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Recent researches have proved that circular RNAs (circRNAs) act as an important role in many diseases. Our study aims to uncover the role of circ-ABCB10 in the progression of non-small cell lung cancer (NSCLC).Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was utilized to detect circ-ABCB10 expression in NSCLC patients. Then, we conducted Cell Counting Kit-8 (CCK-8) assay, colony formation assay, Ethynyl deoxyuridine (EdU) incorporation assay, cell cycle assay, and cell apoptosis assay in treated NSCLC cells. Besides, further experiments including RT-qPCR and Western blot assay were performed to explore the potential mechanism in vitro.Circ-ABCB10 expression level was significantly higher in NSCLC samples comparing to that in adjacent tissues. Moreover, functional assays showed that the cell growth ability of NSCLC cells was inhibited after circ-ABCB10 was knocked down. In addition, the cell apoptosis of NSCLC cells was promoted after circ-ABCB10 was knocked down. Also the expression of KISS1 was upregulated by the knockdown of circ-ABCB10. Furthermore, it was found that KISS1 expression was negatively correlated to the circ-ABCB10 expression in NSCLC tissues.Results above indicated that circ-ABCB10 promoted cell proliferation and inhibited cell apoptosis of NSCLC by suppressing KISS1, which suggested that circ-ABCB10 may be a potential therapeutic target in NSCLC.

Previous studies have shown that long non-coding RNA (lncRNA) HOXA-AS2 is a cancer-promoting gene. However, the role of HOXA-AS2 in non-small cell lung cancer (NSCLC) has not been reported. This study aims to investigate the expression characteristics of HOXA-AS2 in NSCLC and whether HOXA-AS2 can promote the malignant progression of NSCLC by regulating microRNA-216a-5p.Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to examine the HOXA-AS2 level in 40 pairs of NSCLC tumor tissue samples and adjacent ones. Then, the relationship between HOXA-AS2 expression and clinical indicators and prognosis of NSCLC was analyzed. Meanwhile, qRT-PCR further verified the expression level of HOXA-AS2 in NSCLC cell lines. Also, HOXA-AS2 knockdown and overexpression models were constructed using lentivirus in NSCLC cell lines, and the effects of HOXA-AS2 on the biological function of NSCLC cells were analyzed using the Cell Counting Kit-8 (CCK-8), transwell migration, and cell wound healing assays. Finally, Western blotting assay and cell recovery experiment were used to explore the regulatory mechanism of HOXA-AS2 and microRNA-216a-5p in NSCLC.In this experiment, qRT-PCR results revealed that HOXA-AS2 level in NSCLC tumor tissue specimens was remarkably higher than that in adjacent tissues. Compared with those with low expression of HOXA-AS2, the patients with high expression had a higher incidence of distant metastases and a lower overall survival rate. The proliferative and metastasis abilities of the cells in the HOXA-AS2 overexpression group were remarkably increased when compared with the control group, while the opposite results were observed in HOXA-AS2 silence group. Subsequently, qRT-PCR verified that microRNA-216a-5p level was remarkably decreased in NSCLC tissues and negatively correlated with HOXA-AS2 expression. In addition, the result of the cell recovery experiment and Western blotting revealed that there might be a mutual regulation between HOXA-AS2 and microRNA-216a-5p, the two of which could jointly regulate the malignant progression of NSCLC.The results indicate that lncRNA HOXA-AS2 is upregulated in NSCLC and is remarkably associated with distant metastasis and poor prognosis of NSCLC patients. In addition, lncRNA HOXA-AS2 is found to be able to promote the malignant progression of NSCLC via regulating microRNA-216a-5p.

A binary programmable metasurface is designed to generate arbitrary images in the near-field region. By adequately changing the coding sequences of the metasurface, these images can be detected by a single fixed probe, hence realizing direct transmission of near-field images.

We propose a class of illusion devices that can be realized using gradient index materials. The devices are designed using quasi-conformal-mapping transformation optics through a two-step transformation, with the first mapping from the virtual space to the intermediate space and the second from the intermediate space to the physical space. These devices can render the object invisible, magnify/minify its scattering, reshape its scattering pattern, or move the object virtually. All devices are inherently broadband, low loss, and easily realizable. Moreover, the devices can be scaled down to work at optical frequencies. Numerical simulations confirm the performance. Three-dimensional illusion devices with the rotational symmetry can also be designed and implemented using the method.

