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In this paper, some new types of artificial transmission lines, compatible with monolithic-microwave integrated-circuit/miniature hybrid-microwave integrated-circuit technology are presented. In the new designs, short subsections of different lines are connected together to achieve the needed performance of various transmission-line functions such as impedance transformation, power coupling, etc. Theoretical calculations are given and some typical design data are provided, including models of extremely low impedance lines, which are very practical in the design of microwave power amplifiers and oscillators using heterojunction bipolar transistors or high electron-mobility transistors. Calculation results are validated by simulations and experiments. The proposed structures are very flexible and can easily provide transmission lines with widely varying characteristics. Index Terms - Coplanar waveguides, microstrip, microwave integrated circuits, MMIC's, transmission lines.

In this paper, a new structure of tightly coupled lines compatible with monolithic-microwave integrated-circuit/minature hybrid-microwave integrated-circuit (MMIC/MHMIC) technology is introduced. Different from previous designs, short subsections of two or more different coupled lines are alternatively connected together to achieve the needed performance of a single-section coupler or phase shifter. Theoretical calculations are given and some typical design data are provided. A design example of a wide-band coplanar-waveguide (CPW) quadrature coupler using standard MMIC foundry technology is provided. Only metal-insulator-metal (MIM) capacitors and air-bridges are used to achieve tight coupling - no via holes are necessary. Experimental results are in good agreement with simulations. The proposed structure of coupled lines is very flexible and easily achieves very tight coupling factors. Index Terms - Coplanar waveguides, coupled transmission lines, couplers, microwave integrated circuits, MMIC's.

Lowering cost will prompt the sustainable development of sugarcane‐based ethanol industry. In this work, we developed a low‐cost process for ethanol production from sugarcane by a genetically engineered Zymomonas mobilis. Fermentation media were first optimized, resulting in a 15.54% increase in ethanol fermentation efficiency as compared to control media. To further reduce the byproduct levan formation, a levansucrase‐encoding gene of Z. mobilis, sacB, was deleted through the type I‐F CRISPR‐Cas system, which resulted in a further elevation of both ethanol conversion ratio and productivity comparing with the starting strain ZMS912 (87.50% vs. 76.77%, 1.95 g/L/h vs. 1.71 g/L/h). Moreover, we conducted fed‐batch fermentation for ethanol production using sugarcane juice in 5 L bioreactors and employing the optimized media and engineered strain. The results showed that maximum ethanol titer of 81.59 g/L and productivity of 5.83 g/L/h were achieved. Finally, preliminary techno‐economic assessment demonstrated that our efforts to modify media and strain could reduce the processing cost of ethanol production from sugarcane juice, which provides the feasibility for economic ethanol production in the future. [ABSTRACT FROM AUTHOR]

A simple recursive algorithm is presented based on the method of lines for the analysis of multilayered multiple microstrip lines or slots. Our previously proposed scheme of vertical multi-subregion space discretization [1] is used to enhance the numerical accuracy. The recursive formulation is extended to model composite substrates which is aimed at reducing the unwanted coupling among different lines in M(H)MIC's and high-speed interconnects. Numerical results are shown for both quasistatic and hybrid-mode analyses. Results of multiple strips on a composite uniaxial anisotropic substrate are also presented.

In this paper, coupled-mode equations for general bi-anisotropic waveguides with perfect electrically conducting (PEC) walls are studied and a set of rigorous expressions is obtained. The features of these equations are discussed and applications to circular/rectangular Faraday chiral and chiral waveguides are demonstrated. Comparisons between Faraday chiral, chiral, and ferrite-filled waveguides are also given.

A quasi-planar structure called Channelized Coplanar Waveguide (CCPW) is proposed for wideband applications of integrated microwave and millimeter-wave circuits. Compared with the conventional coplanar waveguides, the novel transmission line has a narrow metallic notch channel located underneath the main guiding part, which is able to provide direct grounding equalization without resorting to via-holes or the use of air-bridges. In addition, an electrically shielding condition, based on the theoretical principle of the nonradiative dielectric waveguide, is proposed to suppress radiation losses and reduce leaky-wave propagation in conjunction with the umbilical channel. Some interesting phenomenons regarding the electrically shielding condition are experimentally observed. One attractive feature of the proposed CCPW is its ability to drive higher-order modes towards higher frequency range, and therefore demonstrates a potential for wideband applications. A method of lines with vertical discretization scheme is used to accurately determine dispersion characteristics of the proposed CCPW and influence on mode propagation includin higher-order modes. Theoretical results of dispersion are verified experimentally over large frequency band of interest.

