Search

Organomineral associations in micro-aggregate architecture are important in soil functions. The effect of greenhouse management on micro-aggregation should be investigated to rationally maximize the benefits of solar greenhouses. The relationships between combined organic matter and inorganic minerals were studied during a long-term greenhouse experiment for 15 years in Shenyang, China. Stepwise settlement method was used to isolate micro-aggregate fractions. Combined organic matter, sesquioxides and combined inorganic phosphorus were also determined. The mass proportions of 50–250 and <1 μm size fractions decreased under long-term greenhouse management. The opposite trends were observed in 10–50 and 1–5 μm size fractions. Significant correlations were also determined between the combined organic matter and amorphous Al oxide, complex Fe and Al oxides, and phosphorus combined with Ca and occluded phosphorus. These results indicated that greenhouse management significantly affected the turnover of organomineral associations in micro-aggregates. [ABSTRACT FROM AUTHOR]

Aim: To test the diagnostic performance of a deep learning-based system for the detection of clinically significant pulmonary nodules/masses on chest radiographs.Materials and Methods: Using a retrospective study of 100 patients (47 with clinically significant pulmonary nodules/masses and 53 control subjects without pulmonary nodules), two radiologists verified clinically significantly pulmonary nodules/masses according to chest computed tomography (CT) findings. A computer-aided diagnosis (CAD) software using a deep-learning approach was used to detect pulmonary nodules/masses to determine the diagnostic performance in four algorithms (heat map, abnormal probability, nodule probability, and mass probability).Results: A total of 100 cases were included in the analysis. Among the four algorithms, mass algorithm could achieve a 76.6% sensitivity (36/47, 11 false negative) and 88.68% specificity (47/53, six false-positive) in the detection of pulmonary nodules/masses at the optimal probability score cut-off of 0.2884. Compared to the other three algorithms, mass probability algorithm had best predictive ability for pulmonary nodule/mass detection at the optimal probability score cut-off of 0.2884 (AUCMass: 0.916 versus AUCHeat map: 0.682, p<0.001; AUCMass: 0.916 versus AUCAbnormal: 0.810, p=0.002; AUCMass: 0.916 versus AUCNodule: 0.813, p=0.014).Conclusion: In conclusion, the deep-learning based computer-aided diagnosis system will likely play a vital role in the early detection and diagnosis of pulmonary nodules/masses on chest radiographs. In future applications, these algorithms could support triage workflow via double reading to improve sensitivity and specificity during the diagnostic process. [ABSTRACT FROM AUTHOR]

The purpose of this study is to find the optimal designing parameters of a plate-fin heat sink under natural convection using the Particle Swarm Optimization (PSO) Algorithm. Minimization of entropy generation rate under given space restrictions is considered as objective functions. All relevant design parameters for plate-fin heat sinks are the fin height, fin number, fin thickness. The constraints of the variables are set according to the suggestion structure design. And this three variables influence on entropy generation are presented. In the present study, In order to prevent the size of the heat sink is too large, we use the penalty function method in this study. Then the code for the PSO is written in MATLAB. On this basis, the optimal size of heat sink was obtained through the particle swarm algorithm for numerical simulation of this model: fin height is 44.8mm, number of fins is 25, fin thickness is 0.6mm and base temperature is 342.6241k. [ABSTRACT FROM AUTHOR]

Abstract: Nd-doped Si-rich silicon oxide thin films were produced by radio frequency magnetron co-sputtering of three confocal cathodes: Si, SiO2, and Nd2O3, in pure argon plasma at 500°C. The microstructure and optical properties of the films were investigated versus silicon excess and post-deposition annealing treatment by means of ellipsometry and Fourier transform infrared spectrometry as well as by the photoluminescence method. A notable emission from Nd3+ ions was obtained for the as-deposited sample, while the films annealed at 900°C showed the highest peak intensity. The maximum emission was observed for the films with 4.7at% of Si excess. [Copyright &y& Elsevier]

