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Using phage display technology, 810A was developed as a novel peptide, which binds to the C-terminal domain of connective tissue growth factor (CTGF). The present study investigated whether this peptide could neutralize CTGF and block its biological activity as a specific strategy to treat pulmonary fibrosis in vitro and in vivo. Human bronchial epithelial (16HBE) cells were treated with CTGF to evaluate the anti-CTGF capability of 810A using MTT testing, cell migration assays, and Western blotting. The action of 810A in mouse models of bleomycin (BLM)-induced pulmonary fibrosis was evaluated according to leukocyte counts in bronchoalveolar lavage fluid (BALF), hydroxyproline content, and pathological analysis. Treatment with 810A resulted in inhibition of cell proliferation, migration, and increases in transforming growth factor-beta (TGF-β) and α-Smooth muscle actin (α-SMA) caused by CTGF treatment in vitro. In vivo, 810A significantly alleviated fibrosis in the pulmonary index. Inflammation was inhibited, as inferred by the reduced number of leukocytes in BALF. Pathophysiological analysis indicated that hydroxyproline content, alveolar enlargement, interstitial inflammatory infiltration, and collagen deposition were reduced. Collectively, these data suggest that 810A may potentially be a CTGF-specific, small-molecule antagonist, providing a new method for prevention and treatment of pulmonary fibrosis.

A series of Ce-Ti mixed oxides (CeaTi1−a) were successfully synthesized by a spontaneous deposition method and evaluated in selective catalytic reduction of NO with NH3 (NH3-SCR). The structures and properties of the CeaTi1−a catalysts were characterized by means of XRD, Raman, TEM, N2-sorption, XPS, H2-TPR and NH3-TPD. The results demonstrated that lots of Ce-O-Ti species were formed because of the strong synergistic interaction of gelation of TiO2 and deposition of Ce3+ during the preparation process of CeaTi1−a catalysts. As results, the CeaTi1−a catalysts exhibited excellent redox ability, enrichment of Ce3+ species, high surface adsorbed oxygen concentration, and abundant acid sites. The CeaTi1−a catalysts showed remarkable catalytic activity with broad operation temperature window, and Ce0.5Ti0.5 catalyst exhibited the best catalytic activity and extraordinary H2O/SO2 durability. The in-situ FTIR results revealed that the mechanisms of L-H and E-R existed synchronously during the NH3-SCR reaction, and the former one was predominant due to its rapid reaction rate.

A new substrate composing of Ag nanoflowers on graphene@Cu net (AgNFs/G@Cu) was fabricated on the flexible woven copper net. Graphene, an ideal 2D plane, provides better dispersion of regular electrodeposited AgNFs arrays. Graphene nanogap was used to enhance the EM coupling between AgNFs and metal Cu substrate. Regular AgNFs arrays offer denser “hotspots”, which further enhance the EM coupling. High sensitivity (rhodamine 6G (R6G): 10−14 M, crystal violet (CV): 10−12 M) and good homogeneity are realized in our experiment and proved by the COMSOL simulation. Cu net, remarkable flexibility and practicality, allows for a close contact to the sample surface by swabbing. Malachite green (MG) as low as 10−11 M on the surface of the marine fish can be detected. This work may offer novel and practical SERS applications in the areas of pesticide residue, food security and biotechnology.

Recently, biological materials have attracted more and more attentions on preparing the surface-enhanced Raman spectroscopy (SERS) substrate with the conspicuous SERS performance. Herein, we demonstrate a simply facile and inexpensive approach to fabricate a novel natural SERS substrate based on graphene oxide-Ag nanoparticles-Mytilus coruscus (GO-AgNPs-M.c.). The surface-enhanced resonance Raman spectroscopy (SERRS) signals of the Rhodamine 6G (R6G) on the GO-AgNPs-M.c. hybrids exhibit the much better SERRS performances in terms of the sensitivity, the signal reproducibility and the antioxidant stability than that on the AgNPs-M.c. one. The well electric field enhancement contribution is likewise confirmed in theory via the COMSOL software. Moreover, the successful detection of trace malachite green (MG) and methylene blue (MB) indicates the well feasibility for multi-molecules detection on the GO-AgNPs-M.c. hybrids. Thus, this inexpensive and high-efficiency natural SERS substrate have great potential for the considerable biochemical SERS applications and broaden the way for preparing multiple SERS platforms derived from other natural materials.

