and clinical medicine, led to the widespread of antibiotic resistance genes (ARGs) in the environment. They spread widely through conjugation, transposition, and transformation with the help of movable elements such as plasmid, transposon and integrons, resulting in the continuous enhancement of microbial medicinal properties and posing a serious threat to human health and ecological security. At present, great attention has been paid to the impacts of ARGs on human health, but limited research on the ecological risk of ARGs in the environment. Here, the status quo and ecological risks of ARGs pollution were summarized, and the future research priorities in this field were prospected. We hope it could pave the way for further studies and give references for the ecological control and prevention of ARGs pollution.自抗生素被发现和使用以来,其在人类和动物疾病预防与治疗、提高动物生产等方面均发挥了重要作用。但抗生素的批量生产及大量应用,特别是在养殖业和临床医疗上的滥用,导致抗生素抗性基因(ARGs)在环境中普遍存在,其借助质粒、转座子、整合子等可移动元件通过接合、转座、转化等方式在环境中广泛传播,导致微生物药性不断增强,对人类健康和生态安全造成严重威胁。当前,ARGs对人类健康的影响已受到高度关注,但有关ARGs在环境中的生态风险研究还相对薄弱。本文综述了ARGs污染的现状及其生态风险,并对该领域中未来研究重点进行了展望,以期为今后抗性基因的研究和生态防控提供参考。.

Single-sideband time-modulated phased array (STMPA) provides beam-scanning capability and eliminates some undesired sidebands. To further improve the frequency spectrum, the time modulator of the STMPA with S -step waveform for better eliminating the undesired sidebands and widening the allowable signal bandwidth without aliasing is proposed in this letter. The S -step waveform is realized by digital attenuators in time modulators. Most of sidebands are eliminated and the allowable signal bandwidth becomes 4 S times as wide as that of conventional time-modulated array (TMA). The general expressions of the sideband level (SBL) and the theoretical loss of the time modulator related to the number S of the steps are given. To experimentally verify the feasibility of the proposed design, the time modulator with four-step waveform and the corresponding four-element STMPA are fabricated and measured.

Vaporized samarium (Sm) has been released in the ionosphere for artificially creating plasma clouds, which may be tailored as radio wave reflectors for over-the-horizon communications. The model of samarium releases needs to be further refined for filling the gap between experimental observations and theoretical simulations. A sophisticated simulation model, so far to date, for samarium release in the ionosphere has been developed, and the redundancy reaction, inversion, and the photochemical reactions are all taken into account. The model results are consistent with experimental observations. Due to the geomagnetic field and neutral wind, the shape of artificial plasma clouds significantly changes. The error of the spherically symmetric reflection model is large. According to the density distribution of plasma clouds, the geometric theory of diffraction (GTD) is introduced here to deal with the electromagnetic scattering. The GTD-based scattering model has been established and used to study the time–space evolution of the ground-received power patterns in this article.

This article presents an enhanced single-sideband time-modulated phased array (ESTMPA) using modulating pulses with stepped waveforms. Based on the in-phase/quadrature (I/Q) complex modulation technique, this phase-only weighting array generates a scanning beam at the 1st sideband. The proposed modulating pulses realized through a reconfigurable power divider in I/Q time modulator can avoid the power loss from the switches during switch-OFF state and eliminate the maximum undesired sideband—the 5th harmonic in STMPA. As a result, it brings a power spectrum with less undesired sidebands, lower sideband level (−16.9 dB), higher harmonic efficiency (94.96%), and wider allowable signal bandwidth (eight times as wide as that of the conventional time modulated array). To experimentally verify the feasibility of the proposed design, a wideband enhanced I/Q time modulator and its corresponding eight-element ESTMPA are designed and manufactured. A detailed study on the effect of the magnitude and phase deviations in the circuit and the transition period of modulating pulse are presented. The measured results of power spectrum and radiation pattern have a good agreement with the simulated ones.