A novel design of dual circularly polarized antenna for application in Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access (WiMAX) is pro-posed in this paper. This antenna characterizes a small size and exact circularly polarized (CP) bandwidths for practical application. A new interdigitated structure is put forward to realize dual-band circular polarization, which is made up of a T-shaped strip and a quasi L-shaped strip. The coupling of the two branches of the strips makes it get two circularly polarized bands, and an L-shaped slot is used to enhance the polarization effect. The mea-sured results show that the impedance bandwidth is approximately 34.4% (2.65-3.75 GHz) for the lower band and 26.5% (4.9-6.4 GHz) for the upper band, and the 3 dB axial ratio bandwidth is successfully covering the WiMAX (3.3-3.6GHz) and the HIPERLAN/1 (5.15-5.35 GHz). [ABSTRACT FROM AUTHOR]

The corrosion behaviour of carbon steel in 55% lithium bromide solution containing a complex organophosphonate-molybdate inhibitor has been studied using weight loss tests, electrochemical measurements, SEM and X-ray photoelectron spectroscopy. The results showed that the species provides an excellent inhibition performance in 55% lithium bromide solution. When its concentration reached 0·8 kg m-3 in 55% lithium bromide+0·07 mol dm-3 lithium hydroxide at 240°C, the carbon steel's corrosion rate decreased to 25·02 μm/year, and the anodic passivation region and the passive current density of carbon steel were ∼700 mV and 1 μA cm-2 respectively. At the same time, the capacitance value of electric double layer decreased, and the charge transfer resistance increased. The compact compound film formed on the surface of carbon steel in the inhibited LiBr solution was mainly composed of iron oxide and molybdenum oxide. [ABSTRACT FROM AUTHOR]

LIANG C.-H., YANG C.-Y., LU K.-C., CHU P., CHEN C.-H., CHANG Y.-S., O'BRIEN A.P., BLOOMER M. & CHOU K.-R. (2011) Factors affecting peritoneal dialysis selection in Taiwanese patients with chronic kidney disease. International Nursing Review 58, 463-469 Background: Taiwan has the highest incidence and prevalence of end-stage renal disease (ESRD) in the world with 55 499 ESRD patients on long-term dialysis. Nevertheless, 90.96% of these patients are managed on maintenance haemodialysis (HD), with only 9.03% enrolled in a peritoneal dialysis (PD) programme. Aim: The study aim was to identify the factors affecting Taiwanese patient's selection of PD in preference to HD for chronic kidney disease. Methods: A cross-sectional research design was utilized with 130 chronic renal failure (CRF) patients purposively selected from outpatient nephrology clinics at four separate Taiwan hospitals. Logistic regression was used to identify the main factors affecting the patient's choice of dialysis type. Results: Single-factor logistic regression found significant differences in opinion related to age, education level, occupation type, disease characteristics, lifestyle modifications, self-care ability, know-how of dialysis modality, security considerations and findings related to the decisions made by medical personnel ( P < 0.05). Moreover, multinomial logistic regression after adjustment for interfering variables found that self-care ability and dialysis modality know-how were the two main factors affecting the person's selection of dialysis type. Conclusions: Self-care ability and the person's knowledge of the different types of dialysis modality and how they function were the major determinants for selection of dialysis type in Taiwan based on the results from this study. The results indicate that the education of CRF patients about the types of dialysis available is essential to enable them to understand the benefits or limitations of both types of dialysis. [ABSTRACT FROM AUTHOR]

Differential evolution (DE) is a promising evolutionary algorithm for solving the optimal reactive power flow (ORPF) problem, but it requires relatively large population size to avoid premature convergence, which will increase the computational time. On the other hand, evolutionary programming (EP) has been proved to have good global search ability. Exploiting this complementary feature, a hybrid algorithm of DE and EP, denoted as DEEP, is proposed in this study to reduce the required population size. The hybridisation is designed as a novel primary–auxiliary model to minimise the additional computational cost. The effectiveness of DEEP is verified by the serial simulations on the IEEE 14-, 30-, 57-bus system test cases and the parallel simulations on the IEEE 118-bus system test case. [ABSTRACT FROM AUTHOR]