We have designed a two-dimensional planar lens based on the complementary I-shape units. The resonant frequencies for these units are extremely high so that at low frequencies the effective permittivity and permeability change slowly, which is especially useful for constructing broadband and low-loss electromagnetic devices. The distributions of refraction index for the planar lens have been evaluated, and numerical simulations have been made to determine the geometry dimensions of the corresponding units. The fabricated sample has been tested in a two dimensional near-field microwave scanning apparatus. Distributions of the measured electric fields show that the lens has good focusing ability at the working frequencies and also exhibits broadband and low-loss properties under the excitation of plane waves.

We have investigated the electromagnetic properties of arbitrarily-shaped three-dimensional concentrators based on the field-transformation theory for the first time. Up to now, many researchers are inclined to investigate the characteristics of the two dimensional optical-transformation devices instead of the three-dimensional (3D) ones due to the huge simulation burden for the commercial electromagnetic softwares. The field transformation theory has provided us a smart and powerful way to study such 3D problems. Analytical expressions for the fields and power flows inside the concentrators have been presented accurately, which have never been considered before. As examples, the spherical and cubic concentrators are discussed in more details. The study shows that the magnification of fields and power-flow densities inside the central parts of concentrators is only dependent upon the spatial compression ratio in the transformation equations, which gives a theoretical proof to the numerical simulations.

Electric resonant structures are primary unit cells to construct single negative permittivity metamaterials, which are also widely used in the design of novel microwave components. In this paper, the relative equivalent circuit model is first studied, the resonant characteristics of such structure is analyzed, the factors effected on the distribution of zero and pole transmission points are presented, based on which a realizable way to design filters with narrow transition-band from stop-band to pass-band is elicited. Then, a frequency selective surface (FSS) is designed with –3.9 dB attenuation in 40 GHz near the working frequency of 0.7 THz. The S parameters are also compared with those of a conventional electric resonant structure, from which we observe that the later has larger size besides wider transition bandwidth. On the other hand, the novel FSS can increase the utilization factor of frequency spectrum. In order to further decrease the transition bandwidth, three layers of the FSS structures are ...

We propose a simple transformation method of two different kinds of electromagnetic waves using metamaterials. We design the electromagnetic parameters with spatial variations to control the phase speeds of waves in different directions. Then we investigate the transformation from cylindrical and spherical waves to plane waves. Full-wave numerical simulations validate the proposed method. Comparing with the optical-transformation approach, the proposed structures are much easier to be realized, which can be used either as high-performance antennas or focusing lenses.

We present electromagnetic invisible cloaks and concentrators which are composed of inhomogeneous and anisotropic metamaterials with a square-shaped outer boundary and a circular-shaped inner boundary. Using the technique of coordinate transformation, closed-form formulations of the permittivity and permeability tensors have been derived for the metamaterials to realize the invisible cloaking and to concentrate electromagnetic waves. Full-wave simulation results are given to validate the non-rotationally invariant cloaks and concentrators.

We propose a novel structure to achieve the high power generation and transmission in a parallel-plate waveguide by transverse magnetic (TM) wave coupling through an aperture on one boundary of it. As we know, the energy emitted by the source outside the waveguide is coupled into the waveguide through a small aperture and can be transmitted if some electromagnetic (EM) conditions are satisfied. But the transmit power is at the same level of and could not exceed the source power in such a conventional waveguide filled with right-handed material (RHM). However, if a left-handed material (LHM) slab is inserted between the source and the aperture, the transmit power in the waveguide can be extremely enhanced. Furthermore, if the waveguide is filled with two layered unequal-thickness RHM and LHM slabs, the transmit power in each layer becomes even larger. The method of moments is implemented to give the exact analysis and we can clearly observe such important phenomena from the numerical results.

A rigorous and efficient algorithm which combines the fast multipole method and conjugate gradient fast Fourier transform is presented for the full-wave analysis of large-scale finite-sized periodi...

The interactions of a slightly lossy left-handed medium (LHM) slab with three-dimensional (3D) horizontal electric dipoles (HEDs)are studied. Different from other types of sources, HED will excite both transverse electric (TE) and transverse magnetic (TM) modes inside the LHM slab. We have investigated the imaging and localization properties of the LHM slab excited by a single HED or two opposite HEDs. We demonstrate that nearly all propagating components and parts of evanescent components emitted by a single HED can be recovered at the image points to achieve the super-resolution. We also show that nearly all electromagnetic energies produced by two opposite HEDs located at image points of the LHM slab are localized in a region between the two sources. Numerical results validate our conclusions.

