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We have reported a method to enhance the performance of graphene-Si (Gr/Si) Schottky junction solar cells by introducing Au nanoparticles (NPs) onto the monolayer graphene and few-layer graphene. The electron transfer between Au NPs and graphene leads to the increased work function and enhanced electrical conductivity of graphene, resulting in a remarkable improvement of device efficiency. By optimizing the initial thickness of Au layers, the power conversion efficiency of Gr/Si solar cells can be increased by more than three times, with a maximum value of 7.34%. These results show a route for fabricating efficient and stable Gr/Si solar cells. [ABSTRACT FROM AUTHOR]

BiFeO3 films with in-plane compressive strain of -3.5% were deposited on oxygen-deficient La0.3Sr0.7MnO3-δ buffered SrTiO3(001) substrates. This highly strained BiFeO3 does not relax directly into its rhombohedral parent phase upon increasing the film thickness. Instead, a multi-step path involving structural transitions is observed. The misfit stress is first accommodated by the occurrence of true tetragonal BiFeO3 with c/a ratio of 1.23, then reduced by the transformation to the MC-type monoclinic structure, and finally alleviated through the MC-rhombohedral transition. Moreover, this process enables the formation of strain-driven morphotropic phase boundaries at a stress level much lower than the reported threshold of -4.5%. [ABSTRACT FROM AUTHOR]

The particle-in-cell plus Monte Carlo method is used to simulate a cusped field thruster. Three different values of magnetic field strength are simulated and convergent results are obtained successfully. The simulation results indicate that with the increase of the magnetic field strength, electron density peak tends to move in the radial direction towards the axis of the discharge channel. The central gap area of electron density is decreased due to the stronger electron confinement, which correspondingly reduces the inevitable central electron leak in the cusped field thrusters. However, it is found that the stronger confinement of electrons reduces electron density near the wall, which increases the neutral gas leak there. It is also validated that the main potential drop in the discharge channel appears near the channel exit. With the enhancement of magnetic field strength, potential drops at separatrices increase correspondingly. At the same time, several potential wells and barriers can be found near the wall, which accords well with recent theoretical and experimental results. [ABSTRACT FROM AUTHOR]

The classical Weissinger’s L-method is generalized to the lifting problem for steadily advancing curved wings subject to the wing-in-ground (WIG) effect above a large body of water in subsonic flow, and the free surface defines the boundary between the air and water. Unlike the traditional analysis of the lifting problem, the essential techniques focus on finding the three-dimensional free surface Green’s function generated by the isolated horseshoe vortex in the upper layer of the stratified fluid where the air is regarded as weakly compressible and the water is incompressible. The numerical calculation is implemented using Weissinger’s L-method. Finally, the effects of the curved geometry on WIG effect in the vicinity of a free surface in subsonic flow are discussed. Extensive numerical examples are carried out to show the lift properties for three-dimensional swept and dihedral wings operating in the vicinity of a free surface as a function of the sweep or dihedral angle for different clearance-to-chord ratios and Mach numbers. Interestingly, for high Froude numbers, the free surface effectively becomes rigid, and it can safely be treated as a solid surface. [ABSTRACT FROM AUTHOR]

Background and purpose We aimed to estimate the lifetime cost of Parkinson's disease ( PD) from the societal perspective. Methods A convenience sample of English or Chinese-speaking patients with PD was recruited from a PD and Movement Disorders Centre in Singapore to complete a financial burden questionnaire. Sociodemographic and clinical data were retrieved from hospital databases. Markov cohort model analysis was performed (cycle length, 1-year; duration, death or reached 100 years old). Patients were assumed to progress from one Markov state to the next state or death without skipping states or regressing. All model parameters were based on published local data. Results In 195 patients with PD (median age: 68.9, male: 51.8%), the simulated lifetime cost of PD was Singapore Dollar ( SGD) 60 487 ( EUR purchasing power parity 56 253) per patient. Direct medical, non-medical and indirect cost accounted for 18.8%, 12.8% and 68.4% of total lifetime cost, respectively. The top three components of total lifetime cost were productivity losses (67.6%), pharmacotherapy (11.4%) and home care (8.7%). One-way sensitivity analysis and probabilistic sensitivity analyses revealed that estimates were sensitive to cost at H& Y stage 1, 2 and 2.5 and productivity losses. Conclusions The lifetime cost of PD is evaluated for the first time. This cost is substantial and comparable to the lifetime cost of intracerebral haemorrhage in at least one study. Our study identified several priority areas for research and policy formulation: reducing productivity losses, reducing cost of pharmacotherapy, avoiding hospitalization and reducing home care cost. [ABSTRACT FROM AUTHOR]

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

Background: Magnifying endoscopy with narrow-band imaging (ME-NBI) can more clearly assess the surface pattern and microvascular architecture of gastric lesions. Objective: To evaluate the diagnostic efficacy of ME-NBI in patients with early gastric cancer. Design: Prospective study. Setting: Single academic center. Patients: This study involved 164 suspected gastric lesions in 146 consecutive patients who underwent ME-NBI for additional differential diagnosis before treatment. Intervention: ME-NBI findings were classified into 3 groups based on irregularities, absence of surface pattern, and microvascular architecture. All lesions were treated endoscopically or surgically, and ME-NBI diagnosis was compared with histopathological findings. Main Outcome Measurements: Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of real-time ME-NBI diagnosis were determined. Results: The sensitivity, specificity, and accuracy of ME-NBI were 97.3%, 84.4%, and 90.2%, respectively, in distinguishing between cancerous and noncancerous lesions and were 92.3%, 89.7%, and 90.4%, respectively, in distinguishing undifferentiated from differentiated adenocarcinoma. ME-NBI accurately predicted depth of invasion in 37 of 39 differentiated adenocarcinomas (95%). Limitations: The sample size was relatively small. Conclusions: ME-NBI can successfully distinguish between cancerous and noncancerous lesions and between undifferentiated and differentiated adenocarcinomas. Of the 3 patterns on ME-NBI, type A is mainly characteristic of noncancerous lesions, type B is a good indicator of differentiated adenocarcinoma and intramucosal/superficially invasive cancers, and type C is indicative of undifferentiated adenocarcinoma or differentiated cancer with deep submucosal invasion. [Copyright &y& Elsevier]

In this letter, a novel compact dual-mode tri-band microstrip bandpass filter (BPF) is proposed using three sets of dual-mode resonators, i.e., the quarter-wavelength resonator (QWR) which is designed for the first passband, and two sets of stub loaded resonators (SLR) for the second and third passband, respectively. The center frequencies and bandwidths of three passbands can be flexibly tuned and designed. Multiple transmission zeros can be generated to improve the selectivity. Meanwhile, the BPF can obtain more compact size by adopting the folded resonators and extended feed lines. Finally, a tri-band microstrip BPF prototype with fractional bandwidths 18.3% at 1.8 GHz, 5.5% at 3.6 GHz and 12.2% at 5.25 GHz is designed. The measured results are in good agreement with the full-wave simulation results. [ABSTRACT FROM AUTHOR]

This paper presents lumped dual-frequency impedance transformers for frequency-dependent complex loads. According to different dual-frequency allocations of a complex load in Smith chart, three types of impedance matching networks are presented respectively. Several kinds of lumped circuit blocks are used as basic elements for constructing these transformers with design formula deduced. Various examples are given for describing the design procedures. Good features such as big frequency ratio and big matching bandwidths are demonstrated. These lumped dual-frequency impedance transformers have advantage of much compacter dimensions compared to distributive solutions. [ABSTRACT FROM AUTHOR]