A phytic acid chemical conversion bath was applied to a sample of AZ31 magnesium alloy in this study; a transparent conversion coating formed subsequently on the sample surface. The test results of this coating with a scanning electron microscope (SEM) showed that there exist compact coatings on the surface of treated magnesium alloy. With the analyses of electronic probe microscopy (EPMA) and IR spectrum, a further study of this coating indicated that the coating was mainly composed of phytate and oxide or hydroxid. Furthermore, The electrochemical tests showed that the phytic acid bath conversion treatment enhanced the corrosion resistance of AZ31 magnesium alloys. The optimal pH of the phytic acid bath was 9.00–10.00. [ABSTRACT FROM AUTHOR]

In order to prepare Ce/Al2O3 composite coating on oxide film quickly, a new process of ac deposition method in a solution containing H2O2 and CeCl3 was introduced. Scanning electron microscopy/energy dispersive X-ray spectroscopy, electron probe microanalyser, X-ray diffractometer and X-ray photoelectron spectroscopy were adopted to analyse the coating. The results showed that the Ce/Al2O3 composite coating was easy to prepare when the Al2O3 film thickness was over 6·8 μm. The Ce sediment was amorphous of cerium (III and IV) hydroxide and located into the pores near the surface of Al2O3 films layer. The forming mechanism of the composite coating was discussed accordingly. [ABSTRACT FROM AUTHOR]

In this article, numerical result obtained using two different commercially available electromagnetic (EM) codes based on an integral equation method are presented. One of the methods solves the integral equation by the method of moments (MoM) using higher order basis functions (the commercially available parallel software named TIDES), and the other one solves the integral equation by MoM with a multilevel fast multipole algorithm (MLFMA) incorporating the RWG basis functions (the commercially available software FEKO). Numerical results indicate that the integral equation solver with higher order basis functions occupies less than 40% of the RAM and the execution time is significantly less when compared with that of using the RWG basis functions along with MLFMA. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1219–1225, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24271 [ABSTRACT FROM AUTHOR]

Performance of amplifying evanescent wave is investigated on the basis of simulation. Three cases of waveguides loading SRR resonators, strip lines and composite meta-materials are analyzed individually. In certain frequencies, these three kinds of arrays all have the ability of evanescent wave amplification. [ABSTRACT FROM AUTHOR]

A novel broadband electromagnetic band-gap (EBG) structure is presented using cascaded mushroom-like structure with different radius of via. Direct transmission method is used to determine the band-gap of the EBG structure. The effects of the radius of via and unit number on the mushroom-like EBG structure are investigated. Two kinds of unit with different via radius are cascaded to enlarge the band-gap of EBG structure, which achieves almost 70%. The simulation and experimental results show that the band-gap covers the stop-band produced by the two uniform configurations with different radius, respectively. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2167–2170, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23598 [ABSTRACT FROM AUTHOR]

A novel dual-mode bandpass filter based on conventional triangular structure is designed in this paper. The filter has the characteristics of compact structure, low insertion loss and so on. Several attenuation poles in the stopband are realized to improve the selectivity of the proposed bandpass filter. The experimented results were in good agreement with simulated results. [ABSTRACT FROM AUTHOR]

A novel bandpass filter with two dual-mode cavities based on the substrate integrated waveguide (SIW) is presented. By making use of the inductive discontinuities in an SIW cavity, two degenerate modes can be excited. Due to the phase difference of the two modes in each cavity, two transmission zeros on each side of the passband are created, so the out-of-band rejection of the filter is significantly improved. An SIW dual-mode filter with a center frequency of 12 GHz has been fabricated and measured. The experimental results agree well with the simulation results. [ABSTRACT FROM AUTHOR]

A novel dual-mode dual-band bandpass filter using meander-loop resonators is proposed in this letter. Different meander-loop resonators are operated for respective passbands. Several finite attenuation poles in stopbands are realized to improve the selectivity of the proposed bandpass filter and isolation between the two passbands. Compact size, dual band and high selectivity characteristics are realized by this type of filter structure. The filter is evaluated by experiment and simulation with very good agreement. [ABSTRACT FROM AUTHOR]