A method-of-lines based technique is presented for efficiently analyzing propagation problems of planar integrated circuits. A scheme of vertical multi-subregion space discretization is used to enhance numerical accuracy by improving most of the edge singularity on metallic conductors. On the other hand, this proposed approach is able to not only handle very narrow strips/very large slots topology or vice-versa, but also simulate exactly bilaterally unbounded structures with possible segmented multilayers. Numerical results including convergence characteristics are demonstrated for both quasi-static and hybrid-mode analysis. Comparison with other publications validates this novel algorithm.

Background: Conventional clinical detection methods such as CT, urine cytology, and ureteroscopy display low sensitivity and/or are invasive in the diagnosis of upper tract urinary carcinoma (UTUC), a factor precluding their use. Previous studies on urine biopsy have not shown satisfactory sensitivity and specificity in the application of both gene mutation or gene methylation panels. Therefore, these unfavorable factors call for an urgent need for a sensitive and non-invasive method for the diagnosis of UTUC. Methods: In this study, a total of 161 hematuria patients were enrolled with (n = 69) or without (n = 92) UTUC. High-throughput sequencing of 17 genes and methylation analysis for ONECUT2 CpG sites were combined as a liquid biopsy test panel. Further, a logistic regression prediction model that contained several significant features was used to evaluate the risk of UTUC in these patients. Results: In total, 86 UTUC− and 64 UTUC+ case samples were enrolled for the analysis. A logistic regression analysis of significant features including age, the mutation status of TERT promoter, and ONECUT2 methylation level resulted in an optimal model with a sensitivity of 94.0%, a specificity of 93.1%, the positive predictive value of 92.2% and a negative predictive value of 94.7%. Notably, the area under the curve (AUC) was 0.957 in the training dataset while internal validation produced an AUC of 0.962. It is worth noting that during follow-up, a patient diagnosed with ureteral inflammation at the time of diagnosis exhibiting both positive mutation and methylation test results was diagnosed with ureteral carcinoma 17 months after his enrollment. Conclusion: This work utilized the epigenetic biomarker ONECUT2 for the first time in the detection of UTUC and discovered its superior performance. To improve its sensitivity, we combined the biomarker with high-throughput sequencing of 17 genes test. It was found that the selected logistic regression model diagnosed with ureteral cancer can evaluate upper tract urinary carcinoma risk of patients with hematuria and outperform other existing panels in providing clinical recommendations for the diagnosis of UTUC. Moreover, its high negative predictive value is conducive to rule to exclude patients without UTUC. [ABSTRACT FROM AUTHOR]

Background: To examine the impact of the Mayo adhesive probability (MAP) score on the surgical complexity of exposing the tumor during laparoscopic partial nephrectomy (LPN). Patients and Methods: Our study included 318 patients who underwent LPN from January 2017 to December 2018 at our institution. Patients were divided into a lower MAP score group (≤2, n = 172) and a higher MAP score group (≥3, n = 146). Perioperative outcomes were compared between the groups. The operative time was predominantly occupied by the dissection time and the warm ischemia time (WIT). Results: A higher MAP score was associated with a longer operative time (131 vs 110 minutes, p < 0.001) and longer dissection time (71 vs 54 minutes, p < 0.001), respectively. The estimated blood loss (EBL) increased in patients with a higher MAP score (50 vs 20 mL, p < 0.001). No significant difference was found with respect to the WIT (21 vs 20 minutes, p = 0.370). In the multivariate linear regression model, male gender (β = 11.199, p = 0.001), body mass index (β = 1.197, p = 0.008), and MAP score (β = 9.958, p = 0.002) were significantly associated with the prolongation of dissection time. Conclusions: The MAP score was significantly associated with the prolongation of dissection time during LPN. In addition, the EBL increased in patients with a higher MAP score. Therefore, the MAP score can predict surgical complexity of exposing the tumor in patients undergoing LPN. [ABSTRACT FROM AUTHOR]

