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Subway stations are important components of subway system planning and urban rail transit where passengers can board, alight, transfer, or wait. With an increase in urban passenger flow, subway stations must meet greater transfer‐space demands commensurate with growing station structure sizes. In this study, the field‐monitoring and analysis method was adopted to investigate the Huaxing Street Station of the Chengdu Metro Line 19 project and explore the temperature‐variation rule in the process of mass‐concrete pouring in the station floor. Based on an ABAQUS large‐finite‐element calculation programme and secondary development of damage and failure research methods, a mechanical model of mass‐concrete pouring in subway‐station floor construction was established. The pouring temperature effect, damage, and failure mechanism of mass‐concrete pouring in subway stations were comprehensively studied. The main results were as follows: (1) the maximum temperature difference between the upper and middle layers of the floor was dominant and reached a peak within 1–3 d after the completion of pouring, and the temperature difference gradually decreased with a decrease in the hydration‐heat reaction. (2) At 0–10 d, the damage ratio of the floor increased by 1.8%, predominantly in the form of longitudinal damage. Within 10–30 d, the damage and failure ratio of the floor increased by 1.86%, primarily in the form of transverse damage and failure. Within 30–40 d, the temperature of the floor stabilized and gradually approached the ambient temperature. The damage and failure ratio of the floor increased by 0.32% at this time. (3) The lower the ambient temperature, the greater was the damage sustained by the floor at different ages, and the ambient temperature had a significant influence on floor damage. [ABSTRACT FROM AUTHOR]

Super bacterial infection caused by metallo‐β‐lactamases (MβLs) has posed a serious public health threat, while developing inhibitors of MβLs is an ideal strategy to combat drug‐resistance. Here, seventeen sulfonylureas were synthesized and confirmed. Biological assay shown that these molecules effectively inhibited MβL ImiS, with an IC50 value in the range of 29.5–188.2 μM, and the best inhibitor competitively and irreversibly inhibited ImiS with a Ki value of 15.2 μM. Structure‐activity relationship analysis revealed that the chlorine‐substituted phenyl significantly raised inhibitory activity of sulfonylureas on ImiS. Antibacterial and chessboard dilution assays shown that the most sulfonylureas tested enhanced antimicrobial effect of meropenem (MER) on E. coli‐ImiS, and the two inhibitors with best effect resulted in an 8‐fold reduction in MIC of MER. Mice tests shown that the best inhibitor synergizing MER virtually diminished the load of E. coli‐ImiS in spleen and liver. Docking study revealed that the sulfonylurea reacts with ImiS mainly through the sulfonyl group, in which one of oxygen atoms coordinates to Zn(II), and forms two hydrogen bonds with Lys224 (2.1 Å) and His263 (3.1 Å). This work revealed the sulfonylureas are promising candidates for the development of ImiS inhibitors. [ABSTRACT FROM AUTHOR]

Osteoblasts play an important role in the regulation of bone homeostasis throughout life. Thus, the damage of osteoblasts can lead to serious skeletal diseases, highlighting the urgent need for novel pharmacological targets. This study introduces chemical genetics strategy by using small molecule forskolin (FSK) as a probe to explore the druggable targets for osteoporosis. Here, this work reveals that transglutaminase 2 (TGM2) served as a major cellular target of FSK to obviously induce osteoblast differentiation. Then, this work identifies a previously undisclosed allosteric site in the catalytic core of TGM2. In particular, FSK formed multiple hydrogen bonds in a saddle‐like domain to induce an "open" conformation of the β‐sandwich domain in TGM2, thereby promoting the substrate protein crosslinks by incorporating polyamine. Furthermore, this work finds that TGM2 interacted with several mitochondrial homeostasis‐associated proteins to improve mitochondrial dynamics and ATP production for osteoblast differentiation. Finally, this work observes that FSK effectively ameliorated osteoporosis in the ovariectomy mice model. Taken together, these findings show a previously undescribed pharmacological allosteric site on TGM2 for osteoporosis treatment, and also provide an available chemical tool for interrogating TGM2 biology and developing bone anabolic agent. [ABSTRACT FROM AUTHOR]

