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Background Hepatocellular carcinoma (HCC) is the sixth most common malignant tumor and second most common cause of tumor-related deaths worldwide. Activated platelets play a prominent role in tumor. Platelet distribution width (PDW) indicates platelets activation and is altered in malignancies. The aim of this study was to explore the prognostic value of PDW for overall survival (OS) in HCC patients. Methods We retrospectively reviewed 273 HCC patients at a single institution from 2010 to 2014. The relationship between PDW and clinicopathological characteristics was analyzed. Kaplan-Meier curves and multivariate Cox regression analyses were used to evaluate the relationship of PDW with OS. Results Low PDW levels were observed in 127 (46.5%) out of 273 patients. A significant correlation was found between PDW and liver cirrhosis. Median follow-up was 36 months, survival curves revealed that the patients with increased PDW had significantly shorter survival time than those with normal PDW (p= 0.001). Cox regression analysis demonstrated that PDW was an independent prognostic factor for overall survival (hazard ratio, 2.464; 95% confidence interval [CI], 1.402-4.330, p= 0.001). Conclusion PDW is significantly associated with OS in HCC. This result suggests activated platelet may affect clinical outcome and warrant continued investigation.

Background Platelets play a crucial role in breast cancer (BC) progression and metastases. Mean platelet volume (MPV) is an indicator of platelet activation. The aim of the present study was to assess whether there is a difference in MPV between patients with metastatic BC with liver metastases and those with BC without liver metastases. Methods Between January 2014 and December 2017, 211 metastatic BC patients with synchronous liver metastases and 215 BC patients without metastases were retrospectively analyzed. Patients' clinicopathological characteristics data were collected. Results MPV levels were reduced in patients with liver metastases compared with those in patients without liver metastases. There were significant differences in MPV levels according to liver metastases status both in premenopausal and in postmenopausal non-TNBC or non-HER2+ patients. Moreover, in postmenopausal HER2+ or TNBC patients, MPV levels were lower in patients with liver metastases compared with those in patients without liver metastases. In the group with non-liver metastasis, platelet distribution width was significantly associated with tumor N stage. In addition, the prevalence of BC liver metastases decreased as MPV quartiles increased. After adjusting for other risk factors, the odds ratios for liver metastases according to MPV quartiles were 1.000, 0.267 (0.134-0.530), 0.072 (0.034-0.152), and 0.137 (0.066-0.281), respectively. Conclusion MPV is reduced in BC patients with liver metastases compared with that in BC patients without metastases. Moreover, MPV is independently associated with the presence of liver metastases.

The current study observed the percentage of peripheral blood (PB) CD4+CD25+ regulatory T cells (Tregs) and the influence of CD4+CD25+ Tregs on the proliferation of naïve CD4 T cells in patients with hyperthyroidism. Furthermore, preliminary discussions are presented on the action mechanism of CD4+CD25+ Tregs on hyperthyroidism attacks. The present study identified that compared with the percentage of PB CD4+CD25+ Tregs in healthy control subjects, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism (P>0.05). For patients with hyperthyroidism, CD4+CD25+ Tregs exhibited significantly reduced inhibition of the proliferation of naïve CD4 T cells and decreased secretion capacity on the cytokines of CD4 T cells, compared with those of healthy control subjects (P0.05). In the patients with hyperthyroidism, following treatment, CD4+CD25+ Tregs exhibited significantly increased inhibition of the proliferation of naïve CD4 T cells and increased secretion capacity of CD4 T cell cytokines, compared with those of the patients with hyperthyroidism prior to treatment (P

Background. The gut microbiota is involved in the occurrence and development of chronic liver diseases. Zonulin is considered a marker of intestinal permeability. The purpose of this study was to assess zonulin levels in patients with chronic hepatitis B (CHB), HBV-associated liver cirrhosis (LC), and HBV-associated hepatocellular carcinoma (HCC). Materials and Methods. The study population consisted of 90 HBV-associated HCC patients, 90 HBV-associated LC patients, 90 CHB patients, and 90 healthy subjects. Serum levels of zonulin and AFP were determined. The diagnostic accuracy of each marker was evaluated using receiver operating characteristic (ROC) curve analysis (AUC). Results. Serum zonulin levels were significantly higher in patients with HCC than in patients with LC or CHB or healthy subjects (p<0.001). Moreover, the zonulin levels were increased in the advanced stage of LC and HCC. ROC curve analysis revealed that serum zonulin could be used to differentiate CHB from cirrhosis. In addition, the combination of zonulin and AFP exhibited a significantly larger AUC compared with zonulin or AFP alone. Conclusions. Serum zonulin levels were significantly increased both in LC and in HCC and correlated with the advanced stage of LC and HCC. Moreover, the combination of zonulin and AFP confers significant benefit to diagnostic accuracy in differentiating LC from HCC.