The present study was aimed to examine whether icariin, a traditional Chinese medicine, could improve therapeutic effects of adipose derived mesenchymal stem cells (ADSCs) for diabetes-associated erectile dysfunction (DMED). DMED were induced in rats by intraperitoneal injection of streptozotocin and confirmed by erectile function measurement. Then, rats of diabetic ED were randomly divided to receive the treatment of saline, ADSCs, icariin or ADSCs combined with icariin respectively. Compared with the treatment by ADSCs or icariin alone, intracavernosum injection of ADSCs combined with the following daily gastric gavage of icariin significantly augmented the value of ICP and ICP/MAP (p<0.01). Meanwhile, the survival of transplanted ADSCs was much improved due to the application of icariin. Similarly, immunofluorescent staining analysis demonstrated that the improved erectile tissue structure by combination of ADSCs and icariin was significantly associated with the increased expression of endothelial markers (vWF) (p<0.01) and smooth muscle markers (α-SMA) (p<0.01). Furthermore, the structure changes in corpus cavernosum were further confirmed by the Masson’s trichrome staining. To explore the possible mechanism underlying icariin-enhanced therapeutic efficacy of MSCs, we employed an in vitro testing system by introducing H2O2 to imitate oxidative stress condition considering the oxidative environment faced by engrafted ADSCs and anti-oxidative capacity of icariin. In vitro, we found that the addition of icariin considerably reduced the apoptosis of ADSCs, and attenuated the intracellular reactive oxygen species (ROS), the superoxidase dismutase (SOD) activity and the lactate dehydrogenase (LDH). Subsequently, we examined the expression of apoptosis-related proteins and explored the potential signaling pathway through which icariin promoted the survival of ADSCs against oxidative stress. It was demonstrated that icariin significantly inhibited the upregulation of apoptosis-related proteins under oxidative condition, including Bax and cleaved caspase-3, while promoted the expression of anti-apoptotic factor BCL2. These effects were accompanied with the activation of signal molecules, PI3K/Akt and STAT3. The further signal protein inhibition assays exhibited that the suppression of STAT3 abrogated the icariin-mediated anti-apoptotic effects observed above, while did not influence the expression of PI3K/Akt. However, PI3K inhibition could abrogate icariin–mediated STAT3 activation and achieved a similar effect as STAT3 inhibition. Our results suggested that icariin was an effective adjuvant for enhancing ADSC-based therapy of DMEM, which may be ascribed to their protection of ADSCs against oxidative stress via the regulation of PI3K/Akt-STAT3 signal pathway. [ABSTRACT FROM AUTHOR]

ABSTRACT In this letter, the design of planar six-way and eight-way power dividers by interconnecting power dividers with two and three output ports is studied. Using this approach, equal ripples of input reflection (S11) within a wide pass band are obtained. The interconnecting lines are used as additional matching sections. The isolation resistors are selected to obtain the optimal output port matching and isolation performances. A prototype of compact, low loss, and wideband eight-way power divider is designed, fabricated, and measured. The simulation and measurement results are in good agreement. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:189-192, 2016 [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to investigate the safety and efficacy of a modified CO2 laser technique for circumcision in adult males as compared with the conventional dorsal-slit method. Background data: Circumcision is one of the most commonly performed surgeries in the world. Although present techniques produce a good long-term result, there is a continuing need to improve the safety and efficacy of the circumcision procedure. Materials and methods: Data were analyzed from a prospective randomized controlled clinical study comparing two different operative techniques for adult circumcision: the modified CO2 laser circumcision technique, and the conventional dorsal-slit technique. A total of 300 patients >18 years of age were recruited in this study. Several perioperative data, including age, indications, operation time, intraoperative blood loss, complications, and postoperative pain were analyzed. Differences between the CO2 laser technique and the conventional technique were compared. Results: There was no statistically significant difference in age distribution and indications between the two groups. Compared with the conventional group, there were shorter operative time, less blood loss and lower postoperative complication rate in the laser group. The CO2 laser technique was associated with much less pain, as quantitated by a 10 point visual analogue scale (VAS) pain score at both 1 day and 7 days postoperatively. Conclusions: The modified CO2 laser technique that we introduced offers a simple, safe, faster, and effective alternative method to the conventional technique in adult male circumcision, with decreased blood loss, pain, and complications. [ABSTRACT FROM AUTHOR]