Digital geological survey methods have become supplementary approaches for traditional geological survey in the last two decades. In this paper, the Unmanned Aerial Vehicle (UAV)‐based photogrammetry technology is used to obtain the 3D point cloud model of rock outcrops. The clustering algorithm is used to automatically identify the rock discontinuity parameters. However, the obtained 3D point cloud model with high resolution often has a huge point data which usually poses a great challenge to the computational efficiency of the automatic identification. In fact, too‐dense point cloud data may not be necessary for cases when the rock mass is relatively intact. The optimal point cloud resolution, which balances the accuracy and efficiency, depends on the degrees of fragmentation of the rock mass under investigation. For a model with the same resolution, large‐size discontinuities may have quite a few redundant point cloud data that are of little use to improve the identification accuracy whereas small‐size discontinuities may not be properly identified due to insufficient number of data points. In this paper, the influence of the degree of fragmentation of rock mass on the identified results was investigated. The uniform grid method was adopted to sparse the 3D point cloud model. The optimal point cloud resolution for different discontinuities was suggested. The applicability and feasibility of the proposed approach were verified via three illustrative examples of typical rock slopes. [ABSTRACT FROM AUTHOR]

BACKGROUND Sacha inchi (Plukenetia volubilis L.) tea has been used as an adjuvant treatment for diabetes in Pu'er, in the Yunnan province of China. The effects of sacha inchi tea on diabetes and the underlying mechanisms remain unknown. This study was conducted to investigate the influence of a water extract of sacha inchi (P. volubilis L.) leaves (PWE) on hypoglycemic activity and gut microbiota composition in mice with streptozotocin (STZ)‐induced type 1 diabetes mellitus (T1DM). During the 6 weeks of the study, T1DM mice were administered PWE intragastrically at 400 mg kg−1 body weight (BW) per day. RESULTS: Treatment with PWE reduced excessive loss of BW and excessive intake of food. It significantly decreased blood glucose levels and improved oral glucose tolerance. The treatment caused protective histopathological transformations in sections of the pancreas, leading to decreased insulin resistance and improved insulin sensitivity. Treatment with PWE also significantly ameliorated disorders of the gut microbiota structure and increased the richness and diversity of intestinal microbial species in T1DM mice. At the genus level, the populations of several crucial bacteria, such as Akkermansia, Parabacteroides, and Muribaculum increased in the PWE treatment group but the abundance of Ruminiclostridium and Oscillibacter decreased. CONCLUSIONS: Treatment with PWE can ameliorate hyperglycemic symptoms in STZ‐induced T1DM mice, and the anti‐diabetic effect of PWE was related to the amelioration of gut microbial structural disorder and the enrichment of functional bacteria. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Bacterial resistance caused by metallo‐β‐lactamases (MβLs) has become an emerging public health threat, and the development of MβLs inhibitor is an effective way to overcome the resistance. In this study, thirteen novel O‐aryloxycarbonyl hydroxamates were constructed and assayed against MβLs. The obtained molecules specifically inhibited imipenemase‐1 (IMP‐1) and New Delhi metallo‐β‐lactamase‐1, exhibiting an IC50 value in the range of 0.10–18.42 and 0.23–22.33 μM, respectively. The hydroxamate 5 was found to be the most potent inhibitor, with an IC50 of 0.1 and 0.23 μM using meropenem and cefazolin as substrates. ICP‐MS analysis showed that 5 did not coordinate to the Zn(II) ions at the active site of IMP‐1, while the rapid dilution, thermal shift and MALDI‐TOF assays revealed that the hydroxamate formed a covalent bond with the enzyme. Cytotoxicity assays indicated that the hydroxamates have low toxicity in MCF‐7 cells. This work provided a potent scaffold for the development of MβLs inhibitors. [ABSTRACT FROM AUTHOR]

Introduction: The development of pancreatic ductal adenocarcinoma (PDAC) is closely tied with the immune system. C-C motif chemokine ligands (CCL) were proved to lead to immune recruitment and training. Thus, we reckoned CCL2 to be the kernel of immune suppression in PDAC tissues. Methods: We compared normal pancreatic tissues with PDAC tissues according to The Cancer Genome Atlas (TCGA) and clinical samples. Flow cytometry was used to identify M-MDSCs. We further demonstrated immune suppression of M-MDSCs according to proliferation rates of CD8+ T cells/CD4+ T cells. Levels of reactive oxygen species (ROS) and Arginase were also tested by flow cytometry, enzyme-linked immunosorbent assay, and western blot analysis. We also analyzed the specific mechanisms by cluster analysis after CCL2 stimulating M-MDSCs. Results: We found that CCL2 highly increased in PDAC tissues. CCL2 is positively related to CD33 and CD14, markers of monocytic myeloid-derived suppressor cells (M-MDSCs). We have demonstrated that CCL2 recruited M-MDSCs into PDAC tissues both in vitro and in vivo. M-MDSCs recruitment is accompanied by sustained immune suppression. Furthermore, we have found that M-MDSCs impeded T cell proliferation and produced high levels of ROS and Arginase, which can be enhanced by CCL2. Mechanistically, CCL2 stimulated M-MDSCs led to a significant upregulation of genes, a large part of which accumulated in the mitogen-activated protein kinase signaling pathway. Treatment of aloesin, MAPK signaling inhibitor, relieved the associated immunosuppressive phenotype induced by CCL2. Conclusions: Our study indicates that PDAC cells produced CCL2, which promoted localized M-MDSC recruitment and immune suppression, thereby promoting tumor progression. [ABSTRACT FROM AUTHOR]