Novel wideband balanced bandpass filter with high selectivity and common-mode (CM) suppression is constructed with slotline resonator. When the intersection points of the microstrip feedline and slotline resonator are close to the midpoint of the slotline resonator, the coupling between the fundamental mode of the slotline resonator and microstrip feedline can be maximised, whereas the second mode can be suppressed. Making use of this feature, the third-order wideband filter with low insertion loss, wide upper-stopband and flat group delay is designed by using the slotline resonator and two quarter-wavelength microstrip resonators paralleled to the slotline resonator with tapped-line coupling at their short-circuited ends. Based on the third-order single-ended filter structure, a novel balanced filter with a 1 dB fractional bandwidth up to 72% is designed with low insertion loss and enhanced CM suppression. To improve the selectivity, the fifth-order wideband balanced filter with wide upper-stopband is designed with parallel coupling structure between two slotline resonators. The corresponding CM suppression is better than 42 dB within the whole differential mode passband. The wideband balanced filter is designed and fabricated, and good agreement between measurements and simulations is obtained.

The Accepted Manuscript version of this article (published on 6 June 2017) was withdrawn on 16 November 2017 at the request of the authors.

In this letter, a novel high selectivity and common-mode (CM) suppression wideband balanced microstrip passband filter (BPF) is proposed using the short stub centrally loaded short-ended resonators (SSCLSR). The odd-mode resonant frequency of the SSCLSR can be flexibly controlled by the short stub, whereas the even-mode one is fixed. First, the wideband single-ended BPF are designed based on the microstrip SSCLSR with the parallel coupled microstrip line input/output (I/O). Two transmission zeros near the passband edges can be generated due to the main path signal counteraction and source-loaded coupling. Further, the CM equivalent half circuits of the balanced BPF based on the wideband single-ended BPF are investigated in detail. Thus, a wideband balanced BPF with high CM suppression within the passband is designed, fabricated, and measured. Good agreement between simulated and measured results is obtained. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2940–2944, 2014

In this letter, a novel wideband balanced bandpass filter (BPF) with high selectivity and common-mode (CM) suppression is constructed with slotline resonator. When the intersection points of the microstrip feedline and slotline resonator are close to the midpoint of the slotline resonator, the coupling between the second mode and microstrip feedline can be suppressed. Making use of this feature, the wideband single-ended filter with wide upper-stopband performance is designed using the slotline resonators and two quarter-wavelength microstrip resonators paralleled to the slotline resonator with tapped-line coupling at their short-circuited ends. Further, high-selectivity fifth-order wideband single-ended filter and corresponding balanced BPF are designed with parallel coupling structures between two slotline resonators. The fifth-order wideband balanced filter is designed and fabricated, and good agreement between measurements and simulations is obtained. The measured CM suppressions are better than 54 dB within the whole differential-mode passband. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2998–3003, 2014

In this article, a compact diplexer is proposed using the U-shaped slotline resonator (U-SR) and dual-mode slotline resonator (DM-SR) for wideband and WLAN applications. The filter using the U-SR has three transmission poles in the passband and two transmission zeros near the passband edges. The wide upper-stopband can be realized for the second mode of the U-SR is well suppressed. The DM-SR has two resonant frequencies (odd- and even-modes) in the desired passband. And the odd-mode resonant frequency can be flexibly controlled by the slotline stub, whereas the even-mode one is fixed. Due to the main path signal counteraction and source-load coupling, the filter using the DM-SR possesses two transmission zeros in the upper-stopband. The mutual loading effect of two filters can generate new transmission zeros, which are mainly applied to improve the isolation. Compact size can be obtained without extra matching network. A diplexer prototype is designed, and good agreement can be obtained between measured and simulated results. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2480–2484, 2014

Taking a bridge of 160m long variable cross-section prestressed continuous curved box-girder as the research object and analyzing the cross-sectional design of axis with axial symmetrical or axial non-symmetrical to research the structure forces change of the upper part of bridge in different curvature. In order to test and verify the variable cross-section of prestressed continuous curved box-girder bridge is safe and reliable via cross-sectional design with axial symmetrical instead of axial non-symtrical within a radius of curvature of the interval. Creating the straight bridge and curved bridge models with different radius of curvature in same span by Midas/Civil to compare their structure forces.

In this letter, a novel compact dual-band microstrip bandpass filter (BPF) with multiple transmission zeros is proposed using the third-order interdigital structure and dual-mode short stub center-loaded resonator (DSLR) for wideband and WLAN applications. The high impedance feedline for the filter with the folded DSLR can function as the quarter-wavelength resonator (QWR) for the third-order interdigital filter. Meanwhile, the folded DSLR can be adopted without an evident increase of the size of the compact interdigital filter. Three transmission zeros between two passbands and in the lower- and upper-stopbands can be created due to the cross coupling between two high impedance feedlines as well as between the input and output, and the intrinsic characteristic of the DSLR. Further, two inverse QWR coupling short stubs with different size loaded in the 50 Ω feedlines can generate four transmission zeros to improve the isolation and deepen the stopband. Finally, a compact dual-band BPF prototype is designed, and good agreement can be obtained between measured and simulated results.