For application in practice, reducing the cost and simplifying the steps in fabrication of SERS substrates with excellent property are still the important factors. Here, a three-dimensional (3D) Ag nanoparticles (NPs) obtained by facile thermal evaporation is obtained for SERS. The Raman enhancement effect gradually become strong as the number of Ag NPs layers increase and attain the best until four layers Ag NPs deposited for the finite penetration depth of incident laser. The intensity of Raman signal collected from the four-layer Ag NPs substrate is around 11.3 times stronger than that from one-layer Ag NPs. Besides, the reproducibility of the SERS substrate was also significantly promoted as the layers of Ag NPs increases. The SERS substrate exhibits temporal stability and its enhancement factor attains 6.8 × 108. Furthermore, the SERS substrate can easily combine with some other blocks with superior SERS property and show better SERS ability. Additionally, the in-situ trace analyses in aquatic products were realized by flexible Ag NPs/PET substrate.

The three-dimensional (3D) MoS 2 decorated with Au nanoparticles (Au NPs) hybrids (3D MoS 2 -Au NPs) for surface-enhanced Raman scattering (SERS) sensing was demonstrated in this paper. SEM, Raman spectroscopy, TEM, SAED, EDX and XRD were performed to characterize 3D MoS 2 -Au NPs hybrids. Rhodamine 6G (R6G), fluorescein and gallic acid molecules were used as the probe for the SERS detection of the 3D MoS 2 -Au NPs hybrids. In addition, we modeled the enhancement of the electric field of MoS 2 -Au NPs hybrids using Finite-difference time-domain (FDTD) analysis, which can further give assistance to the mechanism understanding of the SERS activity.

The magnetic field integral equation (MFIE) is widely used in the analysis of electromagnetic scattering problems for conducting objects. Usually, the MFIE is solved by the method of moments (MoM) using the Rao–Wilton–Glisson (RWG) basis functions. In this paper, a new kind of basis function which is named the piece-wise constant vector basis function is proposed and used to solve the MFIE by MoM. Definition of this kind of basis function is given. The calculation of the impedance matrix entries is presented in detail. This kind of basis function is then used for the solution of the MFIE for electromagnetic scattering problems. The radar cross section (RCS) results and the iterative property of both kinds of basis functions are presented. It is shown that the piece-wise constant vector basis functions give similar RCS results as those of the RWG basis functions. Particularly, when iterative solver is used to solve the resultant linear system, the solution scheme using the piece-wise constant vector basis functions iterates much faster than that using the RWG basis functions.

Passively Q-switched mode-locked dual-wavelength Nd:GYSGG laser using graphene oxide saturable absorber is demonstrated. The output spectrum peaked at 1057.28 nm and 1060.23 nm with wavelength spacing of 3 nm has been measured. At the pump power of 5 W, the maximum average output power of 0.189 W was obtained with the optical conversion efficiency of 3.79%. The mode-locked pulse inside the Q-switched envelope has a repetition rate of 100 MHz and its pulse width is estimated to be about 441 ps. In addition, a simple way to fabricate few layers graphene oxide saturable absorbers has been reported.

A homogeneous titanium oxide device is fabricated by Molecular Beam Epitaxy and the excellent memristive behavior could be observed. The resistance ratio between high resistance state and low resistance state increases as the thickness of titanium oxide or the oxygen content reduces. The forming voltage is lower than the previous report. Based on the experimental results, we suggest a double-interface conductive filament model and calculate the current–voltage curve of the device in agreement with experimental measurements. The result indicates that the forming voltage of the device will rise with increasing of the chemical potential differences across the two interfaces. In other words, the switching voltage could be adjusted by selecting a proper electrode and oxide materials.

