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Ghrelin has been thought of as a potential link between energy homeostasis and fertility. The aim of this study was to evaluate levels of ghrelin in obese and non-obese systemic lupus erythematosus (SLE) patients, and to reveal a possible association between ghrelin and Anti-Mullerian hormone (AMH) in SLE patients.One hundred SLE patients (50 obese and 50 non-obese subjects) at childbearing age and 100 age-matched healthy controls (50 obese and 50 non-obese subjects) were included. Ghrelin and leptin were examined by enzyme-linked immunosorbent assay. AMH was tested through electrochemiluminescence. Demographics, clinical and laboratory indicators were obtained from medical records.Ghrelin levels were significantly lower in obese SLE patients than non-obese SLE patients (P = .000) and obese controls (P = .002). Non-obese SLE patients and non-obese controls had similar ghrelin levels. Ghrelin levels were correlated positively with AMH (r = .2683, P = .0070) in SLE patients. And ghrelin were negatively associated with leptin (r = -.1969, P = .0496) and BMI (r = - .2401, P = .0161).Our results provide evidence for a potential relationship between ghrelin and AMH in SLE patients, indicating that ghrelin may play a part in energy homeostasis and ovarian damage of SLE patients.

A promising technique to enhance absorption of light in organic solar cells, “ternary approach” represents an important function in improving the device performance. We combined one small molecule dye (5,8-di(benzofuran-2-yl)-2,3-diphenylquinoxaline) (DB-Qx) with [6, 6]-phenyl C71 butyric acid methyl ester (PC71BM) (as the electron acceptor) and poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiopheneco-3-fluorothieno[3,4-b]thiophene-2-carboxylate] (PTB7-Th)(as the electron donor polymer) to form ternary solar cells. The morphology of the active layer of the ternary blend and hole mobility was potentially enhanced by the addition of a molecular donor. The complementary absorption of the two donors and matching photo-luminesce overlapping of DB-Qx with PTB7-Th contributed to improving the device performance. This means that the molecular donor in the ternary blend has an active function in the morphology. The devices produced PCE of 8.64% in the ternary blend system relative to 5.98% in the binary blend system. And, since the emission of DB-Qx partially overlaps with the absorption of PTB7Th, the transfer of energy from DB-Qx to PTB7-TH can improve the exciton utilization efficiency and achieve enhanced overall power conversion efficiency in this ternary solar cell. In this study, we synthesized a small fluorescent molecule material and constructed efficient ternary blend PSCs. Remarkably, the inverted device DIO-free ternary solar cells boost PCE from 5.98 to 8.64% and also exhibit the combined improvement in JSC and the morphology compared to those of DIO-processed films.

Unmanned aerial vehicle is a promising technology in upcoming wireless networks due to its potential aerial feature and line-of-sight capability. Mobile edge computing systems that rely on unmanned aerial vehicles consider offloading computationally intensive tasks to unmanned aerial vehicle to be executed via a powerful edge server. In this paper, we exploit the power of device-to-device communications in terms of low latency and low-power transmission as an additional option to edge offloading. Specifically, any smart device that have a nearby device partner can offload part of its task to be executed by his partner. Additionally, we aim to minimize the total energy consumption during the offloading and local computing procedures at smart devices via jointly optimizing the trajectory of the unmanned aerial vehicle, number of bits allocated for both unmanned aerial vehicle and the partner device, and finally task partitioning. We divide the non-convex major problem into two sub-problems which are efficiently solved via alternative optimization. Simulation results reveal the superiority of device-to-device-assisted mobile edge computing systems that rely on unmanned aerial vehicles over counterparts with no device-to-device assistance.