A new compact, low insertion loss, and wide stopband balanced bandpass filter (BPF) with two common-mode (CM) transmission zeros within the differential-mode (DM) passband is designed in this article. The DM filtering topology is formed by two quarter-wavelength resonators and a short stub loaded source-load coupling structure which can generate new transmission zeros to improve the selectivity and suppress the harmonic to widen the stopband. The center-loaded step-impedance open stub can be applied to misalign two CM fundamental resonant frequencies, meanwhile adjust one CM transmission zero to the DM passband. To enhance the CM suppression within the DM passband, another CM transmission zero is created by the folded stub loaded in the 50- input feedline which creates the first DM transmission zero located at 2 f0d ( f0d is the center frequency of DM passband) and has little effect on the DM in-band and lower-stopband performance. Finally, a high CM suppression balanced BPF prototype for WLAN application is designed and fabricated. The simulated and measured results show a good agreement. (c) 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:135-141, 2014

A compact, high selectivity and good common-mode (CM) suppression balanced broadband bandpass filter (BPF) is proposed using hybrid hairpin-interdigital structure. Under the differential-mode (DM) excitation, the filtering topology is formed by n + 1 quarter-wavelength resonators (QWRs) and n hairpin resonators (HRs) instead of QWRs with coupled-line I/O coupling structure. But, the DM circuit still maintains high selectivity and broadband characteristics of the interdigital BPF. By reasonably choosing the coupling length and the length of the HR, the balanced BPF can not only obtain the desired DM frequency response, but the CM harmonic generated by the HR can be well suppressed by the CM transmission zero created by the coupling between the HR and half-wavelength resonator (HWR). No via-hole ground for the balanced broadband BPF is required, reducing the implementation complexity. Finally, the third-, fifth-, and seventh-order balanced broadband BPF prototypes are designed and fabricated, and the simula...

In this article, a high-isolation microstrip diplexer with enhanced stopband characteristics is presented for GSM and Wireless Local Area Network (WLAN) application. The proposed diplexer consists of two compact bandpass filters (BPFs) using short-circuit centered stepped impedance resonators (SCSIRs), operated at 1.8 and 2.45 GHz, respectively. Due to the intrinsic characteristics of the SCSIRs, multiple transmission zeros can be generated for high selectivity and wide upper-stopband. By locating the transmission zero of one channel at the passband of the other channel, and utilizing good impedance matching between two BPFs, high output isolation can be achieved. A microstrip diplexer prototype is designed and fabricated. The upper-stopband of two channels in experiment is extended up to 10.2 GHz with an insertion loss larger than 28 dB. Meanwhile, the measured isolation greater than 48 dB in GSM passband and more than 52 dB in WLAN passband is achieved between two channels. A satisfactory agreement between the simulated and measured results validates the proposed configuration. The size without the 50-Ω feed lines is only 0.250λ×0.112λ in which λ is the guided wavelength at 1.8 GHz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2990–2993, 2013

In this paper, a general synthesis method is proposed for the design of multi-frequency impedance transformers (MFITs) for arbitrary frequency-dependent complex loads (FDCLs) by adopting the concept of multi-frequency inverters (MFIs). An MFI, which is placed between two susceptance blocks, is constructed with a transmission line and two-side multi-frequency susceptances (MFSs), whose values at multiple frequencies are independently specified. By merging neighboring susceptances, we get a very simple Pi-shaped topology of MFITs, which in theory has no limitation on the number of matching frequencies. The MFS blocks are realized with one or more parallel shunt stubs, providing needed susceptance values at several specified frequencies. A genetic algorithm is used in extracting the circuit parameters of the parallel stubs. Several dual-, triple-, and quad-frequency impedance transformers for FDCLs are designed for illustrating the design methods. Experiment and simulation results are compared with good agreement, validating the feasibility of the theory. The designed impedance transformers are concise in circuit and compact in dimensions.

