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KDM2A is a histone demethylase, which primarily catalyzes the demethylation of H3K36me2. Abnormal expression of KDM2A is observed in many types of cancers; however, the molecular events connected to KDM2A expression remain unclear. We report that KDM2A performs an oncogenic function in esophageal squamous cell carcinoma (ESCC) and is robustly expressed in ESCC cells. ShRNA-mediated knockdown of KDM2A resulted in a significant inhibition of the malignant phenotype of ESCC cell lines, whereas ectopic expression of KDM2A showed the opposite effect. We also analyzed the function of KDM2A using a CRISPR-CAS9 depletion system and subsequent rescue experiment, which also indicated a cancerous role of KDM2A. Interestingly, analysis of the gene expression network controlled by KDM2A using RNA-seq revealed an unexpected feature: KDM2A could induce expression of a set of well-documented oncogenic genes, including IL6 and LAT2, while simultaneously suppressing another set of oncogenes, including MAT2A and HMGCS1. Targeted inhibition of the upregulated oncogene in the KDM2A-depleted cells led to a synergistic suppressive effect on the malignant phenotype of ESCC cells. Our results revealed the dual role of KDM2A in ESCC cells, which may have therapeutic implications. • Ablation of KDM2A attenuates the malignant phenotype of ESCC cell lines. • Augmented expression of KDM2A promotes the malignant phenotype of ESCC cells. • KDM2A activates one set of oncogenic genes and represses another set of cancerous genes simultaneously. • Inhibition of activated oncogenes generates a synergistic antitumor effect in KDM2A-deficient ESCC cells. • The dual role of KDM2A may be used to develop a combination treatment for ESCC. [ABSTRACT FROM AUTHOR]

In this letter, a wideband two-dimensional (2-D) scanning multibeam array antenna is proposed using a novel beamforming network (BFN). First, a novel three-beam Butler matrix (BM) network, as the core of the BFN, is proposed and described. The BM network comprises a directional coupler, T-shaped power dividers, and coupling baluns, which avoids using crossovers and lossy lumped elements as in a conventional BM network. In addition, a dual-stripline structure is employed to combine multiple components, which considerably reduces the BM network aperture. Then, six three-beam BMs are stacked and interconnected to form a complete 2-D BFN, whose scanning features of two orthogonal planes are controlled by two sets of BMs. Finally, to verify the working principle of the BFN, a 3 × 3 all-metal antenna array is designed and combined with the BFN. Notably, the low-profile antenna element achieves a wide operating bandwidth of 34.5%. Furthermore, a prototype is fabricated and tested, which shows that the antenna realizes switched beams in nine directions, indicating that an excellent 2-D scanning function is realized. [ABSTRACT FROM AUTHOR]

The authors present a wideband circularly polarised antenna array consisting of a 10‐element ellipse dipole antenna and a feed network. A metal pillar is vertically loaded at the end of each ellipse dipole arm to extend the current path, thereby reducing the lateral dimension of the antenna element. For uniform coverage over the Earth's surface, antenna with an isoflux pattern is required due to its uniform power density over a wide coverage area. To obtain wideband and isoflux characteristics, the amplitude and phase distributions along the network are optimised by applying the hybrid of the genetic algorithm and particle swarm optimisation. Particularly, the feed network with broadband phase shifting performance is designed to attain a broad bandwidth requirement. The proposed antenna can achieve excellent impedance matching and axial ratio characteristics from 1.1 to 1.6 GHz. In addition, the isoflux radiation pattern is obtained with the beamwidth of ±21° where the gain is higher than 0 dBi in the elevation plane (xoz‐Plane). The realised gain is better than 10.2 dBi and the side lobes are below −14.2dB across the operating frequency. Finally, the antenna array is manufactured and measured, and good agreement is achieved between the simulation and measurement results. [ABSTRACT FROM AUTHOR]