Wide band gap devices enable motor inverter to work at very high switching frequency. Increased switching frequency will significantly improve the control performance of the high speed permanent magnet synchronous machine (HSPMSM). However, in order to keep the low cost of the whole system, in many cases, the micro controller (MCU) used for motor control has limited performance, and the control frequency can not follow the increased switching frequency. In order to improve the control performance of HSPMSM with a low cost MCU, a novel low control frequency current control strategy for HSPMSM is proposed in this paper. The proposed strategy changes the PWM duty ratio of each half switching period to make the inverter’s output voltage as closer to the reference voltage as possible. Through proposed strategy, the high switching frequency is fully utilized at low control frequency and the similar current steady state control effect as when using high control frequency is achieved. Relevant simulations are carried out to validate the proposed control strategy.

Stress is the non-specific systemic response that occurs when the body is stimulated by various factors, and it can affect multiple systems of the body. Recent studies have shown that gut microbiota is an essential part of human microecology, and plays a pivotal role in keeping the body healthy. Stress can result in gut dysbiosis by affecting the function of intestinal mucosal barrier, intestinal immune and gastrointestinal motility. This article reviewed the alteration of gut microbiota caused by stress and the possible mechanisms involved.

A low-profile differentially fed microstrip patch antenna with broad impedance bandwidth is proposed by incorporating a resonant mode of the slot into TM10 and TM12 modes of the patch resonator. Initially, the shorting pins are symmetrically placed underneath the patch so as to push up the resonant frequency of TM10 mode in proximity to that of TM12 mode ( f 12). After that, the central slot could be employed to excite an additional mode resonating closely to the f 12 by increasing the slot length. Additionally, a pair of small circular disks is introduced below the radiating patch for good impedance matching. Finally, the wideband antenna is fabricated and measured to validate the predicted performance. The results illustrate that the antenna has gained a broad impedance bandwidth of about 55% (1.62–2.85 GHz) with three in-band attenuation poles while maintaining the normal radiation pattern. In particular, a low-profile property with the height of about 0.06 free-space wavelength is achieved.

A planar dual-band array with orthogonal circular polarizations (CPs) in the two frequency bands is proposed in this communication. The array is implemented on a single-layer substrate and easy to be extended to the design of a larger array. A new antenna element for such an array is exploited by symmetrically loading stubs on the edges of a square patch. In this communication, two pairs of orthogonal modes of the patch, namely, TM10/TM01 and TM30/TM03, are excited simultaneously and used to realize different senses of CP radiation in the two bands. An equivalent transmission-line model of this patch is then developed to describe its working principle and design procedure. To validate its effectiveness, a $2 \times 2$ -element array prototype operating at 2.53 and 3.59 GHz is designed and fabricated. Both the left- and right-hand CPs are obtained simultaneously in the dual bands, and the measured results are found to be in good agreement with the simulated ones. The measured radiation gains in the lower and higher bands are 10.8 and 12.5 dBic, respectively.

A single-layer microstrip-fed patch antenna with capabilities of both bandwidth enhancement and harmonic suppression is proposed. For this purpose, a pair of $\lambda $ /4 microstrip-line resonators is introduced and coupled in proximity to a rectangular patch. The wideband property can be obtained by making effective use of the two resonances introduced by the radiating patch and nonradiating $\lambda $ /4 resonators. Different from other reported dual-resonance patch antennas, the proposed antenna does not require the electrically thick substrate, so it has attractive low-profile property. Thanks to the good features of $\lambda $ /4 resonators and capacitive feeding scheme, harmonic radiating modes of the patch antenna can be significantly suppressed as highly demanded in modern highly integrated communication systems. The working principle, equivalent circuit, and design procedure are extensively described. Finally, a prototype antenna operating at 4.9 GHz is designed and fabricated. The measured results show that its bandwidth is 2.7 times wider than that of the traditional insert-fed patch counterpart, and the harmful spurious radiation from other higher order radiating modes has been effectively suppressed.