In this article, a new compact and high selectivity broadband microstrip bandpass filter (BPF) is proposed using one folded half-wavelength resonator (FHWR) in the middle and two quarter-wavelength resonators (QWRs). Due to the cross coupling between the source/load and FHWR, four transmission zeros can be created in the lower- and upper-stopband. The transmission zero generated by the coupling between the QWR and parallel-coupling feedline can sharpen the skirt and suppress the first harmonic of the FHWR. To verify the design concept, a microstrip BPF with 1-dB fractional bandwidth (FBW) of 61% centered at 3 GHz is designed and fabricated. Measured results show low insertion loss and flat group delay in the entire passband as well as high out-band rejection. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2501–2504, 2013

In this paper, a new compact microstrip balanced bandpass filter (BPF) and balanced-to-balanced diplexer are designed with high selectivity and common-mode (CM) suppression. The equivalent differential-mode (DM) and CM half-circuits of the proposed balanced BPF and balanced-to-balanced diplexer are analyzed in detail. Under the DM excitation, the filtering topology is formed by two coupling quarter-wavelength resonators (QWR) and source-load short-ended feedlines. Two transmission zeros can be generated near the DM passband edge to achieve high selectivity. Under the CM excitation, the transmission zero generated by the coupling between the QWR and short-ended feedline can be adjusted by the shorted stub loaded at the center to the DM passband. Moreover, the mutual loading effect of the filters with two coupling uniform resonators is approximately equivalent to a uniform resonator coupling shorted stub. Hence, the mutual loading effect of two balanced BPFs can generate new transmission zeros to deepen the...

In this article, a novel compact and high performance microstrip diplexer is designed for global position system (GPS) and wireless local area network (WLAN) applications. The compact diplexer consists of two filters with short centered stepped impedance resonators (SCSIRs) and quarter-wavelength resonators (QWRs), operated at 1.575 GHz and 5.8 GHz, respectively. Due to the intrinsic characteristics and mutual loading effect of two filters, multiple transmission zeros can be generated to achieve sharp skirt, wide stopband, and high isolation of the diplexer. Moreover, more compact size can be obtained without the extra junction matching. Finally, a microstrip diplexer with 1 dB absolute bandwidth 100 MHz for GPS channel and 1 dB fractional bandwidth (FBW) of 3.45% at 5.8 GHz for WLAN channel is designed and fabricated. The simulated and measured results show a better agreement and validate the proposed theory. The size without the 50 Ω feedline is only 0.156 λg × 0.103λg, in which λg is the guided wavelength at 1.575 GHz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1233–1237, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27550

In this paper, a compact and high isolation microstrip diplexer is designed for broadband and wireless local area network (WLAN) application, simultaneously. The bandpass fllter (BPF) for broadband channel is formed by three-coupled-line structure and two short stubs with difierent size loaded in 50› feed lines, and the BPF for WLAN channel consists of two coupling quarter-wavelength resonators (QWR) and one open stub loaded in short parallel-coupling feed structure. Multiple transmission zeros can be generated due to their intrinsic characteristics, so the broadband BPF with sharp skirt and wide upper-stopband performance and the WLAN BPF with sharp roll-ofi and lower-stopband characteristic can be realized. The tapped stub not only can generate new transmission zeros to deepen the stopband, but also can connect other BPF as an its part without deterioration of in-band performance. Hence, a compact microstrip diplexer combines of two BPFs without the extra junction matching network. The mutual loading efiect approximately equivalent to a coupled QWR can also generate new transmission zero at the passband edge to improve the isolation. A microstrip diplexer with the 3dB fractional bandwidths (FBW) of 80% for broadband channel and 5% for WLAN channel is designed and fabricated. Good agreement between the simulated and measured results is observed.

We propose ultrathin Huygens metasurfaces to control transmission amplitudes and phases of electromagnetic waves independently, in which each unit cell is comprised of an electric dipole and a magnetic dipole. By altering the electric and magnetic responses of unit cells, arbitrary complex transmission coefficients with modulus values smaller than 0.85 are obtained. Two Huygens metasurfaces capable of controlling the diffraction orders are designed and fabricated by modulating the distributions of the complex transmission coefficients. More complicated functions such as holographic imaging can also be accomplished by using the proposed Huygens metasurfaces.

In this paper, an ultra-wideband and polarization-independent metasurface for radar cross section (RCS) reduction is proposed. The unit cell of the metasurface operates in a linear cross-polarization scheme in a broad band. The phase and amplitude of cross-polarized reflection can be separately controlled by its geometry and rotation angle. Based on the diffuse reflection theory, a 3-bit coding metasurface is designed to reduce the RCS in an ultra-wide band. The wideband property of the metasurface benefits from the wideband cross polarization conversion and flexible phase modulation. In addition, the polarization-independent feature of the metasurface is achieved by tailoring the rotation angle of each element. Both the simulated and measured results demonstrate that the proposed metasurface can reduce the RCS significantly in an ultra-wide frequency band for both normal and oblique incidences, which makes it promising in the applications such as electromagnetic cloaking.