We investigated the regulation of Cl− secretion by adrenoceptors in polarized 16HBE14o‐ human bronchial epithelial cells. Treatment with the nonselective β adrenoceptor agonist isoprenaline stimulated an increase in short‐circuit current (ISC), which was inhibited by the β adrenoceptor blocker propranolol. Treatment with procaterol, an agonist specific for the β2 adrenoceptor subtype, stimulated a similar increase in ISC, which was inhibited by the β2 adrenoceptor antagonist ICI 118551. Inhibitors of cystic fibrosis transmembrane conductance regulator (CFTR) and calcium‐activated Cl− channel (CaCC), but not K+ channel blockers, were able to inhibit the increase in ISC. "Trimultaneous" recording of ISC and intracellular cyclic adenosine monophosphate (cAMP) and Ca2+ levels in 16HBE14o‐ epithelia confirmed that the ISC induced by isoprenaline or procaterol involved both cAMP and Ca2+ signaling. Our results demonstrate that β2 adrenoceptors regulate Cl− secretion in the human airway epithelium by activating apical CFTRs and CaCCs via cAMP‐dependent and intracellular Ca2+‐dependent mechanisms, respectively. [ABSTRACT FROM AUTHOR]

A harmonically driven bio-radar based on the technique of a multiport interferometer (six-port) technique is proposed and studied in order to improve the performance of vital signs monitoring. The feasibility of estimating cardiopulmonary parametric signatures by deploying a harmonic multiport interferometer radar is presented. This scheme is helpful to reduce the noise floor and the effects of undesirable parasitic harmonics of breathing and intermodulation. A theoretical analysis is developed to explain why a better heart-beat detection using the proposed harmonic six-port radar architecture can be achieved. The well-known null point problem usually encountered in such radar detections of heart-beating signs is alleviated by the insertion of a fixed 45° phase shift between the two different frequencies in the six-port discriminator without an actual phase-shifter. Simulations are carried out to investigate detection accuracy and sensitivity issues for monitoring the vital signs by cancelling the breathing harmonics and intermodulation products. The concept is then validated by the measured results of an experimental prototype using the proposed harmonic six-port radar platform operating at 12 GHz (fundamental) and 24 GHz (harmonic). [ABSTRACT FROM AUTHOR]

Thru-reflect-line (TRL) calibration method were reviewed and the related kits based on substrate integrated waveguide (SIW) were re-examined, designed, and compared for measurements of SIW circuits. Different types of calibration kits were discussed and the design guidelines were provided. Filters working at 5 and 10 GHz were designed for the verification purpose of these calibration kits. Meanwhile, the TRL calibration method based on uniform SIW-coaxial transitions was proposed, which shows improved measurement accuracy. [ABSTRACT FROM AUTHOR]

The increasing number of pathogens expressing metallo-β-lactamases (MBLs), and in this way achieving resistance to β-lactam antibiotics, is a significant threat to global public health. A promising strategy to treat such resistant pathogens is the co-administration of MBL inhibitors together with β-lactam antibiotics. However, an MBL inhibitor suitable for clinical use has not yet been identified. Verona integron-encoded metallo-β-lactamase 2 (VIM-2) is a widespread MBL with a broad substrate spectrum and hence is an interesting drug target for the treatment of β-lactam-resistant infections. In this study, three triazolylthioacetamides were tested as inhibitors of VIM-2. One of the tested compounds showed clear inhibition of VIM-2, with an IC50 of 20 µ M. The crystal structure of the inhibitor in complex with VIM-2 was obtained by DMSO-free co-crystallization and was solved at a resolution of 1.50 Å. To our knowledge, this is the first structure of a triazolylthioacetamide inhibitor in complex with an MBL. Analysis of the structure shows that the inhibitor binds to the two zinc ions in the active site of VIM-2 and revealed detailed information on the interactions involved. Furthermore, the crystal structure showed that binding of the inhibitor induced a conformational change of the conserved residue Trp87. [ABSTRACT FROM AUTHOR]