A compact dual-band microstrip filter with equal-length split-ring resonators and 0°-feed structure is proposed in this article. The frequency splitting effect of the equal-length SRRs is described in detail. A 0°-feed structure is introduced and applied to realize additional transmission zeros at finite frequencies. The measurement of the filter is in good agreement with the simulation. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1098–1101, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23288 [ABSTRACT FROM AUTHOR]

This paper presents a novel dual-band banpass filter using microstrip open-loop resonators. A new microstrip unit of dual-band bandpass filter is introduced, which can be used as unit element of duan-band filter design. The two open-loop resonators are treated as passband resonator and stopband resonator in analysis, respectively. A five-pole C-band dual-band bandpsss filter has been designed and fabricated. The measured results show a good agreement with the simulated results. [ABSTRACT FROM AUTHOR]

This paper presents a novel synthesis process for wideband coaxial filter terminated with capacitors. At very high frequency and ultra-high frequency, we make use of helix as series inductor, dielectric disk as series capacitor, gap between inner metal disk and outer metal tube as shunt capacitor. By using the proposed synthesis technology and the extracted element formulas, two wideband quasilumped coaxial filters within different frequency ranges are designed and fabricated. Then they are directly connected to form a diplexer by using coaxial lines as impedance transformers. The diplexer can be used in a transceiver system combining two signals at 235 ∼ 280 MHz (VHF) and 315 ∼ 360 MHz (UHF) into one signal before the transmitted antenna. [ABSTRACT FROM AUTHOR]

A novel design method of dual-band and tri-band band-pass filters is proposed in this paper. A compact loaded open-loop resonator(LOLR) structure is introduced. The resonant frequency response of the resonator is described in detail. A dual-band filter and a tri-band filter are designed with the LOLRs. 0° feed structures are applied to improve the selectivity of the proposed filters. The measurements of the filters are in good agreement with the simulated results. [ABSTRACT FROM AUTHOR]

Differential evolution (DE) is studied in detail for optimal reactive power flow (ORPF) problems. The concept, mechanism, and parameter setting of DE are discussed. Based on the IEEE 14-, 30- and 57-bus system test cases, DE is compared with some basic or improved evolutionary algorithms that have been applied to ORPF. It is found that DE is generally a good algorithm for ORPF and worthy of more attention. However, it is also found that DE requires relatively large populations to avoid premature convergence. The impact of this shortcoming is made clear in the IEEE 118-bus system test case. The effectiveness of parallel computing technology for speeding up the computation of DE-based ORPF is also analysed. [ABSTRACT FROM AUTHOR]

Differential evolution (DE) is a promising evolutionary algorithm for solving optimal reactive power flow problems, but it requires relatively large population to avoid premature convergence. In order to overcome this disadvantage, a novel decomposition and coordination method based on the cooperative co-evolutionary architecture and the voltage-var sensitivity-based power system decomposition technique is proposed and incorporated with DE in this paper. It is implemented with a three-level parallel computing topology on a PC-cluster. Based on the IEEE 118-bus system test case, the effectiveness of the proposed method has been verified by comparison with the parallel basic DE not using the decomposition and coordination technique. [ABSTRACT FROM AUTHOR]

Electromagnetic band-gap (EBG) structures exhibit unique electromagnetic properties that have led to a wide range of applications to the antenna and propagation fields. This paper investigates the performance of a waveguide end-slot phased array (WESPA) antenna integrated with mushroom-like EBG structures. The mushroom-like EBG structure has the advantage of compactness and offers the capability to block the surface wave coupling of the phased array, which provides a possible solution to the "blind spots" problem of the WESPA. Some novel and efficient EBG array configurations are proposed, and an infinite phased array and a finite phased array of 3 × 9 slot elements are analyzed. The tradeoffs and design considerations of EBG structures are discussed to obtain optimum performance. [ABSTRACT FROM AUTHOR]