In this article, a novel tri-band wideband microstrip bandpass filter (BPF) with compact size and high selectivity is proposed using three sets of resonators, that is, λ/4 resonators, short-stub loaded resonator, and λ/2 resonators.Each of the resonators can not only separately generate one passband, but also mainly control the passband performance. Due to the extended feed lines, parasitic coupling and intrinsic characteristics of the resonators, multiple transmission zeros can be created to improve the selectivity. A tri-band wideband microstrip BPF centered at 2.0, 3.6, and 5.5 GHz is designed, and the predicted results are confirmed experimentally. The size is only 0.156 × 0.303 λg in which λg is the guided wavelength at 2.0 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:258–261, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27334

A tri-band microstrip bandpass filter (BPF) with compact size and high selectivity is presented by using the stub-loaded resonator (SLR) and quarter-wavelength stepped-impedance resonator (SIR). The quarter-wavelength SIR is designed for the first and third passband and the SLR mainly controls second passband performance, so three passband frequencies can be flexibly tuned. Because of the intrinsic characteristics of the resonators and source-load coupling, multiple transmission zeros can be created to improve the selectivity. Finally, a tri-band BPF prototype located at 0.98 GHz (FRID application), 3.6 GHz (Wimax application), and 5.8 GHz (WLAN application) is designed. Measurement results agree well with the full-wave EM simulated results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:212–215, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27247

In this letter, a novel compact and high selectivity dual-mode dual-band microstrip bandpass filter (BPF) with quarter-wavelength resonator and stub-loaded resonator is proposed using extended feed lines.Either of the SIRs cannot only separately generate one passband but also mainly control the passband performance. Due to the extended feed lines, parasitic coupling and intrinsic characteristics of the resonators, multiple transmission zeros can be created to improve the selectivity. Meanwhile, the BPF can obtain compact size due to the folded resonators and feed lines. A dual-mode dual-band BPF with the fractional bandwidth 15.6 and 6.4% is designed and fabricated. The simulated and measured results show a better agreement and validate the proposed theory. The size is only 0.185λg × 0.130λg in which λgis the guided wavelength at the first passband center frequency. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 2702:2705, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27211

A novel high selectivity dual-wideband microstrip bandpass filter (BPF) with two triple-mode stub-loaded stepped-impedance resonators (SIRs) is proposed in this letter. Either of the SIRs can not only separately generate one passband but also control the passband performance. Because of the intrinsic characteristics of the SIRs, four transmission zeros can be generated to improve the selectivity. A dual-wideband filter with the fractional bandwidth 15.4% and 10.2% is designed and fabricated. The dual-wideband filter is evaluated by experiment and simulation with good agreement. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2851–2854, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26371

A broadband bandpass filter (BPF) with compact size and high selectivity performances is proposed using the dual-mode folded-T-type resonator and the identical short stub loaded parallel-coupling feed structure.The resonator can generate one even-mode and one odd-mode in the desired band. Two resonant frequencies can be adjusted easily to satisfy the bandwidth of the BPF. The feed structure can generate four transmission zeros near the cutoff frequencies and in the stopband, leading to sharp skirt and deep stopband. One filter prototype with the fractional bandwidth of 58.89% is fabricated for experimental verification of the predicted results. The size for the resonator is only 0.156λg × 0.303λg in which λg is the guided wavelength of 50 Ω microstrip line at the center frequency. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26108

In this article, a novel compact broadband microstrip bandpass filter with high selectivity and wide upper-stopband performance is proposed using quintuple-mode stub-loaded resonator. The proposed resonator can generate two odd-modes and three even-modes in the desired band. The open stub and short-circuited stub at its central plane can not only specially control the even-mode resonant frequencies, whereas the odd-mode ones are fixed, but also generate two transmission zeros near the upper and lower cut-off frequencies, leading to high rejection skirt. Two identical impedance-stepped open stubs are mainly applied to adjust the high resonant modes (fm4, fm5) into desired passband and excite one additional transmission zero to deepen the upper-stopband. A quintuple-mode broadband filter with the fractional bandwidth better than 64% is simulated, fabricated, and measured. The EM simulated and measured results are presented and excellent agreement is obtained. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:799–803, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25849

This paper presents a tri-band bandpass filter in which a dual-band bandpass filter (BPF) and a single-band bandstop filter (BSF) are integrated into a single circuit of short length. The dual-band BPF contains several two-section stepped-impedance stubs which are mounted onto a main transmission line. The BSFs are constructed using capacitor-loaded shunt stubs which are connected by transmission lines. After circuit embedding, one wide passband of the dual-band BPF is converted into two passbands by the stopband of the BSF, resulting in a total of three passbands. A prototype tri-band filter is designed according to prescribed specifications: the required passbands are 1–1.4, 1.8–2.0 and 2.42–2.66 GHz with return loss above 10 dB, while the expected isolations between bands are above 40 dB. Optimization method is adopted for extracting the circuit parameters. The simulated and measured results are compared, and good features such as low insertion loss and high isolation are demonstrated.