The design of fan-beam, compact-size, and high-gain horn antenna operating in E-band is presented in this paper. A zoned dielectric lens is integrated with the horn to correct the phase on its aperture. The lens is cut properly to reduce the weight. To show the effective of the design method, such an antenna covering 73–78 GHz is designed using CST-MWS simulation software. The simulation results show that voltage standing-wave ratio is under 1.6, and the antenna gain is above 35dB. It proved that the antenna has good focusing performance.

Swept blade technology was used to redesign the supercritical steam turbine sets that could improve the inner-efficiency of turbine sets and decrease the consumption of coal the noxious gas such as NOx. The eighth high-pressure stages, including static and rotor cascades, were selected as tested prototypes that were blew in the low-velocity wind tunnel. We used the five-hole ball head needle to measure the aerodynamic parameters distribution along the width and span direction of the high-pressure stage cascades. With the inkblot display technology, the limit flow spectrums were displaced in the blade surface and the endwalls. These tested data could be used to check the simulation results of CFD software. To improve the efficiency of the steam turbine high-pressure (HP) stage, we selected the supercritical steam turbine HP stage cascade blade as the prototype to research into its inner flow performance of the axial-swept blade by the CFD software. Two different redesigned blades, with ±20°, swept angle, and 30% swept height, named axial fore-swept and axial aft-swept, were built up. The stage passages flow field of the prototype blade, and the two redesigned swept blades were simulated using CFD software with stage interface planes between the stages. The CFD simulation results indicated that the leading edge of swept blades influenced the inlet flow field; the pressure in aft-swept blade stage in both endwalls was higher than in the middle and was beneficial to improve the passage flow properties of HP stage. But for the fore-swept HP stage, its pressure distribution was lower in both endwalls than in the middle and not beneficial to passage flow.

A dual-band and dual-circularly-polarized (CP) array antenna is presented to achieve the wide axial ratio (AR) bandwidths. The TM 10 and TM 01 modes of a dual-fed linearly polarized element are used to obtain the dual-frequency simultaneously. Sequential rotation technique with proper phase arrangement is used to achieve the dual-CP radiations. This antenna can radiate with left hand circular polarization (LHCP) in the lower band and right hand circular polarization (RHCP) in the higher band at the same time. Due to the single element on a single-layer substrate, the array antenna can be fabricated easily with less cost. This antenna has been investigated numerically and experimentally. Simulated results show that the −10-dB return loss bandwidths are 21.0% (8.6-10.6 GHz) and 12.5% (11.2-12.7 GHz) in the lower band centered at 9.5 GHz and higher band centered at 12 GHz, respectively. The 3-dB AR bandwidths in the low- and high-band are 8.4% (8.8-9.6 GHz) and 7.5% (11.8-12.7 GHz) respectively.

This paper presents a new approach to implement planar shared-aperture dual-band dual-circular polarization (CP) array antennas. The antennas can be fabricated on a single-layer substrate and extended to a larger array easily. In this approach, each array element is obtained by connecting two patches working at different frequencies directly. To form arrays with higher gain, two kinds of feed networks are described, which can be applied in systems where narrowband and wideband are needed, respectively. One is using the conventional feed network and the other is using the sequential rotation technique to further improve the CP axial ratio (AR) performance. Two prototype arrays with $4 \times 4$ elements are fabricated and tested in $X/Ku$ bands. Experimental results show that good CP characteristics are obtained, which agree well with the simulation results. For the first narrow-band prototype array, the 3-dB AR bandwidth is around 1.5% for both bands. For the second array using the sequential rotation technique, the bandwidth of return loss and AR are wider. In the lower band centered at 12.1 GHz, the ${-}10\hbox{-}\text{dB}$ return loss bandwidth is 8.3% and the 3-dB AR bandwidth is 14.2% [right-hand CP (RHCP)]; in the higher band centered at 17.4 GHz, the corresponding data are 18.9% and 14.9% [left-hand CP (LHCP)], respectively.