Some recently developed evolutionary programming (EP) techniques for the optimal reactive power flow (ORPF) problem are investigated. By comparing the performances of four control schemes of the strategy parameter (CSSPs), two principles for designing effective CSSPs are identified and are further used to develop two improved CSSPs. The effectiveness of the Lévy distribution based technique of adaptive fast EP is also studied. The investigations are conducted with simulations on the ORPF problems of the IEEE 14-, 30- and 118-bus standard test systems. [ABSTRACT FROM AUTHOR]

A simple and systematic derivation of strongly well-posed perfectly matched layer (PML) in cylindrical and spherical coordinates is presented. The unsplit-field PML formulations are expressed in terms of the complex coordinate stretching approach which was originally proposed for split-field PML. The well-posed PML formulations include the symmetric hyperbolic system besides some lower order terms which do not affect the well-posedness of the system. Numerical simulations validate the accuracy and efficiency of the unsplit-field PML. [ABSTRACT FROM AUTHOR]

In this paper, analytical formulations are deduced to determine reflection points on cylinders and cones, and even cylinder-cone systems. With these analytical formulations, a parallel UTD code is developed based on MPI using domain decomposition method. Since no data exchanging is needed during the calculation, the parallel code has a relatively ideal speedup. Numerical results show the efficiency of analytical ray-tracing techniques and the parallel code. [ABSTRACT FROM AUTHOR]

This work reports the attempts to perform pulsed-laser ablation in a liquid medium for synthesizing oxide semiconductor nanocrystalline particles. Ultrafine TiO2 nanoparticles were synthesized by pulsed-laser ablation of a titanium target immersed in an aqueous solution of surfactant sodium dodecyl sulfate (SDS) as well as in deionized water. The surfactant concentration dependence of TiO2 nanocrystal formation was systematically characterized by X-ray diffraction, optical transmission spectroscopy, and transmission electron microscopy. The maximum amount of ultrafine anatase nanocrystalline particles (with mean size of 3 nm in diameter) was obtained in an aqueous solution of 0.01 M SDS. A probable formation process was proposed based on laser-induced reactive quenching at plasma-liquid interfaces and surfactant-mediated growth in a liquid solution. [ABSTRACT FROM AUTHOR]

This paper presents the generalized constraint conditions for an arbitrary lossless multiport network in partitioned matrix forms, which involve the constraints at magnitudes, phases and determinant of the scattering matrix. The results show that some special properties of a lossless two-port network, such as quasi-reciprocity, quasi-symmetry, and π-convergence of characteristic phases, can be generalized to a lossless N-port network in partitioned matrix forms. Some examples of lossless networks are given to illustrate the application and validity of the proposed approach in this paper. [ABSTRACT FROM AUTHOR]

Closed-form results for the capacitance of an arbitrarily shaped conducting plate are presented. If the charge density suitable for fringe conditions and the appropriate charge barycentre are supposed, the asymptotic closed-form for the capacitance C can be achieved with high accuracy by simple curve integrals or the superposition of basic triangles. Some typical examples, such as an elliptical plate, a regular polygonal plate and a rectangular plate, are given. [ABSTRACT FROM AUTHOR]

The general form of the electromagnetic problem in general media (including lossy and nonreciprocal media) and with the general boundary conditions (including the reactance boundary) is given, the Green formula and its expressions in electromagnetism are introduced, and the generalized functional is presented. It is shown that the available functionals in the literature are special results of the generalized functional, and new applications are also given on the basis of the generalized functional. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 17: 255–259, 1998. [ABSTRACT FROM AUTHOR]