We describe a new physical picture inside a parallel-plate waveguide excited by a line current source. Generally, the electromagnetic (EM) fields inside the waveguide are represented in closed forms of Sommerfeld-like integrals. When the waveguide is filled with air or lossless layered media, we show that EM fields are contributed by both continuous spectra and poles, which correspond to 'continuous modes' and guided modes inside the waveguide. Due to the pairing appearance of poles, the guided modes are composed of physical and unphysical components. We have further shown that the continuous modes contain propagating and evanescent waves, where the former eliminates exactly the unphysical guided modes and the later contributes the near-field effect of the source. Hence the existence of continuous modes makes the wave propagation inside the waveguide physical. When the guidance condition is not satisfied, only evanescent waves are included in continuous modes, which represents the storage of energies near...

Compact resonator filter and power divider are investigated and designed using a simplified meta-structure where the series capacitor in the conventional composite right/left-handed transmission-line (CRLH) structure is not required. The design is based on the resonant frequency of shunt microstrip inductor and capacitor connected to ground. The filter and power divider are fabricated and measurement results show good agreements with full-wave simulation results. The resonant frequency and bandwidth of the filter can be easily optimized from the physical sizes of unit cell. Different power levels at two output ports in the power divider are achieved by changing the length of coupling lines with negligible phase difference. Since the series capacitors are not required in the design, the proposed filters and power dividers have quite compact sizes.

The performance of distributed arrays and distributed isotropic receivers in EM source localizations are numerically studied in this paper. The Possible Localization Regions (PLR) of the source in the free space obtained using these two kinds of receivers are analytically studied first. The source PLR obtained using distributed arrays in free space is demonstrated to be smaller than that obtained using distributed isotropic receivers. At the end of this paper, a numerical source localization result in complex urban environment obtained by ray tracing technique confirms this argument. Introduction With the development of wireless communication, the electromagnetic (EM) source localization becomes a hot topic in seeking the EM pollution sources, enhancing the communication performances, and so on. Many localization techniques have been proposed in the literature, e.g., blind signal separation (BSS) using independence component analysis technique (ICA) [1], and ray tracing method [2]-[4], and so forth. In this paper, we only concern on the ray tracing method. In the ray tracing method, the fields on the receivers generated by the source are measured first. Subsequently, the interesting region in which the source is located is divided into some discrete grid points. Each of these grid points maybe the approximation of the true source, which depends on whether it satisfies the judgment of a criterion, viz., cost function. The definitions of the cost functions can be diverse. It can be defined as the average square root of the relative differences between the fields on the receivers generated by the true source and that by the guessed source. I also can be defined as the 2-norm between the normalized field vectors generated by the guessed source and that by the true source. (The elements in the field vectors are the fields on the receivers.) In this paper, if the power of the source is known, we use the former one. Otherwise, we use the later definition. No matter what definitions of the cost function we use, there always exists a problem, viz., the numerical methods exist the modeling errors, which will cause the uncertainty of localization. This suggests that we can’t localize the true source points but just delimit a region that contains this source points. Assume that the upper bound of the modeling error is e0. Thus we can only get a region whose points ~r ′satisfy the inequality‖u(~r, ~r′)− u∗(~r, ~r′ 0)‖ ≤ e0, where u(r, r′) and u ∗ (~r, ~ r′) denote the simulated field and the measured field, respectively, while ~r0 is the true source point. (Note, u(r, r ′)and u ∗ (~r, ~ r′)can have different definitions as discussed in the next sections.) We call this region the Possible Localization Region (PLR). In the next section, we will analytically study the free space PLRs obtained by using distributed isotropic receivers and arrays, respectively. By the way, we would like to mention that because the measured data generated by the true source can’t be easily obtained, thus we just use the simulated data, and then, the points in the PLR should satisfy ‖u(~r, ~r′)− u(~r, ~r′ 0)‖ ≤2e0. (For saving space, its derivation will not be presented here.) Analytically Studying the PLR for Socalization in Free Space Because it is difficult to analytically study the source localization in complex urban environment, we only analytically study the PLR for free space localization problem. At first, let us study the PLR obtained using the distributed isotropic receivers. The field at point ~rgenerated by the source at point ~r′ in the free space can be expressed as u(~r, ~ r′) = E0/ ∣∣~r − ~ r′ ∣∣ c (1) Progress In Electromagnetics Research Symposium 2005, Hangzhou, China, August 22-26 741 where the superscript c denotes the range index and c=0.5 (for 2D case) or 1 (for 3D case). Assume the true source and the n receivers are located at the original point ~ O = (0, 0) and the points ~ri, respectively, where i = 1, · · · , n. At receiver ~ri, the relative difference between the field generated by the source at any point ~ r′and the original point is written as ∆u(~ri, ~r ′) = (u(~ri, ~r ′)− u(~ri, ~ O))/u(~ri, ~ O) (2) We define the cost function as Cost Function = ‖∆ū(~r′)‖ , (3) where ∆ū(~r′) = [∆u(~r1, ~ r′), · · · ,∆u(~rn, ~ r′)]T . From the discussion in the introduction, we know that the PLR in the interested region is defined as a region whose space points ~ r′ satisfy the inequality Cost Function = ‖∆ū(~r′)‖ ≤ 2e0 (4) Substituting (1) and (2) into (4) we obtain ||∆u|| = √√√√ n ∑ i=1 [[1 + (|~ r′|/|~ri|)2 − 2|~ r|/|~ri | cos(θ′ − θi)]− c 2 − 1] ≤ 2e0 (5) where θ′ and θi are the polar angles of points ~ r′ and ~ri. To directly solve (5) is difficult. Fortunately, when n ≥ 2, the PLR becomes some small areas in the interesting region. It means that the inequality |~r′|/|~ri| << 1 must holds in one small area of the PLR that contains the true source point. Hence, applying the Taylor approximation in (5) and neglecting the higher order terms of |~r′|/|~ri|, we simplify (5) as, |~r′|2 ≤ 4e 2 0 c2 n ∑ i=1 cos2(θ′−θi) |~ri|2 (6) Hence the area of PLR is analytically expressed as