A novel substrate integrated waveguide (SIW) filtering crossover is presented based on the orthogonal degenerate TE201 and TE102 modes in SIW square cavities. By arranging the feeding ports and coupling windows at the cavity center, excellent transmission and isolation responses can be achieved successfully. In addition, the bandwidth of the crossover can be easily controlled using the well-established coupling matrix synthesis method, and the maximum bandwidth is determined by the acceptable isolation levels. A prototype operating at 20 GHz was designed and fabricated to verify this concept, and the measured results are in excellent agreement with the simulation results.

A miniaturized substrate integrated waveguide (SIW) filtering crossover is presented. The design concept is to fully exploit the orthogonal degenerate TE 201 and TE 102 modes in a SIW square cavity to realize the cross transmission, then four TE101-mode cavities are coupled to this square oversized cavity to implement the third-order response and more flexibly controlled bandwidth. Benefitting from the employment of the fundamental mode cavities, the footprint of the circuit has been reduced about 35% compared to our previous work. A prototype operating at 20 GHz is designed, fabricated, and measured for demonstration, showing excellent agreements between the simulated and measured results.

A wideband wide-coverage H-plane horn array with vertical polarization is proposed. Due to its light weight and low profile, the designed array is suitable for applications in spectrum monitoring systems on moving platforms. The switched-beam symmetrical array consists of four identical short H-plane horns. Pattern deterioration occurring in a high-frequency range is solved by inserting two pins in each horn. The measured impedance bandwidth is almost 100% for $\hbox{VSWR} owing to its fed structure with a thick-cylinder-loaded probe. The measured azimuth-plane beamwidth is about 90 $^{\circ}$ over the entire frequency range from 860 to 2500 MHz. Moreover, the measured results with the corresponding simulated results are presented and discussed in this paper.

Distributed compressive sensing (DCS) has been used in multiple-input multiple-output (MIMO) radar system. This application has led to substantial improvements over existing methods in MIMO radar. But there are also some challenges that should be resolved in order to benefit the most from DCS-based MIMO radar, such as radar signal with low signal to noise ratio and optimizing measurement matrix design. In distributed DCS-based MIMO radar context, this paper presents a cognitive mechanism for optimizing transmit and receive gain by applying the optimization guideline which based on the coherence of the sensing matrix (CSM) and signal-to-noise ratio. This paper proposed two kinds of method: the first one is to optimize transmit gain with the aim to maximize SNR, and the second one is to minimize CSM by adjusting receive gain. Simulations show that the proposed methods obtain significant better recovery performance than traditional DCS-based MIMO radar systems.

Graphene oxide (GO) was introduced into carbon fiber/epoxy composite using a wet process for impregnating carbon fiber by epoxy added with GO, which resulted in an enhancement in the interfacial performance and electromagnetic interference shielding effectiveness (SE) of composite. To investigate the reinforcing mechanism, we compared the reinforcing effect between graphene oxide and reduced graphene oxide through interlaminar shear strength test, microdrop test, scanning electron microscopy, and transmission electron microscopy. The results indicate that toughening effect plays the key role for the interfacial improvement of carbon fiber/graphene nanosheets/epoxy composite. By adding only 0.1 wt% GO, the composite achieved an 11% enhancement of interlaminar shear strength at the maximum of 117.45 MPa and a SE improvement about 10 dB in the range of 5–20 GHz in the meantime, giving rise to a highly practicable potential for industrial utilization. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

This article presents two novel resonators, that is, frequency selecting coupling structure loaded stepped-impedance resonator FSCSLSIR and π-section loaded FSCSLSIR. The resonator behaviors and guidelines are given to design FSCSLSIR dual-band bandpass filter BPF and π-section loaded FSCSLSIR triband BPF. The proposed dual- and triband BPF have very compact sizes of 0.13 λgd × 0.06 λgd and 0.115 λgt × 0.074 λgt, respectively. Moreover, good return loss, low insertion loss, and high band-to-band isolation can be observed, and the proposed FSCSLSIR dual-band BPF has an ultrawide stopband from 5.79 to 36 GHz. The experimental results are in good agreement with the simulations. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:427-435, 2015.