T-cell lymphoma invasion and metastasis 2 ( TIAM2) is a neuron-specific protein that has been found ectopically expressed in hepatocellular carcinoma ( HCC). Results from clinical specimens and cellular and animal models have shown that the short form of TIAM2 ( TIAM2S) functions as an oncogene in the tumorigenesis of liver cancer. However, the regulation of TIAM2S ectopic expression in HCC cells remains largely unknown. This study aimed to identify the mechanism underlying the ectopic expression of TIAM2S in liver cancer cells. In this report, we provide evidence illustrating that Sp1 binds directly to the GC box located in the TIAM2S core promoter. We further demonstrated that overexpression of Sp1 in Hepa RG cells promotes endogenous TIAM2S mRNA and protein expressions, and knockdown of Sp1 in 2 HCC cell lines, HepG2 and PLC/ PRF/5, led to a substantial reduction in TIAM2S mRNA and protein in these cells. Of 60 paired HCC samples, 70% showed a significant increase (from 1.1- to 3.6-fold) in Sp1 protein expression in the tumor cells. The elevated Sp1 expression was highly correlated with both TIAM2S mRNA and protein expressions in these samples. Together, these results illustrate that Sp1 positively controls TIAM2S transcription and that Sp1-mediated transcriptional activation is essential for TIAM2S ectopic expression in liver cancer cells. [ABSTRACT FROM AUTHOR]

As angiogenesis is an important target for antitumour drugs, the agents that inhibit angiogenesis may help reduce the use of chemotherapy by blocking tumour blood supply. In this study, we investigated a potent angiogenesis inhibitor, ASC, a steroidal saponin compound, which has been purified from Ophitopogin japonicus (L.f) Ker.-Gawl. Our observations showed that ASC significantly suppressed human umbilical vein endothelial cell ( HUVECs) growth both in vitro and in vivo. This may be resulted from the G2/M cell cycle arrest effects of ASC. Moreover, ASC inhibited HUVECs invasion and tube formation processes, which were associated with endothelial cells remodelling. A mechanism study indicated that ASC down-regulated the expression of Src tyrosine kinase, further leading to the blockage of Akt-dependent matrix metalloproteinases (mainly for MMP-9) signalling pathway, which was functionally associated with angiogenic blood vessels. Finally, ASC significantly inhibited angiogenesis and MMPs/ VEGF expression in the subcutaneously injected matrigel in C57/BL mice. These findings suggest that ASC might be a potential drug candidate in anti-angiogenesis and anticancer therapies. [ABSTRACT FROM AUTHOR]

This study presents a compact circularly polarised array using tapered slot antenna fed by a substrate integrated waveguide (SIW) power divider. With the proposed topology, broadband circularly polarised property is achieved and total gain can be increased by controlling the element length, conserving the same footprint area. The different 2 × 2 cell configurations are investigated. Simple and integrated series-parallel SIW feed for the choose cell is presented. A 2 × 2 antenna array is designed and fabricated using SIW E-plane power divider. The measured 10 dB return loss and 3 dB axial ratio bandwidths are 35.65 and 32.3%, respectively. The measured antenna gain is 14.4 dBi at 35 GHz. [ABSTRACT FROM AUTHOR]

In this work, one-dimensional (1D) and 2D scan phased array antennas for 60 GHz radio communication and radar sensing systems are proposed, studied and experimentally validated in the substrate-integrated waveguide technology. A linearly polarised phased array with 1D scanned beams in the first part of this study and a right-hand circularly polarised (CP) array with 2D scanned beams in the second part are presented and discussed in detail. In the demonstrated 1D phased array, dielectric rod antenna is used as radiating elements to form 1 × 4 linear array and then a planar Butler matrix is integrated along with the array to obtain phase-steered beams. In the 2D phased array, CP radiating elements are used to form 2 × 4 array and then a folded Butler matrix is used to feed the CP array. Simulated and measured characteristics of these two phased array antenna radiation parameters are compared. The proposed phased arrays can be integrated into 60 GHz and other millimetre-wave radar and radio systems as an integrated antenna front-end. [ABSTRACT FROM AUTHOR]