A hat‐fed reflector antenna with large radius of ring‐shaped phase center (RSPC) is reported in this article. First, a new phase efficiency calculation model (PECM) based on new phase reference point is presented, which can accurately calculate the phase efficiency of a hat‐fed with arbitrary radius of RSPC. Second, based on the invented PECM, the hat‐fed can be optimized by using cosimulation method of HFSS and MATLAB, high aperture efficiencies are achieved in the whole band. To prove the validity of the new PECM, a hat‐fed reflector antenna with large radius of RSPC is designed, manufactured, and measured. The measured results are in good agreement with the simulations. The results show that the developed hat‐fed reflector antenna has achieved a VSWR of less than 1.18, the peak realized gain of 43.5 dBi and an aperture efficiency of higher than 67.4% in the entire band from 12.25 to 14.5 GHz. [ABSTRACT FROM AUTHOR]

A novel design concept to reduce the frequency ratio of a dual-band dual-circularly polarized (CP) microstrip patch antenna (MPA) is presented by using its reshaped TM10, TM01, and TM20 modes. First, the far-zone radiated fields of the traditional MPA are theoretically investigated. It demonstrates that the normal |Eθ| and |Eϕ| fields at xoz plane are orthogonally generated under its TM10 and TM01 modes, respectively. Unfortunately, its TM20 mode radiates the nonbroadside |Eθ| fields at xoz plane. Then, an open-ended stub is loaded around the edge of the radiator, aiming to reshape the TM20 mode as the broadside radiation. After that, the patch width is decreased with the loading of two shorting pins. The main target is to move the TM01 mode resonating between TM10 and TM20 modes. Finally, the proposed antenna is fabricated and tested. The results illustrate that its left-hand CP and right-hand CP radiation patterns are satisfactorily acquired at around 2.134 and 2.223 GHz, respectively, thus gaining a small frequency ratio of around 1.04. Meanwhile, the antenna holds the low-profile (0.02 free-space wavelength), small-backlobe, single-layer, single-fed, and single-radiator properties. [ABSTRACT FROM AUTHOR]

A novel design concept to reduce high H-plane cross-polarization of a shorted patch antenna (SPA) with broadside radiated patterns is presented by loading a pair of open-ended stubs. Initially, the nonbroadside $\vert E_{\mathrm {\theta }}\vert $ component of the traditional SPA at TM $_{\mathrm {1/2,2}}$ mode is demonstrated to be much larger than its broadside $\vert E_{\varphi }\vert $ component in H-plane or yoz plane radiation patterns. In order to maintain its peak radiation in the normal direction, the far-zone radiated fields of the antenna are theoretically studied and analyzed. The results demonstrate that the dual nodal lines of the TM $_{\mathrm {1/2,2}}$ modal fields could be gradually moved far away from each other by increasing the stub length. As such, its $\vert E_{\varphi }\vert $ and $\vert E_{\theta }\vert $ components in H-plane or yoz plane radiation patterns could be progressively strengthened and weakened, respectively. After that, by reallocating these dual nodal lines around the corners of the radiating patch, the nonbroadside radiated fields of TM1/2,2 mode are successfully transformed into the broadside radiation, while keeping a low H-plane cross-polarization level. Additionally, the symmetric open-ended stubs are folded so as to reduce the dimensions of the core radiator. In final, the proposed SPA is fabricated and measured. Simulated and measured results are found in good agreement with each other, and both of them illustrate that the antenna has satisfactorily acquired a normal radiation pattern at reshaped TM1/2,2 mode. Most importantly, its high H-plane cross-polarization is dramatically reduced from −4.3 to −21.4 dB as compared to the traditional SPA at TM1/2,0 mode. [ABSTRACT FROM AUTHOR]

In this paper, an offset reflector antenna with dual-beam and dual-polarization characteristics is developed to provide the angular diversity function for troposcatter communication system. The antenna system consists of a parabolic reflector and a dual-beam feed. For the dual-beam feed, two identical Ku-band feed elements are arranged side by side to generate two beams toward the reflector. The two beams are substantially nonoverlapping. The feed element is composed of a dielectric rod, a square waveguide, and an ortho-mode transducer. The dielectric rod is effective in reducing the beamwidth of the feed and providing more tapered illumination on the reflector in order to increase the antenna gain. Moreover, the developed antenna is able to produce two independent beams with the vertical and horizontal polarizations. The antenna was fabricated and tested with good agreement between the simulation and measurement results. The measured voltage standing wave ratios of the four feed ports are less than 1.5:1, and the beam separation angle is not more than 0.7° or about one time half-power beamwidth, and the antenna gain is higher than 45 dBi over the operating band from 14.5 to 15.35 GHz. [ABSTRACT FROM AUTHOR]