We demonstrate the use of molybdenum disulfide (MoS2)-based saturable absorber to develop a passively Q-switched Nd:YVO4 laser. The few-layer MoS2 saturable absorber was prepared by mixing MoS2 with alcohol and then evaporating the mixture on a substrate. Using an MoS2 saturable absorber, stable Q-switching operation was achieved with a laser pulse width of 327 ns and a repetition rate of 5 kHz under a pump power of 2.23 W. Due to the simple manufacturing process and high saturated absorption characteristics, MoS2 seems to be a suitable material as a saturable absorber for solid-state lasers.

The structure of 1 × 2 type photonic crystal power splitter with ring resonators is designed in a two-dimension square-lattice dielectric-rod photonic crystal structure, and it consists of one input and two outputs. Its transmission performance is investigated by using the finite-difference time-domain (FDTD) method. The results show that the structure has high transmission efficiency in the third communication window (wavelength 1550 nm), can split pass band electromagnetic waves equally. It is compact with low loss and design flexibility in propagation direction of electromagnetic waves.

We present a novel method to solve the magnetic field integral equation (MFIE) using the method of moments (MoM) efficiently. This method employs a linear combination of the divergence-conforming Rao–Wilton–Glisson (RWG) function and the curl-conforming n × RWG function to test the MFIE in MoM. The discretization process and the relationship of this new testing function with the previously employed RWG and n × RWG testing functions are presented. Numerical results of radar cross section (RCS) data for objects with sharp edges and corners show that accuracy of the MFIE can be improved significantly through the use of the new testing functions. At the same time, only the commonly used RWG basis functions are needed for this method.

In this paper, we study the accuracy and the efficiency of the monopolar divergence-conforming Rao–Wilton–Glisson (RWG) and the monopolar curl-conforming n×RWG basis functions for the magnetic field integral equation (MFIE). Similar to cases using RWG and n×RWG basis functions for the MFIE, there are two impedance matrix elements calculation schemes if the monopolar RWG and monopolar n×RWG basis functions are used to the MFIE, respectively. The monopolar basis functions and the implementation schemes used for the MFIE are discussed. The scattering cross section data as well as the CPU time needed to fill the corresponding impedance matrix obtained from numerical solutions of these implementation schemes using monopolar basis functions are investigated. For the monopolar basis functions and the implementation schemes considered, the first scheme of the MFIE using the monopolar curl-conforming n×RWG basis functions gives most accurate results and it is the best choice for the use of the monopolar basis functions to the MFIE.

The magnetic field integral equation (MFIE) is widely used in method of moments (MoM) for electromagnetic scattering analysis of arbitrarily shaped three-dimensional conducting objects. Besides the well-known Rao–Wilton–Glisson (RWG) basis functions, the curl-conforming n×RWG basis functions are also used in MFIE to improve its accuracy. However, there are two different impedance matrix element formulations that result from the use of the n×RWG basis and testing functions to the MFIE in the literature. Moreover, one of the formulations is more complicated than the other. This stimulates us to explore which formulation is more efficient in improving the accuracy of the MFIE. This paper investigates the efficiency of two impedance matrix element formulations resulting from the use of the curl-conforming n×RWG basis and testing functions to the MFIE. Details to calculate the impedance matrix elements are studied. Numerical results show that the radar cross section (RCS) results of the first formulation are more accurate than those of the second one while consuming only about half of the time to fill the impedance matrix for the second formulation. Thus, compared with the second formulation, the first formulation resulting from the use of the curl-conforming n×RWG basis functions to the MFIE is a better choice for scattering analysis of three-dimensional conducting objects.

We present a novel implementation of the magnetic field integral equation (MFIE) with the use of the combined Rao–Wilton–Glisson (RWG) basis and testing functions. Implementation details are outlined in the context of the method of moments. For a wide variety of small sharp-edged objects, we show that accuracy of the MFIE can be greatly improved with a combination parameter of about 0.2 for the combined RWG functions. This is achieved with relatively coarse discretization for the scatterers and with only minor modifications in the existing codes based on the RWG and n×RWG functions.