This paper aims to study the excitation mechanism of Nd3+ ions in Nd-SiOx (x < 2) films. The films were deposited by magnetron co-sputtering followed by a rapid thermal annealing at temperature TA ranging from 600 to 1200 °C. Two different photoluminescence (PL) behaviors have been evidenced in SiOx layers depending on the annealing temperature. For low TA (TA < 1000 °C), the recorded visible PL originates from defects energy levels while for high TA (TA > 1000 °C), the visible emission emanates from recombination of excitons in Si nanoclusters. When doped with Nd3+ ions, the visible PL behaviors of Nd-SiOx films follow the same trends. Nd3+ PL was investigated and its decay rate was analyzed in detail. Depending on the annealing conditions, two types of sensitizers have been evidenced. Finally, maximum Nd3+ PL emission has been achieved at around 750 °C when the number of Nd3+ ions excited by the two types of sensitizers reaches a maximum. [ABSTRACT FROM AUTHOR]

Non-TST behavior has recently attracted a great deal of attention. If such behavior is general, then the standard way in which synthetic chemists rationalize and predict reactivity and selectivity would be at least partially invalid. The work in this article was inspired by recent results which highlighted a departure from the predictions of TST for rationalization of the regiochemical outcome of the hydroboration reaction mechanism, suggesting that the isomeric product ratios arise because of nonstatistical dynamical effects (J. Am. Chem. Soc. 2009, 131, 3130-3131). We suggest, based on new calculations using a weak collision RRKM-Master Equation (ME) model, an alternative interpretation of the experimental results which preserves a statistical reaction model. While it is a common assumption that all intermediates and transition states along the reaction path are in thermal equilibrium with solvent, our ME results show that hot intermediates may react while they are undergoing stepwise relaxation through weak collisions, even in solution. To our knowledge, this work represents the first application of master equation methodology to a solution phase thermal reaction in organic chemistry that cannot be otherwise explained using conventional 1ST. Explicit modeling of solvent and solute dynamics is often prohibitively expensive; however, the master equation offers a cornputationally tractable model with considerable predictive power that may be utilized to investigate whetherstepwise collisional relaxation is prevalent in other polyatomic systems. [ABSTRACT FROM AUTHOR]

Foreign body ingestion is not an uncommon problem encountered in clinical practice. However, the associated complication of bowel perforation and migration of the foreign body to the liver is rare. We report two cases of hepatic foreign bodies identified intra-operatively as toothpicks, with the alimentary tract being the presumed origin. [ABSTRACT FROM AUTHOR]

The emission properties of ZnS nanobelts synthesized through thermal evaporation were investigated by means of scanning near-field optical microscopy. The photoluminescence (PL) images of single nanobelts exhibited a bright line along their length. The local light emission spectra measured over the bright lines showed a green emission peak around 535 nm, which was in good agreement with a PL peak obtained for an ensemble of the nanobelts. From careful scanning-electron-microscopy observations of identical nanobelts, we found that the observed green emission is related to line or planar defects of the ZnS nanobelts. [ABSTRACT FROM AUTHOR]

A compact dual-band bandpass filter using folded tri-section stepped impedance resonators (FTSIRs) is proposed in this article. Resonance characteristics of the tri-section stepped impedance resonator (TSIR) are derived and described in detail. A cross-coupled dual-band filter for WLAN(2.4/5.2 GHz) is designed with four FTSIRs. The measurement of the filter is in good agreement with the simulation. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 407–409, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23110 [ABSTRACT FROM AUTHOR]

This letter reports the synthesis of indium nitride (INN) nanowires on gold-patterned silicon substrates in a controlled manner using a method involving thermal evaporation of pure indium. The locations of these InN nanowires were controlled by depositing gold in desired areas on the substrates. Scanning electron microscopy and transmission electron microscopy investigations showed that the InN nanowires are single crystals with diameters ranging from 40 to 80 nm, and lengths up to 5 µm. Energy dispersive x-ray spectrometry showed that the ends of the nanowires are composed primarily of Au, and the rest of the nanowires were InN with no detectable Au incorporations. The Raman spectra showed peaks at 445, 489, and 579 cm[sup -1], which are attributed to the A[sup 1](transverse optical), E[sub 2], and A[sub 1](longitudinal optical) phonon modes of the wurtzite InN structure, respectively. Photoluminescence spectra of the InN nanowires showed a strong broad emission peak at 1.85 eV. [ABSTRACT FROM AUTHOR]