A highly miniaturized simplified composite right/left handed (SCRLH) mushroom zeroth-order resonator (MZOR) is proposed for bandpass filter (BPF) design. By introducing the U slot etched around the metallic via, more flexible selection of the shunt inductance value can be achieved compared with the original one. As the length of U -slot increased, zeroth-order resonant frequency of the MZOR decreased, even 88% size reduction can be achieved. Finally, a bandpass filter based on the proposed MZOR is designed, fabricated and measured. The simulated and measured results are presented and good agreement is obtained.

A compact dual-band bandpass filter (BPF) with a slotline resonator (SR) and a short stub centre-loaded microstrip resonator (SMR) is proposed for wideband and wireless local area network (WLAN) applications. The high-impedance microstrip feedlines for the filter with the SMR can function as the quarter-wavelength resonators for the filter with the SR to realise a wideband passband. Owing to the source–load coupling, the loaded short stub and the intrinsic characteristics of the SMR, three transmission zeros can be created to improve selectivity and isolation. Compact size can be obtained by adopting the folded SR and folded SMR inserted between the arms of the SR. A compact dual-band BPF for wideband and WLAN applications is simulated and measured, and good agreement can be obtained between the measured and simulated results.

We aim to investigate the pathological temporospatial characteristics of brain cell injury in the perihematomal areas. Brain autopsy samples from 44 consecutive cases of intracerebral hemorrhage were processed and analyzed following immunohistochemical staining for neurofilament (NF) and glial fibrillary acidic protein (GFAP). NF and GFAP positive cells were scored and graded according to the distance from the hematoma and the time from the onset of hematoma formation. The tissues from the same region on the contralateral side of the brain were used as controls. Neurons in the perihematomal areas exhibited pyknosis or swollen necrosis, while astrocytes were swollen. Morphological abnormalities pertaining to NF appearance were attenuated with increasing distance from the hematoma wall, but were exacerbated with prolonged bleeding time. The level of NF staining abnormality was positively correlated with time from the onset of hematoma within 7 days of intracerebral hemorrhage. In contrast, the intensity of GFAP staining was negatively correlated with time from the onset of hematoma formation. This immunoreactivity was significantly higher closer to hematoma. Taken together, these data indicate that pathological alterations in neurons and astrocytes in the perihematomal area change with time from the onset of hematoma formation.

A novel compact bandpass filter (BPF) with good in band and wide upper-stopband performances is realized using open stub loaded dual-mode resonator.The resonator generates two operating modes in the desired band and the even-mode resonance frequency can be flexibly controlled by the disc-shaped open stub at central plane, whereas the odd-mode one is fixed. By simply adjusting the dimension of the disc-shaped open stub, the even resonant mode falls down and works together with the odd mode to form a BPF. Two other pairs of open stubs are mainly applied to suppress the high harmonic resonant modes and obtain good match, respectively. Experimental results of the fabricated filter show good agreement with the simulated results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2185–2188, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25453

In this paper, a novel compact quintuple-mode UWB bandpass fllter (BPF) with sharp rejection skirt and wide upper- stopband performances is realized using stub-loaded multiple-mode resonator (MMR). The proposed resonator is formed by attaching two pairs of circular impedance-stepped open stubs in shunt and a pair of short-circuited stubs to high impedance microstrip line. By simply adjusting the radius of circular impedance-stepped open stubs and the lengths of short-circuited stubs, the flrst flve resonant modes of the resonator can be roughly allocated within the 3.1{10.6GHz UWB band meanwhile the high resonant modes in the upper-stopband can be suppressed. The short stubs in pairs can generate two transmission zeros near the lower and upper cut-ofi frequencies, leading to sharper rejection skirt outside the desired passband. Finally, a quintuple- mode UWB BPF is designed and fabricated, and the measured results demonstrate the feasibility of the design process.

In this letter, a novel high selectivity microstrip fllter with source-loaded coupling is proposed using the dual-mode resonator. The resonator can generate one odd mode and one even mode in the desired band. The folded stepped-impedance open stub at the central plane can control the even mode resonant frequencies, whereas the odd mode ones are flxed. A transmission zero is created near the lower cut-ofi frequency due to the main path signal counteraction. Two additional transmission zeros attributed to source-loaded coupling are generated near the upper cut-ofi frequency and in the upper-stopband. A dual- mode fllter prototype is simulated, fabricated and measured. The EM simulated and measured results are presented and excellent agreement is obtained.

A general 6-term error model is presented for the calibration of the three-port vector network analyzer (VNA). In the general two-port 6-term error model where port i (i ≤ 3) is the signal source, and other unexcited ports are regarded as a general port. The nodes and coefficients related with the general port are replaced by the complex vectors and square matrixes. With every port connected to the power source, the actual S-parameters of the three-port device can be finally solved from the general 6-term error model. Experiment results of a three-port device attest the good performance of the general 6-term error model.