K-band low-noise amplifier (LNA) chips are integrated in low-permittivity coplanar waveguide (CPW) and microstrip (MS) structures and are interconnected with substrate integrated waveguide (SIW) ports for direct applications in hybrid SIW technology. A commercial Hittite LNA chip is employed, and special transitions provide the interface between CPW or MS and SIW. The LNA with SIW-to-CPW transitions achieves more than 20 dB gain between 18 and 26.5 GHz, and input/output return losses remain below 10 dB between 21.5 and 26.5 GHz. Related design values for the LNA integration within SIW-to- MS transitions are: the gain is greater than 21 dB; the input/output return loss is better than 12 dB over the entire frequency range. Measurements of a back-to-back SIW-to-CPW transition are provided to put these values in perspective. The maximum noise figures are measured to be better than 4.6 and 4.2 dB, respectively, between 18 and 26.5 GHz. A comparison with measurements performed with an evaluation board supplied by the LNA manufacturer demonstrates successful K-band LNA chip integrations within CPW/MS and SIW. [ABSTRACT FROM AUTHOR]

The historical development and current state-of-the-art of various joint wireless communication and radar sensing systems are reviewed and discussed in this study. Different kinds of systems are categorised according to their modulation waveforms and duplex schemes. Pros and cons of each category are highlighted. To showcase the current research advances, several demonstration systems are introduced with emphasis on proposed research contributions in this emerging area, and their performances are compared with respect to both communication and radar modes. Also, a number of challenges are identified for the near future system developments and applications. [ABSTRACT FROM AUTHOR]

A millimeter-wave six-port implementation using combined substrate-integrated waveguide (SIW) and microstrip technologies, and low-loss short transition between microstrip and SIW is presented. The six-port is implemented using SIW hybrid couplers with continuous metalized grooves and Wilkinson power dividers. The proposed circuit is suitable for 77-GHz radar sensor front ends. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2488–2493, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25538 [ABSTRACT FROM AUTHOR]

Cheng C, Lu X, Wang G, Zheng L, Shu X, Zhu S, Liu K, Wu K, Tong Q. Expression of SATB1 and heparanase in gastric cancer and its relationship to clinicopathologic features. APMIS 2010; 118: 855-63. The purpose of this study was to investigate the expression of special AT-rich binding protein 1 (SATB1) and heparanase in human gastric cancer as well as its relationship to the clinicopathologic factors. Specimens from 102 patients who underwent radical gastrectomy between 2000 and 2002 were studied by immunohistochemistry for SATB1 and heparanase expression. SATB1 and heparanase were positively expressed in 48.0% and 51.0% of gastric cancer cases, respectively. The expression of SATB1 and heparanase was significantly correlated with the depth of invasion, tumor-node-metastatsis (TNM) stage, lymph node metastasis, whereas SATB1 expression was also significantly correlated with distant metastasis. Patients with SATB1-negative expression and heparanase-negative expression had higher survival rates than those with SATB1-positive or heparanase-positive expression. Moreover, a positive correlation was found between SATB1 and heparanase. In multivariable analysis, SATB1 expression was also identified as an independent prognostic indicator for gastric cancer. Our results suggest that combined analysis of SATB1 and heparanase expression may have significant value in determining invasion and metastasis of gastric cancer and assessing prognosis in patients with gastric cancer. [ABSTRACT FROM AUTHOR]

In this paper, a multi-region domain decomposition finite-difference time-domain (DD-FDTD) algorithm is proposed and developed for the analysis of multiple-objects electromagnetic (EM) problems. A significant number of mesh nodes between objects are removed since only local meshes are generated for each object. All the separated sub-domains are interconnected by the use of a 3-D time-domain Green's function. The coupling between objects can be regarded as the equivalent spherical wave irradiations. Incident signals of the equivalent spherical waves are expressed as a spherical wave input field array according to the Huygens principle. The near-field to far-field transformation is introduced to obtain the equivalent spherical wave. Moreover, the alternating direction implicit FDTD (ADI-FDTD) scheme is applied to overcome the limit of the stability condition and increase the speed of the simulation. The new algorithm has been demonstrated and applied to solve typical 3-D multi-objects EM scattering problems. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this article, the potential feasibility of integrating BST films into Si wafer by adopting tunable interdigital capacitor (IDC) with TiO2 thin film buffer layer is suggested. TiO2 as buffer layer is grown onto Si substrate by atomic layer deposition and the coplanar IDC on BaxSr1-xTiO3(500 nm)/TiO2(50 nm)/high resistivity Si (HR-Si) is fabricated. BST interdigital tunable capacitors integrated on HR-Si substrate with high tunability and low loss tangent are characterized for their microwave performances. BST/HR-Si and BST/TiO2/HR-Si IDCs show much enhanced tunability values of 31% and 40%, respectively as compared to the value of 21% obtained with BST film on MgO single crystal substrate at the bias of 5 kV/cm. BST/TiO2/HR-Si structure shows much improved figure of merit of 504.4 as compared to 418.53 and 101.68 of BST/MgO and BST/HR-Si structure, respectively. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2144–2148, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22657 [ABSTRACT FROM AUTHOR]