Monoclinic gallium oxide (β-Ga[sub 2]O[sub 3]) nanowires were synthesized by heat treating a composite material of GaAs and pre-evaporated Au at 1240 °C in dry oxygen atmosphere. The catalytic Au metal generated liquid nanoclusters that serve as reactive sites confining and directing the growth of β-Ga[sub 2]O[sub 3] nanowires during the vapor-liquid-solid growth process. The β-Ga[sub 2]O[sub 3] nanowires have diameters ranging from 20 to 50 nm and lengths of several micrometers. Photoluminescence measurement under excitation at 250 nm shows that the bulk β-Ga[sub 2]O[sub 3] nanowires have a stable blue emission at 475 nm and an ultraviolet emission at 330 nm, which may be related to the defects such as the oxygen vacancy and the gallium-oxygen vacancy pair. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A novel matrix perturbation theory to the eigenequation [A][u] = λ[u] is investigated, in which the perturbation solutions to eigen-value λ and eigenvector [u] are given. One of the applications of the above theory--application in a microwave resonate cavity--is researched. [ABSTRACT FROM AUTHOR]

The conditions for perfect absorption under oblique incidence in a single-layer homogeneous absorber backed by a perfectly conducting plate are derived in this article. The cases corresponding to the two types of polarization of the incidence-wave, perpendicular polarization (TE) and parallel polarization (TM), are discussed, respectively. Some conclusions and curves are given. [ABSTRACT FROM AUTHOR]

For a half-space barrier potential, it has been shown that the potential functions in a shallow region 0 < x < d can be accurately reconstructed by using a generalized Born approximation from the reflection coefficient r(k) at x = 0, and the reconstructed error is notable when x > d. By using the network theory presented in this article, we can transform the reflection coefficient at x = 0 into the one at x = d, from which the potential functions of the region x > d can be accurately reconstructed. Numerical examples are given, which show the applicability of this method. [ABSTRACT FROM AUTHOR]

This article derives a Lindell formulation based on a generalized variational principle. A complex dielectric constant measurement of a small-loss dielectric rod using the Rayleigh--Ritz method gives accurate variational analysis. The concept of complex frequency ω is introduced in general, and the stability of the solution is discussed. When compared with the results of perturbation, it is concluded that the deviation of the algorithm is worthy of more attention. [ABSTRACT FROM AUTHOR]

In this paper, the optical properties of Au-doped rhenium diselenide (ReSe2:Au) single crystals have been reported. The doping effects of the material were characterized by polarization-dependent transmittance, piezoreflectance (PzR), and photoreflectance (PR) measurements in the temperature range of 15–300 K. The indirect energy gap of ReSe2:Au shows a slight redshift with respect to the undoped sample. The low temperature PzR and PR spectra reveal an E1ex feature at E∥b polarization as well as two features, E2ex and E3ex, at E⊥b polarization. The angular dependence of the excitonic feature amplitudes agrees well with Malus’ law. In comparison with the undoped ReSe2, the excitonic transition energies remain practically unchanged, while the broadening parameter of the excitonic transition features slightly increases due to impurity scattering. In addition, the parameters that describe the temperature variations of the band-edge excitonic transitions were evaluated and discussed. [ABSTRACT FROM AUTHOR]

In this study, the optical properties of niobium-doped rhenium disulphide (ReS2:Nb) single crystals have been reported. The doping effects of the material were characterized by polarization-dependent transmittance, photoluminescence (PL), and piezoreflectance (PzR) measurements in the temperature range of 10–300 K. The indirect energy gap of ReS2:Nb shows a slight redshift with respect to the undoped sample. The low temperature PL spectra reveal two near direct band-edge excitonic peaks as well as two additional prominent features at higher energy side. The results agree well with that of the PzR investigation of the sample. In comparison with the undoped ReS2, the excitonic transition energies remain practically unchanged, while the broadening parameter of the excitonic transition features slightly increases due to impurity scattering. In addition, the parameters that describe the temperature variations of the band-edge excitonic transitions were evaluated and discussed. [ABSTRACT FROM AUTHOR]