In this letter, a novel compact wideband bandpass fllter (BPF) is proposed using quadruple-mode resonator formed by attaching a short-circuited stub at the center plane and two identical impedance-stepped open stubs to high impedance microstrip line. The resonator can generate two even-modes fm1, fm3 and two odd-modes fm2, fm4 in the desired band. The even-mode resonant frequencies can be ∞exibly controlled by the short-circuited stub, whereas the odd-mode ones are flxed. When the open stubs are attached to the center plane nearby, they can be mainly applied to adjust fm3, fm4 into desired passband as the high odd-mode and even-mode resonant frequencies are vulnerable to their electronic lengths. Two transmission zeros near the lower and upper cut-ofi frequencies are separately created by the short-circuited stub and interdigital feeding lines, leading to a high rejection skirt. A wideband BPF with the fractional bandwidth 64% is simulated, fabricated and measured. The measured results agree well with the EM simulations.

Novel compact microstrip quadruple-mode stub-loaded resonator and broadband bandpass fllter (BPF) are proposed in this letter. As a starting part of designing a quadruple-mode broadband BPF, the initial novel triple-mode open impedance-stepped stub loaded resonator characteristic is investigated to choose its proper dimensions. Based on these pre-determined dimensions of the triple- mode resonator, two identical short-circuited stubs are loaded against the impedance-stepped open stubs in the resonator to generate a tuned resonant mode and a transmission zero in lower stopband which leads to a high rejection skirt. A compact broadband BPF with the quadruple-mode resonator is simulated, fabricated and measured. The measured results agree well with the EM simulations.

A compact dual-mode open stub-loaded resonator and bandpass fllter (BPF) is proposed in this paper. The resonator, which is formed by attaching a disc-shaped open stub and circular open stubs in pairs to a high impedance microstrip line, generates two operating modes in the desired band, and the even-mode resonance frequency can be ∞exibly controlled by the disc-shaped open stub at central plane, whereas the odd-mode one is flxed. The four transmission zeros are created to sharpen the rejection skirt, suppress two high harmonic resonant modes and deepen upper-stopband, respectively. Experimental results of the dual-mode fllter which incorporates this resonator with parallel-coupled feed line with tuning stub at 5.8GHz show good agreement with the simulated ones. The size for the resonator is only 4:7 £ 3:4mm (0:29‚g £ 0:21‚g in which ‚g is the guided wavelength of 50› microstrip at 5.8GHz).

A miniaturized ultra-wideband (UWB) bandpass fllter (BPF) with U-slot etched around the metallic via in the ground is proposed based on a simplifled composite right/left-handed transmission line (SCRLH TL) structure. The U-slot etched in the ground makes it feasible to reduce the overall size. A demonstration of FCC standard UWB bandpass fllter (BPF) is designed, fabricated and measured. Very good agreement is shown between measurement and simulation.

In this letter, a compact and high selectivity broadband bandpass fllter (BPF) is proposed using the dual-mode folded-T-type resonator and the short stub loaded parallel-coupling feed structure. The resonator can generate one even-mode and one odd-mode in the desired band. Two resonant frequencies can be adjusted easily to satisfy the bandwidth of the BPF. A parallel-coupling feed structure with a cross coupling has been applied to generate two transmission zeros in the lower and upper stopband. Furthermore, the loaded short stub can create two transmission zeros near the upper cut-ofi frequency and in the upper stopband. Simultaneity, the transmission zero in the lower stopband moves towards the cut-ofi frequency. One fllter prototype with the fractional bandwidth 57% is fabricated for experimental veriflcation of the predicted results. The size for the resonator is only 0:156‚g£0:303‚g in which ‚g is the guided wavelength of 50› microstrip at the center frequency.

A 4-component compact 2-D finite-difference frequency-domain (FDFD) method is utilized for the analysis of dispersion characteristics of lossy circular metal waveguide. In the analysis, the surface-impedance boundary condition (SIBC) can be implemented as easy as that in 6-component method in literature. The phase constant and attenuation constant can be obtained as solution of eigen value problem for a given frequency. The results agree very well with the theoretical solutions.

A broadband random metasurface for Radar Cross Section (RCS) reduction is proposed in this paper. The metasurface is composed of double multi-folded loop elements. By adjusting the size of each element, different reflection phases are obtained. Thus the incident plane wave is scattered into arbitrary directions. In order to demonstrate the validity of the design, a random metasurface with a dimension of 480 mm×480 mm is constructed and simulated. For the normal incidence, the backward scattering can be reduced by 10 dB in the range of 7.8–14.1 GHz. The oblique incidence condition with the angle ranging from 10° to 30° is also investigated, in which the 7-dB bistatic RCS reduction can be obtained from 8 GHz to 14 GHz.