For weak scatterers, simple relations have been discovered between physical properties and the Fourier transforms of their scattering fields, but they are invalid under strong-scattering conditions. In this paper, a microwave networking technique is used to investigate the one-dimensional inverse scattering problem, from which a novel inverse scattering solution for the permittivity profile is derived by considering the equivalent microwave network of the permittivity profile discontinuity at the interface of free space with the medium. This novel solution is essentially different from previous relations and is valid for both weak-scattering and strong-scattering conditions. Closed-form and numerical reconstruction examples show that the novel solution is accurate in comparison with exact theory and is applicable to both continuous and discontinuous permittivity profiles.

The multilayered medium modelled by the Cantor bar is a kind of self-similar structure, which has found wide applications in some optical and quantum areas. In this paper, reflection and transmission properties of arbitrary fractal Cantor bar layers are investigated first by using a self-similar networking method. Furthermore, the inverse scattering approach for this fractal structure is then researched, in which the fractal dimension, the dielectric characteristics, and the self-similar structure of the fractal system are reconstructed from the reflection spectrum illuminated by a normally incident plane-polarized electromagnetic wave. Some reconstruction examples are given to show the validity of this method.

With the developement of metamaterials in recent years, more and more interests have been attracted in the potential applications of these novel materials. Metamaterials are usually composed of periodic subwavelength units, which can produce electric or magnetic responses under the excitation of external incident waves. Since the characteristic dimensions of the composing units are far smaller than the working wavelength, effective medium theory can be utilized to describe the electromagnetic properties of the periodic structures. A number of applications have been verified by experiments like invisible cloaks, microwave lens and tunneling structures [1–3].

The UTD analysis to the diffraction of electromagnetic (EM) waves by smoothly convex surfaces is of great importance in many problems, such as the EM compatibility, the analysis of coupling between two antennas, and the estimation of scattering properties. When a ray illuminates on the curved surface at grazing incidence, the ray-propagating direction is tangent to the curved surface at the incident point, and then surface rays are launched. These surface rays, or creeping waves, propagate along geodesic paths on the convex surface starting from the incident point. Hence the ray tracing of creeping waves on the convex surface is a key process in the UTD method. Usually, some typically geometric objects are used to approximate a certain of objects for engineering applications. However, it is difficult to use such typically geometric objects to approximate arbitrarily-shaped objects, which limits the application of the UTD method.