This paper reports a circularly polarized cross-slot coupled elliptical patch antenna for implementation in a new radio-frequency identification and localization system currently under development. The radio-frequency localization system in this work is composed of a reader and a semiactive tag (a battery feeds the tag to increase its reading range but the backscattering modulation principle is used to decrease its power consumption). The overall system is designed in the ISM frequency band of 5.8 GHz. This frequency band is a good compromise that permits a large bandwidth and a good range for use in a local positioning system (∼10 m). This antenna is to be used by the reader as its radiation pattern is semispherical. It provides the circular polarization required by the targeted application to allow the tag identification within any physical position. The antenna bandwidth and axial ratio were enhanced using a proper design and a cross-slot feeding of the patch. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 336–339, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22136 [ABSTRACT FROM AUTHOR]

An experimental receiver prototype operating over the S-, C-, and X-bands, based on a MHMIC multiport, is designed, fabricated, and measured. Comparative simulation and measurement results for 8PSK modulated signals are presented and discussed. The RF input power sweep and the DC offset of the proposed multiport demodulator are particularly analyzed. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 817–822, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21484 [ABSTRACT FROM AUTHOR]

An H-plane hybrid ring 3-dB power divider constructed with substrate integrated rectangular waveguide (SIRW) is proposed. Theoretical simulations are carried out at the X- and Ka-bands. The results show that the isolation between two output ports is high up to 35 dB and good 3-dB power division within the band of interest is observed also, that is, less than 0.3-dB derivation in the band of interest. In addition, the simulation results at the X-band shows a bandwidth of 10% at -15 dB. A prototype in the Ka-band is fabricated and the measured data at the Ka-band shows a bandwidth of 7% at -15 dB, in good agreement with simulation. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 502–505, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21392 [ABSTRACT FROM AUTHOR]

In-line ports are usually used to feed substrate integrated waveguide (SIW) resonator in an in-line transmission circuit. However, the higher order mode TE102 is excited as well as the fundamental mode TE101 thereby deteriorating the selectivity. Here the authors present a method to remove the selectivity deterioration. By additionally introducing TE201, the TE102 and the TE201 can be counteracted with each other by taking advantage of their out-phase out-coupling, and then both modes are suppressed well in a SIW resonator feeding with in-line ports. Two prototypes based on square and rectangle cavity are fabricated, respectively and measured to verify the proposed technique. The results agree with the expectation well. It shows the potential to be implemented in the in-line transmission circuit with SIW resonator. [ABSTRACT FROM AUTHOR]

Protein tyrosine phosphatase 1B (PTP1B) acts as a physiological negative regulator of insulin signaling by dephosphorylating the activated insulin receptor (IR). Here we examine the role of PTP1B in the insulin-sensitizing action of rosiglitazone (RSG) in skeletal muscle and liver.Fat-fed, streptozotocin-treated rats (10-week-old), an animal model of type II diabetes, and age-matched, nondiabetic controls were treated with RSG (10 μmol kg−1 day−1) for 2 weeks.After RSG treatment, the diabetic rats showed a significant decrease in blood glucose and improved insulin sensitivity. Diabetic rats showed significantly increased levels and activities of PTP1B in the skeletal muscle (1.6- and 2-fold, respectively) and liver (1.7- and 1.8-fold, respectively), thus diminishing insulin signaling in the target tissues.We found that the decreases in insulin-stimulated glucose uptake (55%), tyrosine phosphorylation of IRβ-subunits (48%), and IR substrate-1 (IRS-1) (39%) in muscles of diabetic rats were normalized after RSG treatment. These effects were associated with 34 and 30% decreases in increased PTP1B levels and activities, respectively, in skeletal muscles of diabetic rats. In contrast, RSG did not affect the increased PTP1B levels and activities or the already reduced insulin-stimulated glycogen synthesis and tyrosine phosphorylation of IRβ-subunits and IRS-2 in livers of diabetic rats.RSG treatment in normal rats did not significantly change PTP1B activities and levels or protein levels of IRβ, IRS-1, and -2 in diabetic rats.These data suggest that RSG enhances insulin activity in skeletal muscle of diabetic rats possibly by ameliorating abnormal levels and activities of PTP1B.British Journal of Pharmacology (2005) 146, 234–243. doi:10.1038/sj.bjp.0706306; published online 4 July 2005 [ABSTRACT FROM AUTHOR]