Purpose To analyze the reasons for the failure of the primary arteriovenous fistula surgery and explore preventive measures. Methods A total of 819 patients with end-stage renal disease were enrolled in the study. Autologous arteriovenous fistula surgery was performed on all patients. Their clinical data of hemoglobin (HB), albumin (ALB), cholesterol (CHOL), parathyroid hormone (PTH), blood glucose and blood pressure were collected before surgery, while the diameters of the radial artery and cephalic vein were measured by ultrasound. Results The operations in 742 patients were successful, but failed in 77 cases (accounting for 7.07%). The failure group was significantly older (61.3 ± 13.4 years) than the successful group (45.6 ± 11.2 years). The ratio of diabetes 36 (46.8%) and hypertension 20 (26.0%) was significantly higher in the failure group than in the successful group, respectively 235 (31.7%) and 145 (19.5%). The patients with blood pressure below 120/70 mm Hg had a higher risk of failed surgery (36.4%) than those with blood pressure above 120/70 mm Hg (9.16%). The cephalic vein and radial artery diameters were significantly smaller in the failure group (1.35 ± 0.64 mm, 2.13 ± 0.81 mm) than in the successful group (1.98 ± 0.47 mm, 2.47 ± 0.74 mm); the PTH levels in the failure group were significantly higher (782.39 ± 423.85) than in the successful group (378.83 ± 352.21). Conclusions The autogenous arteriovenous fistula surgery failure highly correlated with the patient's age, blood pressure, the primary disease and the vessel diameter. In addition, the PTH levels had a certain correlation with the failure of the fistula surgery.

In this article, a compact ultrawideband microstrip bandpass filter with triple narrow notched bands and wide stopband is proposed utilizing interdigital coupled-line and three quarter-wavelength resonator (QWR) coupling short stubs loaded in the 50-Ω feedlines. The short stubs can improve the passband performance and create new transmission zeros in the upper-stopband. The coupling QWR is studied and used to generate the desired notched band and deepen the stopband. By simply adjusting the dimensions of the QWRs, the center frequencies of the notched bands can be allocated at 3.6, 5.2, and 5.8 GHz, respectively. Good insertion/return losses and wide stopband are achieved as demonstrated in both simulation and experiment. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2874–2876, 2013

This paper presents a 35 GHz patch microstrip antenna array on an organic LCP (Liquid Crystal Polymer) substrate. To achieve a higher gain and narrower 3 dB beamwidth, a 4×4 antenna array has been designed and simulated using a 2×2 antenna array as unit array. The results show that an 18.9 dBi of gain and a 3 dB beamwidth of 20.7degrees.

A new concept called the dynamic coarse model is proposed and is applied to the optimization design of low-temperature co-fired ceramic (LTCC) multilayer RF circuits with the aggressive space mapping (ASM) technique. The dynamic coarse model is a combination of an evolutionary equivalent-circuit model and an efficient quasi-static numerical electromagnetic (EM) model-partial-element equivalent-circuit model. Namely, there are two forms of coarse models jointly in use: the coarse schematic model and the coarse EM model. The coarse schematic model evolutionarily incorporates parasitic effects that can be extracted from its accompanying coarse EM model. This process can greatly facilitate the original ASM process by easily determining a "high-quality" optimized coarse model. Two LTCC frequency-selective passive modules, i.e., a bandpass filter and a diplexer, are designed using the proposed scheme and ASM. No nonuniqueness in parameter extraction is encountered. Good convergence performance is achieved for the designs of both modules.

The aggressive space mapping (ASM) algorithm is applied to the optimization design of LTCC filters. The partial element equivalent circuit (PEEC) method is utilized as a coarse model. Low-pass and band-pass LTCC filters are designed with HFSS and IE3D adopted as the fine models, respectively. Conductor thickness is taken into account, since it is fairly large with respect to dielectric height. Only a few instances of fine-model simulation are needed. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 24–28, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20034

In this letter, a compact and high selectivity triple-band dual-mode microstrip bandpass filter (BPF) is proposed using two short-circuited stub-loaded stepped-impedance resonators (SIRs), which are same type but different size, that is, the SIR I and the SIR II with smaller size. The SIR I is designed to operate at the first and third passbands and the SIR II at the second passband. The passband frequencies can be conveniently tuned to desired values. Because of the intrinsic characteristics of the SIRs and the source–load coupling, six transmission zeros can be created to improve the selectivity of the triple-band BPF. Finally, a filter prototype located at 1.57 (GPS application), 2.4, and 5.2 GHz (WLAN application) is designed, fabricated, and measured. The simulated and measured results are presented and an excellent agreement is obtained. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:719–721, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26654