In this paper, a compact microstrip patch antenna with bandwidth enhancement and harmonic suppression has been presented. The radiating patch is coupled and excited by a microstrip stub which is a non-radiating quarter wavelength resonator. Because the coupling quarter wavelength resonator operates at another resonant frequency close to center frequency of the radiating patch, the bandwidth is enhanced effectively. The proposed antenna acquires 6.1% bandwidth (from 4.73 to 5.03GHz), with a satisfactory radiation performance within the bandwidth and the harmful higher order radiating modes have been obviously suppressed. Moreover, the single quarter wavelength resonator makes it more flexible to excite patch and easier to be arranged in arrays for its compact and simple structure.

In this paper, a simple method for reducing the cross polarization level of microstrip patch antenna is presented. The comb-like slots are utilized in the traditional microstrip patch antenna to improve the performance. With this method, the cross polarization level of patch antenna can be suppressed obviously, while the bandwidth will not be affected. The effectiveness of this method is verified by simulations.

In this paper, a multi-solution design of an arbitrary phase delay crossover is proposed. One of its characters is that the solution is not unique for a certain goal, which improving the flexibility of design procedure. The admittance matrix is utilized to obtain the design formulations for this novel structure. To validate the design method, two crossovers with 45°phase delay are designed and verified by theoretic verification and simulations.

A new correction method is proposed for the single RF channel digital beamforming (DBF) antenna array. In this array, each array element is followed by a $0/\pi$ phase shifter, and the element outputs can be recovered by the single channel through the time sequence phase weighting (TSPW) technique. The outputs can be used to form desired beams through DBF. The performance of the DBF is influenced by the imperfection of the phase shifters. To obtain the errors in each phase shifter, the online test method based on a single known plane wave is introduced. The online test results are used to correct the element outputs using the relationship between the actual and the incorrect outputs. Compared with another previously proposed correction method, the new method is simpler and more suitable for real time correction. The factors that may influence the capability of the correction are analyzed. To validate the proposed method, an eight-element prototype is measured, and the data are used to synthesize low sidelobe patterns. Results show that the sidelobe level and gain improvements after correction are 11.1 and 2.6 dB, respectively.

A wideband microstrip series-fed magnetic dipole array antenna is proposed. The five-element dipole array antenna is designed to achieve both wide bandwidth and high gain because of its microstrip series feeding structure. The low-profile low-cost array is suitable for applications such as wideband high-gain wireless communications. Measured and simulated results are in good agreement. The measured impedance bandwidth of the array is enhanced up to 28.6% (5.0–6.7 GHz). The radiation patterns show its advantages of high gain (about 10 dBi), endfire radiation and vertical polarisation.

For improve the driving safety and the technology development of inter-vehicle communication, the communication system of supply two vehicles based on GPS, wireless LAN and embedded technology was researched and designed. The system could send/receive driving data information between two vehicles, and display the necessary information on LCD for drivers. In the paper, the process of the system been researched and designed was described. Two applications based on the system were proposed. The system was not only to achieve the desired functionality, but also made foundation for later research. It had great practical value, and very important for technologies research of vehicle safety and intelligent transportation systems.

In this paper a specific construction method based on the NS-2 software environment was studied to simulate the inter-car communication and constitutes. And the implementation methods of inter-car communication were described. The simulation traffic environment what we have described have good use to the research of relate technologies in the intelligent transportation systems such as inter-car etc., and have a important meaning to the simulation experiment of inter-car and algorithm.

Perfect automotive air conditioner system can be improved to ensure pleasant air environment in a variety of external conditions, the driver can keep the brain cool, improve work efficiency, reduce fatigue and accidents, and thus guarantees driving safety. Because of the transient nature of automotive air conditioner and systematic non-linear, it is extremely difficult to establish the mathematical model for the system. Generally, to describe the transfer function or the state function of automobile air conditioner accurately is difficult, the control of the system can rarely obtain satisfying results. This article explored the procedures of introducing the digital PID control algorithm into the automotive air conditioner control system, and proposed an automobile air conditioner intelligent control system based on Increment-PID algorithm. Optimized control of automotive air conditioner system can improve its performance.