A nonradiative dielectric waveguide (NRD) embedded in a metamaterial with negative permittivity or permeability is proposed and theoretically characterized in this work. This dielectric waveguide structure is inherently nonradiating at bends and discontinuities, since metamaterials with negative permittivity or permeability cannot support any propagating modes. The waveguide supports hybrid longitudinal section magnetic (LSM) and longitudinal section electric (LSE) modes. It is demonstrated that the LSM11 mode is the lowest-order mode when the waveguide dimensions are properly designed. The theoretical results indicate that this guided-wave structure is able to narrowly confine electromagnetic fields within the core dielectric strip, thus exhibiting nonradiating properties. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 207–210, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20771 [ABSTRACT FROM AUTHOR]

A hybrid scheme called finite element method of lines is proposed and described for modelling and analysis of generalized computational electromagnetic problems with emphasis on a number of irregular waveguide examples. This new technique is developed by combining a finite element method with a method of lines so that it can handle not only irregular composite geometry but also maintain high accuracy enjoyed by semi-analytical procedures. Analytical and numerical algorithmic building blocks of this new scheme are discussed in detail such as geometry discretization, element mapping, element trial functions, reformulation and computational issues of non-linear ordinary differential equations. Our results show that this new technique is able to efficiently solve complex problems as compared with the conventional method of lines. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, the application of the edge-based vector finite-element method combined with the short-open calibration (SOC) technique to three-dimensional waveguide discontinuity was presented. This SOC technique is directly accommodated in the FEM algorithm, and is used to truncate the computational domain. The developed FEM algorithm is applied to the modeling of dielectric-filled waveguide discontinuities that can be segmented into two distinct sections: the static model of feed lines, and the dynamic model of circuit discontinuity. The FEM is formulated in such a way that the port voltages and currents are explicitly represented through relevant network matrices. The SOC technique is used to remove or separate unwanted parasitics brought by the approximation of the impressed voltage source, as well as the problem of the resulting consistency between different simulations. Truncation of the computational domain by the SOC technique makes the iterative solvers for large sparse linear matrix equations from the FEM converge much faster than by perfectly matched layers (PML). Results for full-height/partially dielectric-filled waveguide discontinuities are very well compared with available publications. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 27: 438–444, 2000. [ABSTRACT FROM AUTHOR]

A generalized method of lines algorithm is presented for characterizing unbounded and bounded circuits. Finite substrate extent and inhomogeneous dielectric layers are rigorously considered in this field-based model. Radiating properties of unbounded regular and irregular microstrip patch resonators and arrays are studied with emphasis on effects of mutual coupling and finite dielectric extent on complex resonant frequencies. In addition, unbounded loss effects for microstrip open-end and 90° angular bend deposited on finite substrate as well as chip-to-chip discontinuities are also investigated. Our developed algorithm incorporates an absorbing boundary condition using the Padé approximation to simulate any potential radiation and leakage losses for resonator structures while an improved lossy absorbing boundary condition (LABC) that can handle both propagating and evanescent waves is used to determine the unbounded effects for waveguiding structures. Results indicate interesting properties of the finite extent of dielectric substrate on resonance and radiation characteristics, and also on unbounded radiation and leakage losses. Copyright © 2000 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A comprehensive analysis procedure is presented to investigate mode propagation in a class of semiconductor- based transmission lines suitable for application in microwave or opto-electronic circuits. The method of lines (MoL) has been used to investigate single or multiconductor planar transmission line structures printed on a combination of insulating and semiconducting substrate. Homogeneous as well as inhomogeneous doping areas in the semiconductor are included in the theoretical formulation. Numerical results are presented for 111-V semiconductor travelling wave electro-optic modulators in double-rib, multi-layer strip waveguide configuration, rnicroslab™ transmission lines with partial and full strip cover and slow-wave MIS microstrip/ coplanar transmission lines on thick and thin film semiconductor substrate with gradually inhomogeneous doping layer. [ABSTRACT FROM AUTHOR]

This paper presents a class of waveguide bandpass filters with conformal iris patterns made of planar circuits suitable for integration of active devices. Multiple planar inserts are located along the propagation path with specially designated spacing between two adjacent planar inserts on which the iris patterns are etched. The electrical performance of such novel filters with the enclosure of a circular waveguide is demonstrated by the field-theoretical design and experimental characterization of a three-pole Tschebyscheff-type filter. Results of this type of planar-insert-based waveguide filter is compared with its conventional all-metallic iris counterpart designed at the same center frequency, showing nearly an identical frequency response between the two different topologies. © 1997 John Wiley & Sons, Inc. Microwave Opt Technol Lett 16: 77–80, 1997. [ABSTRACT FROM AUTHOR]