Numerical character of a new magnetic field integral equation (MFIE) formulation solved by the method of moments (MoM) is studied. In this new formulation, monopolar Rao–Wilton–Glisson (RWG) functions are used as both the basis and the testing functions. Calculation details for the impedance matrix elements of this new formulation are presented with a form suitable for programming. Numerical results for electromagnetic scattering analysis of several small sharp-edged conducting objects show that the new formulation using the monopolar RWG basis functions is much more accurate than the traditional one using the RWG and the monopolar RWG basis functions.

Accurate calculation of the almost singular double surface integrals is essential for successful solutions of the magnetic field integral equation (MFIE) by method of moments (MoM) using Rao-Wilton-Glisson (RWG) basis functions, especially for the scattering analysis of small conducting objects. In this paper, an accurate singularity extraction technique to avoid logarithmic singularity of the integration on the testing triangles is used for the MFIE. The numerical examples of several small sharp-edged conducting objects demonstrate that accuracy of the MFIE is improved with the use of the new technique. In addition, the MFIE converges much faster than the electric field integral equation (EFIE) when iterative equation solvers are employed, which means high efficiency and a suitable choice for very low frequency small sharp-edged conducting object problems using this new singularity extraction technique.

The method of moments (MoM) solution on the magnetic field integral equation (MFIE) for electromagnetic scattering problems of conducting objects with Rao–Wilton–Glisson (RWG) basis functions requires the evaluation of almost singular double surface integrals over triangular subdomains. Calculating these integrals accurately is essential for the successful solution of the MFIE by MoM especially for small sharp-edged conducting objects. This paper studies the singularity of the MFIE and uses an accurate singularity extraction technique to avoid logarithmic singularity of the integration on the testing triangles for the MFIE. Based on the numerical examples of several small sharp-edged conducting objects, it is demonstrated that the accuracy of the MFIE is improved greatly with the use of the new singularity extraction technique.

A novel Smith–Purcell (SP) free-electron laser (FEL) with axial-symmetrical structure is proposed. The distribution of the high frequency field in the resonator is analyzed and the operating frequency and output power are also studied by the use of particle-in-cell (PIC) simulation method. Results indicate that coherent radiation with output peak power up to 58 MW at millimeter wavelengths can be generated by using relativistic electron beams of moderate energy.

The compact free electron maser (FEM), with the advantages of small size and low cost, is important for realistic applications in medicine and industry. In order to utilize the planar wiggler to the best advantage and simultaneously to reduce the necessary electron beam voltage and the size of FEM device, we propose to utilize an elliptical waveguide as the high frequency structure of planar wiggler FEM. A set of universal operating equations suitable for elliptical waveguide and rectangular waveguide FEMs is derived by using the nonlinear theory. The characteristics of the FEMs are numerically analyzed, comparatively.

OBJECTIVE: Our purpose was to investigate the spatiotemporal properties of the fetal magnetocardiogram. STUDY DESIGN: Fetal magnetocardiogram maps were measured for the first time in 20 subjects from 22 to 39 weeks' gestation. Waveform and topographic maps were used to display the data. RESULTS: The maps showed spatiotemporal properties consistent with simple volume conductor theory: topography was closely related to the presentation of the fetus, Q-wave sources were dipolar and localized, the magnetic heart vector rotated extensively during the QRS complex, and close correspondence was observed between fetal and neonatal maps. Ventricular depolarization and events in the cardiac cycle could be visualized in considerable detail by means of a time series of topographic maps. CONCLUSION: Fetal magnetocardiogram shows excellent spatiotemporal properties and is well suited for in utero studies of fetal heart activity. (AM J OBSTET GYNECOL 1994;170:770-6.)

Fetal heart rate variability was derived from fetal magnetocardiogram recordings in ten subjects at gestation ages 32–38 weeks. Maternal interference was negligible and R-wave detection was highly reliable. Oscillations suggestive of respiratory sinus arrhythmia (RSA) were prominent in many of the heart rate tracings. Spectral analysis was used to quantify heart rate variability and to examine the influence of the RSA-like oscillations on heart rate variability. The oscillations were associated with increased power in the frequency range 0.4–1.0 Hz (P ≤ 0.05). Magnetic recording appears to offer significant advantages for investigation of beat-to-beat fetal heart rate throughout the latter stages of pregnancy.