In this paper, the design of multiway power dividers by interconnecting power dividers with fewer output ports is studied by transforming them into multisection stepped-impedance transformers. By using this approach, it is easy to design multiway power dividers with required equal ripples of input reflection (S11) within a wide passband. The interconnecting lines can be used as additional matching sections to improve the input matching. General properties of this type of multiway power dividers can be easily obtained. Design of multiway power divider with required input reflection level can be readily performed by using the published data and tables of stepped-impedance transformer in the literature. Both even- and odd-mode analyses are performed to obtain the optimal isolation resistor values. A prototype of a wideband four-way power divider with a rhombic architecture is designed, fabricated, and measured. Simulation and measurement results are in good agreement and validate the proposed approach. [ABSTRACT FROM PUBLISHER]

Physical layer of cognitive-wave-radio receiver is investigated to identify interference signals, by spectrum sensing, in the presence of received QPSK data at 20 Mbps. The investigated cognitive-wave-radio receiver structure is based on existing wave radio physical layer (six-port receiver interferometer) adapted for the receiver data active cancellation. For active cancellation of the received digital data, four outputs of the standard wave radio receiver are used in conjunction with three 'single pole double throw' switches providing a single output of the 'zero state time interval' for spectrum sensing of the interference signal. Two interference signals were tested: a 7-dBm amplitude modulated interference and a wide band white noise with 0.01 mW/MHz. The microwave carrier of the QPSK signal is set at an amplitude of 16 dBm and a carrier frequency of 3.5 GHz. Once the interference signal spectrum is identified, the QPSK data are transmitted through the available channel. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:195-200, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25670 [ABSTRACT FROM AUTHOR]

A new SPDR design approach is proposed. The receiver contains an RF discriminator, power detectors, a signal level comparison circuit, a decoder, and data and carrier recovery circuits for BPSK and QPSK signals. The new receiver operates solely on analog circuits, and the proposed design is validated with circuit and system simulations of an RF discriminator and a Costas-type phase-locked loop, demonstration of a demodulator at 2.4 GHz, and MMIC fabrication of an RF discriminator at 15 GHz. The new design approach offers interesting possibilities to achieve SPDR-on-a-chip. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 25: 356–360, 2000. [ABSTRACT FROM AUTHOR]

In this paper, a four-port digital millimetric receiver (FP/DMR) is studied in detail. The FP/DMR is achieved by eliminating one of the output ports and the reference port of an ordinary six-port junction in the digital millimetric receiver proposed earlier. This paper provides the principle of operation of FP/DMR, its real time or “on-line” calibration methods, and a comparison with a traditional quadrature I/Q receiver. The principle of operation of the FP/DMR can also be used at lower frequencies (e.g., in the L-band) whenever mass-market applications demand the lowest possible receiver costs. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 22: 350–355, 1999 [ABSTRACT FROM AUTHOR]

In this paper, a new approach to the real-time calibration of a six-port receiver (SPR) by averaging the received QPSK signals is proposed. At first, the S-parameters/Qi points of the six-port are calculated from the average of the outputs of the six-port power detectors, and then calibration parameters of the six-port receiver are computed. Simulations on SPW verified this proposed approach. Error analysis with nonideal QPSK standard signals used in the calibration procedure is also performed. This proposed method of calibration has a clear physical meaning, and gives accurate calibration coefficients, even for very poor-quality six-port junctions. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 346–351, 1999. [ABSTRACT FROM AUTHOR]

In this paper, a study of the simplification of real-time calibration of six-port receivers (SPRs) is given. A simple, real-time calibration procedure is proposed using the incoming QPSK signal as the calibration standard. Only two systems of four linear equations are necessary to be solved in the calculation of the calibration parameters. This calibration procedure is especially suitable for QPSK reception. Modulation errors will be cancelled if the received signal is selected for the calibration standards. SPW simulation results of 64 QAM signal reception validate the proposed calibration procedure. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 20: 318–322, 1999. [ABSTRACT FROM AUTHOR]

In this paper two simple and effective methods are presented for solving electromagnetic problems of rectangular waveguides, loaded with lossy dielectrics. The procedures are demonstrated and the accuracy is shown for waveguides with three different types of dielectric filling. [ABSTRACT FROM AUTHOR]