A novel broadband horizontally polarized (HP) omnidirectional antenna is proposed for meteor-burst communication system in VHF. The proposed antenna is composed of three bowtie dipoles, which are concentrically placed to form a loop antenna. The bowtie dipole is shorted at the terminal by folded elements in order to reduce antenna size. The bowtie dipoles are fed by a three-way power divider. A slotted line balun is employed to achieve broadband impedance matching and realize balanced-to-unbalanced transformation. The designed HP omnidirectional antenna exhibits a fractional bandwidth of 24.7% with VSWR < 2 ranging from 39 to 50 MHz. Uniform omnidirectional radiation patterns in the azimuth plane with HP have been obtained. The loop antenna provides a relatively low gain of no more than 1.5 dBi. Therefore, a two-element HP antenna array is developed to enhance its gain. In order to reduce longitudinal dimension of the array, the two loop antenna elements are placed in reverse and employ differential feeding method to realize in-phase current. Both the simulation and measured results are used to verify the design approach. [ABSTRACT FROM PUBLISHER]

Abstract: A planar Rotman lens antenna that generates multiple beams is presented over a wide angular range. The proposed multi‐beam antenna consists of a Rotman lens and a ten‐element printed Yagi antenna array. By properly comparing optical aberrations, expressing as the normalized path length errors Δl, the suitable ratio of on‐axis to off‐axis focal length (g = G/F) is acquired so as to minimize phase errors for the array elements. Ten dummy ports are employed to reduce the performance deterioration caused by energy reflection. A prototype with seven input ports was fabricated and measured, covering a wide scanning angle of 60° (–30°, 30°). The measured beam patterns show that the seven beam gains are distributed from 11.9 to 13.6 dBi under operating of 8.15 GHz. Both the simulated and measured results are used to verify the design approach. [ABSTRACT FROM AUTHOR]

A novel wideband circularly polarized (CP) antenna is presented in this article. The proposed antenna consists of a four-leaf clover patch, four L-probes, and wideband networks. Based on the tightly coupled mechanism, the four L-probes are formed as a ring with the adjacent ones kept close for strong mutual coupling. Consequently, the proposed antenna realizes a wideband impedance matching. Meanwhile, the four-leaf clover patch is put closely inside of the ring for further improving the impedance bandwidth, which is proximity-coupled fed by the four sequential-rotation L-probes with phase of 0°, 90°, 180°, and 270°. The four L-probes are connected to the respective ports of a wideband feeding network by a two-stage impedance transforming network. The measured results indicate that the proposed design has an impedance bandwidth of 66.7% from 1.0 to 2.0 GHz for VSWR ≤ 2 and a 3-dB axial ratio bandwidth of 56.5% from 1.08 to 1.93 GHz. Furthermore, in the operating bandwidth, stable and symmetry radiation patterns and high gain are obtained. The design has a 3-dB gain bandwidth of 38% from 1.3 to 1.9 GHz with a peak gain of 8.5 dBic. [ABSTRACT FROM AUTHOR]

The paper proposes a wideband bowtie antenna for indoor base station applications. By using the inverted L-shaped coupling feed structure, the impedance bandwidth of the lower band is improved; while using the four tuning stubs, the upper band is enhanced. Thus, a wide impedance bandwidth of about 77.8% (VSWR les; 2) ranging from 1.38 to 3.14 GHz is obtained. In addition, by connecting two folded elements to the patches of the bowtie dipole, the compact dimensions of the antenna can be achieved. It also provides stable peak gain, unidirectional radiation patterns and low cross-polarization over the whole operating band. Owing to these good performances, the proposed antenna is very suitable for the recent indoor base station wireless communication services such as 3G, WiFi, WiMax, Bluetooth and LTE applications, etc. [ABSTRACT FROM AUTHOR]

A new design of a circularly polarised antenna based on the tightly coupled mechanism is presented. The proposed antenna consists of four tightly coupled dipoles, four impedance transforming networks and a wideband feeding network. Owing to the strong mutual coupling between coupled dipole elements, the proposed antenna realises a wide operating bandwidth. A prototype is manufactured and measured to validate the method. The measured results indicate that the proposed design provides a 10 dB return loss bandwidth of 101% (1.7–5.2 GHz) and a 3 dB axial ratio bandwidth of 77% (2.0–4.5 GHz). The design has a 3 dB gain bandwidth of 56% from 2.6 to 4.6 GHz with a peak gain of 10.4 dBic. Acceptable agreements can be obtained between the simulated and measured results. [ABSTRACT FROM AUTHOR]

