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Bandstop filters (BSFs) have many applications in suppressing interference signals and shielding specific bands. Among them, reconfigurable BSFs that cover more frequency bands by switching modes have great research value. In this paper, a novel synthesis approach for compact reconfigurable BSFs with controllable equal-ripple performance is proposed. By switching the ON/OFF state of the positive intrinsic negative (PIN) diode, the proposed reconfigurable BSF can be switched between single-BSF (S-BSF) and dual-BSF (D-BSF). Based on the synthesis approach, the equal-ripple levels of stopband and passband for S-BSF and D-BSF can be independently controlled. To verify, the equal-ripple levels of stopband and passband for S-BSF state and D-BSF state are independently controlled in four groups of examples. Finally, a reconfigurable BSF with a miniaturized size is designed and fabricated. The fabricated reconfigurable BSF behaves with 15 dB and 10 dB return loss (RL) in two different passbands of the D-BSF state, and 25 dB bandpass RL and controllable stopband rejection (SR) for the S-BSF state. The measured results are in good agreement with the electromagnetic (EM) simulation results.

In this paper, a parallel transmission-line transformer with complex terminal loads is introduced for dual-frequency design. Through analyzing the different cases of complex terminal loads conditions, there are four different mapping patterns of designable regions on the Electrical Length-Electrical Length (EL-EL) plane. By adding an extra vertical Frequency Ratio (FR) axis, a novel 3D cube can be created on the FR-EL-EL coordinate system, then the designable ranges of frequency ratio can be easily drawn in this 3D cube. Therefore, the visible 3D mapping approach is newly reported for matching the complex terminal load of parallel transmission-line transformer at two different frequencies. For the certain pattern, a clearly boundary could be drawn to distinguish the designable and undesignable ranges. For verification, two examples are designed, fabricated and measured. Simulated and measured results are matched very well.

In this paper, a novel synthetization approach is proposed for filter-integrated wideband impedance transformers (ITs). The original topology consists of N cascaded coupled line sections (CLSs) with 2N characteristic impedance parameters. By analyzing these characteristic impedances, a Chebyshev response can be derived to consume N + 2 design conditions. To optimize the left N − 2 variable parameters, CLSs were newly substituted by transmission lines (TLs) to consume the remaining variable parameters and simplify the circuit topology. Therefore, there are totally 2N − N − 2 substituting possibilities. To verify the proposed approach, 25 cases are listed under the condition of N = 5, and 7 selected cases are compared and discussed in detail. Finally, a 75–50 Ω IT with 100% fractional bandwidth and 20 dB bandpass return loss (RL) is designed and fabricated. The measured results meet the circuit simulation and the EM simulation accurately.

In this study, a novel polarization converter (PC) based on square lattice photonic crystal fiber (PCF) is proposed and analyzed. For each square unit in the cladding, two identical circular air holes are arranged symmetrically along the y = x axis. With the simple configuration structure, numerical simulations using the FDTD analysis demonstrate that the PC has a strong polarization conversion efficiency (PCE) of 99.4% with a device length of 53 μ m, and the extinction ratio is −21.8 dB. Considering the current PCF fabrication technology, the structural tolerances of circular hole size and hole position have been discussed in detail. Moreover, it is expected that over the 1.2∼1.7 μ m wavelength range, the PCE can be designed to be better than 99% and the corresponding extinction ratio is better than - 20 dB .

Malignant cells show increased glucose uptake in vitro and in vivo. High expression of the glucose transporter-1 gene (GLUT1) has been found in many human tumor tissues. The aim of this study was to investigate the correlation between GLUT1 expression in breast carcinomas of Taiwanese patients and clinical prognostic parameters. Twenty-eight (71.8%) of the 39 breast carcinomas analyzed showed positive GLUT1 expression with different intensities: 1+, 19 cases (48.7%); 2+, 6 cases (15.4%), 3+, 3 cases (7.7%). No significant correlation was seen between GLUT1 expression and clinical prognostic parameters such as tumor size (p = 0.085), age (p = 0.4528), axillary lymph node metastasis (p = 0.9562), nuclear grade (p = 0.6895), estrogen receptor-positive (p = 1.0000), and progesterone receptor-positive (p = 0.9689).