An efficient and accurate parameter extraction technique is proposed for characterizing complex microwave resonance problems. The transmission line matrix algorithm is used to simulate resonator structures of different geometries in the frequency domain. A sequence of sinusoidally modulated impulses with exponentially damped amplitude is introduced to account for the influence of power dissipation clue to ohmic and dielectric losses or loading effects, thereby extracting the Q-factor and resonant frequency without a Fourier transform. Theoretical results are compared with other solutions and experiments. [ABSTRACT FROM AUTHOR]

In this paper, a novel numerical technique to solve the electromagnetic boundary value problem is described. This FEMOL is developed by combining the finite-element method and the method of lines so that it not only has high flexibility to treat geometrically and compositionally complex problems, but also maintains high accuracy of the semianalytical technique. The geometry discretization, element mapping, element trial function, and standard ordinary differential equation construction are discussed in detail. Our numerical result demonstrates that this method can successfully solve complex problems with fewer mesh lines when compared with the conventional method of lines. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 18: 264–268, 1998. [ABSTRACT FROM AUTHOR]

Substrate integrated waveguide (SIW) matching terminations or loads are proposed for low-cost integration in SIW circuits and systems. The principles of narrowband and broadband SIW terminations are demonstrated and discussed. Both narrowband and broadband terminations are optimised, fabricated and measured over the frequency range of 6–15 GHz. Relative frequency bandwidths (∣S11∣ < 20 dB) of the narrowband and broadband terminations are 7.6 and 42.6%, respectively. Good agreement between the measured and simulated results validates the feasibility of the proposed design strategies of SIW terminations. [ABSTRACT FROM AUTHOR]

This Letter proposes a balanced dual-mode substrate integrated waveguide (SIW) filter for the first time. Based on dual-mode square SIW cavities, perturbation vias, and balanced ports, the quasi-elliptic differential mode response with improved selectivity as well as highperformance common mode suppression can be obtained conveniently. Resonator number decrease and compact size can also be available. [ABSTRACT FROM AUTHOR]

A novel technique to design substrate integrated waveguide (SIW) resonator with harmonic suppression is proposed. The spurious band arising from the harmonics is designed as well as the fundamental passband. The bandwidth of the spurious band is designed to be zero to realise harmonic suppression. At the same time, the fundamental properties of the SIW are almost not affected, and no additional circuit area is required. The harmonic suppression and the fundamental passband can be designed independently of each other. An SIW resonator with harmonic suppression and an SIW filter with wide stopband are fabricated and measured to verify the proposed technique. The results agree with expectation well. [ABSTRACT FROM AUTHOR]

A novel dual-mode filter using circular high-order mode cavities based on substrate integrated waveguide technology is presented. Its dual-mode character and transmission responses are carefully investigated. Filters in both Ka- and Q-band using two congruent cavities in folded configuration are designed, fabricated with standard PCB process, and measured. Small insertion loss, flat group delay, and good tolerance are observed, which is consistent with the simulation. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1743–1745, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24456 [ABSTRACT FROM AUTHOR]

In this article, a transition of coplanar line to substrate-integrated waveguide onto electro-optical LiNbO3 substrate for the design of traveling-wave optical phase modulator at 60 GHz were proposed, designed, and fabricated for the first time. Micromachining of the LiNbO3 substrate, which is transparent to a wide range of laser wavelengths, was done by using Excimer laser. Metallized via holes around the coplanar line are considered for the purpose of mode suppression. Also, a cavity resonator was designed to increase the circuit bandwidth. Measurement results show about 5 GHz bandwidth for the demonstrated substrate-integrated electro-optical waveguide. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1105–1107, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24229 [ABSTRACT FROM AUTHOR]

A low-temperature co-fired ceramic (LTCC) X-band receiver front-end is designed using a novel embedded multilayer substrate integrated waveguide filter. The filter is a quasi-elliptic type, fabricated into multilayers on LTCC process, making it compact as well as of low cost and high selectivity. Simulated and experimental results of the filter and X-band receiver front-end are presented. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 285–287, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23057 [ABSTRACT FROM AUTHOR]

In this paper, error-control coding is used with a six-port direct-digital QPSK receiver [1] in an AWGN channel. The direct-conversion wideband six-port millimeter wave receiver proposed herein meets the needs of MMIC mass-market wireless communications. Convolutional code and Turbo code are used as the channel codes for the first time in this type of receiver. The BER results for the convolutional code, turbo code, and the uncoded system in the six-port receiver, are presented at a bit rate of 1 Mbps. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 465–467, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10791 [ABSTRACT FROM AUTHOR]