A novel microstrip phase shifter is presented using metamaterial structures. The phase shifter is composed of complementary split-ring resonators (CSRR) and complementary electric-LC (CELC) resonators to realize the 180 degrees of phase difference. The added insertion loss is only 1.33 dB at 16.8 GHz in a transmission line, which is originally 64.5 degrees long. Moreover, a new design method to control the phase difference by changing the effective permittivity and permeability is proposed.

This article presents the design of an inexpensive, efficient, and electrically small antenna based on metamaterial- inspired structure fed by the coplanar waveguide (CPW). The size of the proposed antenna is 12 mm x 12 mm with the resonant frequency of 1.47 GHz. Details of the proposed antenna are presented, with full-wave simulation results to support the design.

This paper concerns the simulation of inverse synthetic aperture radar (ISAR) image for radar targets based on the shooting and bouncing ray (SBR) method. Contrary to the conventional approach where the ISAR image is obtained by inverse Fourier transforming to the scattering field, we adopt a newly-developed method [8], where the Fourier transformation has been merged into the SBR algorithm. Such a method has been improved and used in the imaging of real-size aircraft. High resolution two-dimensional ISAR images have been obtained. Hence such a method is considered as a general tool for the characterization of large and complex targets.

A novel matrix perturbation theory to the eigenequation [h][u] = Δ[u] is investigated, in which the perturbation solutions to eigenvalue Δ and eigenvector [u] are given. One of the applications of the above theory-application in a microwave resonate cavity-is researched. © 1993 John Wiley & Sons, Inc.

The time-domain characteristics of terahertz radiations emitted from a biased large-aperture photoconductive antenna trigged by an ultra-short optical pulse are studied. Succinct explicit expressions in the surface field and in the far field for the emitted THz radiation fields are deduced based on the well-known current-surge model. The expressions indicate that the THz radiations in the surface and far fields are mainly affected by the incident light intensity, the incident light wavelength, the carrier relaxation time, the reflectivity illuminated at the photoconductor, the carrier lifetime, and the incident light pulse width. The characteristics of THz radiation in the surface and far fields are discussed, and the phenomena of changes in the radiation peak values, the radiation pulse width, and the rising edges are explained in details. Especially the changes in surface fields are explained with the increasing of the ratio of luminous flux. The numerical results indicate that the emitted THz radiation intensity can be increased by enhancing the ratio of luminous flux, prolonging the carrier lifetime, or reducing the incident light pulse width. To avoid the shielding effect of the radiation field, an effectively method is presented that the intense of the incident laser pulse could be divided into multiple beams with low energy to trigger the photoconductive antenna, thus the THz radiation power can be further increased significantly.

Analysing the relations between TCM syndrome differentiation type and pathology in 312 patients with gastric cancer, the authors put forward the syndrome differentiation type of deficiency of vitality and excess in superficiality. The studies showed that the four syndrome types of deficiency of vitality such as Spleen-Stomach deficiency, Qi-Xue deficiency, Yin deficiency and inner heat, Spleen-Kidney Yang deficiency and the three syndrome types of excess in superficiality such as Liver-Stomach disorder, blood stasis and stagnation of Qi, Phlegm-dampness and stagnation of toxic. The same changes in pathologic characteristic of both were from early to late stage, the infiltration getting deeper, the tumor getting larger and the metastasis of lymph nodes around the stomach from little to much. Their difference was that in the deficiency of vitality syndrome-type, the chief manifestation was in nest or spread infiltration type which became serious by degrees, whereas in excess in superficiality type, the reaction of lymphoidocytes around the cancer was decreasing. The studies also showed that in most syndrome types of Spleen-Kidney Yang deficiency and Phlegm-dampness and stagnation of toxic, the tumor occurred in wide-range and the degree of tissue differentiation was quite low. The authors suggested that there might be morphopathologic basis in TCM syndrome differentiation types and the conclusion has practical value in guiding clinics.

A simple scheme of a profile inversion from the reflection data is obtained for a half-space weakly lossy medium. We have developed two approximations for reconstructing the permittivity and the conductivity profiles, both of which have closed forms.