ABSTRACT A wideband circularly polarized (CP) antenna with high gain is proposed. The circular polarization performance is obtained by two pairs of orthogonal bowtie dipoles with a coaxial balun feed and a broadband 90° hybrid feed network. Particularly, a design of rectangular ring with eight shorted posts is added around the bowtie dipoles, which can obtain a high gain. To further improve the gain of the novel antenna, a circular ring is placed around the rectangular ring on the same plane. With such an arrangement, the proposed antenna delivers a higher gain than that of the conventional dual-fed type CP antenna. The measured results show that the proposed antenna can achieve a measured impedance bandwidth for VSWR ≤ 1.5 of 61.5% and a 3-dB axial ratio bandwidth of 66.7%. The antenna has a stable peak CP gain better than 10.3 dBi ranging from 1.1 to 1.6 GHz. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1274-1277, 2014 [ABSTRACT FROM AUTHOR]

ABSTRACT The wideband performance of a bowtie antenna with Γ-shaped strip feed and tuning stubs is presented. Besides two folded elements connecting the patches of the bowtie dipole for a compact dimension, the Γ-shaped strip feed structure and the four tuning stubs to effectively improve the impendence matching can be used for bandwidth enhancement. A wideband impedance characteristics of about 58.6% for VSWR ≤ 1.5 ranging from 1.58-2.89 GHz is obtained and the stable peak gain of around 9 dBi, unidirectional radiation patterns and low cross-polarization over the whole operating band are also achieved. It is very suitable for the recent wireless communication services for the indoor-base station such as 3G, WiFi, WiMax, Bluetooth, and LTE/2.5 applications, and so on. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2145-2149, 2013 [ABSTRACT FROM AUTHOR]

A novel miniaturized dual-band monopole antenna loaded with two types of loops is presented. The split loop is loaded at the center of the monopole for dual-band operation and the rectangular loop loaded at the top is for miniaturization. The novel miniaturization technique is used as a self resonant topology. The monopole below its resonant frequency is known to possess a capacitive reactance and the loop below its resonant frequency has an inductive reactance. So an inductive loop is used to match a below-resonant monopole for miniaturization. As an example of this principle, a miniaturized dual-band antenna prototype for WLAN applications is designed, fabricated, and tested. Measured results show that the antenna offers higher gains and better efficiencies than the unloaded monopole. The radiation patterns are seen to be unaffected by the presence of the top loaded loop. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1236-1239, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26784 [ABSTRACT FROM AUTHOR]

A wideband circularly polarized antenna with Γ-shaped feed is presented.The proposed antenna is formed by two shorted bowtie patch antennas and two L-shaped electric dipoles. It can achieve a measured impedance bandwidth for voltage standing wave ratio (VSWR) ≤ 1.5 of 52% and a 3-dB axial ratio bandwidth of 55%. For the entire half-power beamwidth, the axial ratio can be kept below 3 dB. A prototype has been fabricated and tested, and the experimental results validate the design procedure. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:153-156, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26503 [ABSTRACT FROM AUTHOR]

A dual-resonant patch antenna applicable to active radio frequency identification (RFID) tags is designed. The designed antenna has been skillfully integrated with the active RFID tag circuit. The antenna consists of two parts. One part comprises stacked shorted patches and a ground plane. The other part is an active tag circuit mounted on the bottom of the antenna. The measurement results reveal that the antenna has the return loss less than -10 dB within the bandwidth of 42 MHz (from 911 to 953 MHz), which totally covers the 5 MHz bandwidth from 920 to 925 MHz (The band is also allowed for passive RFID) requirement for active RFID in China. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1280-1284, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26000 [ABSTRACT FROM AUTHOR]

Tm3+ doped β-rhenanite (β-NaCaPO4) series were synthesized by solid-state reaction. The crystalline structure of β-rhenanite was simulated and the photoluminescence properties of NaCa1-x PO4:xTm3+ (0