Electromagnetic waves in magnetized (gyromagnetic) ferrite spheres are investigated by using coupled wave theory. Fields are expressed by means of superposition of modes in isotropic case. Some basic rules are obtained and some numerical results are calculated, which are in good agreement with experiments. [ABSTRACT FROM AUTHOR]

In this paper some simple and effective methods are presented for solving electromagnetic problems of dielectric-loaded rectangular waveguides. The procedures are demonstrated and the accuracy is shown for waveguides with three different types of dielectric filling. [ABSTRACT FROM AUTHOR]

In this paper, the problem of local oscillator (LO) leakage to the input of a digital millimetric six-port receiver (SPR) is studied in detail. It is shown that this leakage can be considered as an additional in-band interference signal to the SPR that alters the output signals of the six-port discriminator as if the Qi points of the six-port junction are modified. Analysis and simulation results of this leakage are provided, and methods to overcome its effects for real-time operation are given. Improvements in the performance of a six-port junction in the presence of LO leakage are evaluated. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 19: 27–34, 1998. [ABSTRACT FROM AUTHOR]

In this paper, the nonlinear cross-modulation noise/interference arising from channel filtering and leakage in a six-port digital millimetric receiver (DMR) is studied in detail. The in-band noise/interference arises from strong noise/interference outside the receiving bandwidth, and will deteriorate the bit-error rate (BER). Analysis and simulation results of this effect are provided, and results on methods of its suppression are also given. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 17: 386–394, 1998. [ABSTRACT FROM AUTHOR]

In this paper an improved method is presented for waveguides loaded with lossy dielectric or magnetic materials. The accuracy of this method is shown for waveguides with three different types of filling. [ABSTRACT FROM AUTHOR]

Abstract A stepped short tube orifice (SSTO) consisting of two serial-connected short tube orifices with different diameters was recently proposed as an inexpensive expansion device in air conditioning/heat pump system. In this study, a split air conditioner/heat pump employing stepped short tube orifices was investigated experimentally to further evaluate the performance of the SSTO air conditioner/heat pump system. At first, the mass flow rate of refrigerant (R-22) through stepped short tube orifices and an original expansion device were studied in both cooling and heating flow directions to verify the throttling capacity difference of these two type of expansion devices. Then, the influence of geometric sizes of SSTOs, refrigerant charge amount and environment temperature on the performance of the SSTO air conditioner/heat pump were examined. Besides, the performance of the SSTO systems also compared with that of the original system with capillary tube under nominal and varying conditions. The results show that 18# SSTO system performed the best COP among all the five SSTO systems and one original system in nominal cooling and heating conditions, though the heating capacity of the 18# SSTO system was slightly inferior to that of the original system due to the insufficient throttling capacity of 18# SSTO in heating mode. [ABSTRACT FROM AUTHOR]

Purpose: To compare the treatment outcomes of robotic retroperitoneal lymph node dissection (R-RPLND) versus laparoscopic RPLND (L-RPLND) for clinical stage I non-seminomatous germ cell testicular tumors (NSGCTs).Materials and Methods: We retrospectively reviewed the data of patients with stage I NSGCTs who underwent robotic or laparoscopic RPLND between 2008 and 2017. Perioperative data and oncologic outcomes were reviewed and compared between the two groups. Progression-free survival was analyzed using Kaplan-Meier survival curves and compared between two groups.Results: A total of 31 and 28 patients underwent R-RPLND and L-RPLND respectively. The preoperative characteristics of the patients were comparable in the two groups. Patients in R-RPLND group had significantly shorter median operative time (140 vs. 175 minutes, P < .001), a shorter median duration to surgical drain removal (2 vs. 4 days, P = .002) and a shorter median postoperative hospital stay (5 vs. 6 days, P = .001). There were no statistical differences in intra- and post-operative complication rate between the groups and the oncologic outcomes were similar in the two groups.Conclusion: In expert hands, R-RPLND and L-RPLND were comparable in oncological parameter and morbidity rate; R-RPLND showed superiority in operation duration, median days to surgical drain removal and postoperative hospital stay for stage I NSGCTs. Multicenter and randomized studies with good power of study and sufficient follow-up duration are required to validate our result. [ABSTRACT FROM AUTHOR]