The synergy between catalysis and plasma chemistry often enhances the yield of chemical reactions in plasma-driven reactors. In the case of CO2 splitting into CO and O2, no positive synergistic effect was observed in earlier studies with plasma reactors, except for dielectric barrier discharges, that do not have a high yield and a high efficiency. Here, we demonstrate that introducing metal meshes into radio frequency-driven plasma reactors increases the relative reaction yield by 20%–50%, while supported metal oxide catalysts in the same setups have no effect. We attribute this to the double role of the metal mesh, which acts both as a catalyst for direct CO2 dissociation as well as for oxygen recombination. [ABSTRACT FROM AUTHOR]

In this paper, a new metamaterial superstrate is proposed to design an ultra-low profile and high-gain antenna. According to the theory of Fabry-Perot (F-P) resonant cavity, the F-P resonant antenna is composed of a fishnet superstrate and a printed patch antenna with a solid ground plane. By designing a negative reflection phase and a high reflection magnitude of the fishnet superstrate, we can obtain the F-P resonant antenna with a low profile. Furthermore, by optimizing the superstrate with a suitable reflection phase value, the distance between the superstrate and the patch antenna can be reduced to zero while still maintaining a high gain. [ABSTRACT FROM AUTHOR]

In this paper, the triangular electromagnetic resonators (TERs) is introduced and investigated. The electric mode at lower frequency and magnetic mode at higher frequency, originating from coupling to the electric field and magnetic field, are validated through the measurement in parallel-plate waveguide system, parameter retrieval algorithm and surface currents distributions. Besides, the double negative properties of TERs-wire structures have been validated through both transmission experiment and phase shift experiment. This new resonators with distinct electric resonance as well as magnetic resonance could provide us a new way to design double negative material. [ABSTRACT FROM AUTHOR]

A novel measurement method of parallel-plate waveguide (PPW) system is introduced to detect the characteristics of left-handed metamaterials (LHMs). A sample of LHM composed of triangular open-loop resonator plus wire structures is proposed and measured by using this PPW system. The measurement results are in good agreement with the simulation results. Furthermore, the parametric retrieval algorithm, the calculated negative phase shift and the simulated subwavelength imaging result are given to validate the authenticity of PPW measurement system, which effectively demonstrates the measured transmission passband is indeed a left-handed passband. [ABSTRACT FROM AUTHOR]

Cellular senescence functions as a tumor suppressor that protects against cancer progression. α-Catulin, an α-catenin-related protein, is reported to have tumorigenic potential because it regulates the nuclear factor-κB (NF-κB) pathway, but little is known about its clinical relevance and the mechanism through which it regulates cancer progression. Here, we found that α-catulin mRNA levels were significantly upregulated in cancer cell lines and clinical oral squamous cell carcinomas, which positively correlated with tumor size (P=0.001) and American Joint Committee on Cancer (AJCC) stage (P=0.004). α-Catulin knockdown in the OC2 and A549 cancer cell lines dramatically decreased cell proliferation and contributed to cellular senescence, and inhibited OC2 xenograft growth. Mechanistic dissection showed that α-catulin depletion strongly induced the DNA-damage response (DDR) in both cell lines, via a p53/p21-dependent pathway in A549 cells, but a p53/p21-independent pathway in OC2 cells carrying mutant p53. Global gene expression analysis revealed that α-catulin knockdown altered cell-cycle regulation and DDR pathways at the presenescent stage as well as significantly downregulate several crucial genes related to mitotic chromosome condensation, DDR and DNA repair systems, which suggests that its depletion-induced cellular senescence might be caused by chromosome condensation failures, severe DNA damage and impaired DNA repair ability. Our study provides evidence that α-catulin promotes tumor growth by preventing cellular senescence and suggests that downregulating α-catulin may be a promising therapeutic approach for cancer treatment. [ABSTRACT FROM AUTHOR]