Primary open‐angle glaucoma (POAG) is the second leading cause of irreversible blindness worldwide. Increased endothelin‐1 (ET‐1) has been observed in aqueous humour (AH) of POAG patients, resulting in an increase in the out‐flow resistance of the AH. However, the underlining mechanisms remain elusive. Using established in vivo and in vitro POAG models, we demonstrated that water channel Aquaporin 1 (AQP1) is down‐regulated in trabecular meshwork (TM) cells upon ET‐1 exposure, which causes a series of glaucomatous changes, including actin fibre reorganization, collagen production, extracellular matrix deposition and contractility alteration of TM cells. Ectopic expression of AQP1 can reverse ET‐1‐induced TM tissue remodelling, which requires the presence of β‐catenin. More importantly, we found that ET‐1‐induced AQP1 suppression is mediated by ATF4, a transcription factor of the unfolded protein response, which binds to the promoter of AQP1 and negatively regulates AQP1 transcription. Thus, we discovered a novel function of ATF4 in controlling the process of TM remodelling in ET‐1‐induced POAG through transcription suppression of AQP1. Our findings also detail a novel pathological mechanism and a potential therapeutic target for POAG.

As formaldehyde is an extremely toxic volatile organic pollutant, a highly sensitive and selective gas sensor for low-concentration formaldehyde monitoring is of great importance. Herein, metal-organic framework (MOF) derived Pd/PdO@ZnO porous nanostructures were synthesized through hydrothermal method followed by calcination processes. Specifically, porous Pd/PdO@ZnO nanomaterials with large surfaces were synthesized using MOFs as sacrificial templates. During the calcination procedure, an optimized temperature of 500°C was used to form a stable structure. More importantly, intensive PdO@ZnO inside the material and composite interface provides lots of p-n heterojunction to efficiently manipulate room temperature sensing performance. As the height of the energy barrier at the junction of PdO@ZnO exponentially influences the sensor resistance, the Pd/PdO@ZnO nanomaterials exhibit high sensitivity (38.57% for 100 ppm) at room temperature for 1-ppm formaldehyde with satisfactory selectivity towards (ammonia, acetone, methanol, and IPA). Besides, due to the catalytic effect of Pd and PdO, the adsorption and desorption of the gas molecules are accelerated, and the response and recovery time is as small as 256 and 264 s, respectively. Therefore, this MOF-driven strategy can prepare metal oxide composites with high surface area, well-defined morphology, and satisfactory room-temperature formaldehyde gas sensing performance for indoor air quality control.

In search for novel cathode materials for lithium, sodium, and potassium ion batteries, organic electrode materials are expected to be the next powerful candidates owing to their high theoretical c...

Taxane-based chemotherapy-loaded drug delivery systems have great potential for cancer treatment. The docetaxel (DTX)-loaded PAMAM-based poly (γ-benzyl-l-glutamate)-b-d-α-tocopheryl polyethylene glycol 1000 succinate (PAM-PBLG-b-TPGS) nanoparticles and the docetaxel (DTX)-loaded PAMAM-based poly (γ-benzyl-l-glutamate) (PAM-PBLG) nanoparticles were designed using a modified nanoprecipitation method. The particle size, encapsulation efficiency (EE), and in vitro release characteristics of the nanoparticles were tested. The effects of the two nanoparticles on the cellular uptake and cell viability on human cervical cancer cell line Hela and the human breast cancer cell line MCF-7 were compared. Furthermore, their antitumor efficiency was evaluated through in vivo tumour growth experiment in comparison with free DTX. PAM-PBLG-b-TPGS nanoparticles displayed high EE, smaller diameter, and a nice releasing profile. Besides, based on the high EE and 'self-controlled' drug release of the DTX-loaded PAM-PBLG-b-TPGS nanoparticles, they exhibited stronger cytotoxicity (lower survival rate) and higher uptake rate than DTX-loaded PAM-PBLG nanoparticles in Hela cells and MCF-7 cells. Furthermore, compared with DTX-loaded PAM-PBLG nanoparticles and free DTX, DTX-loaded PAM-PBLG-b-TPGS nanoparticles produced a potent anti-tumour effect. Thus, the DTX-loaded PAM-PBLG-b-TPGS nanoparticles provide a novel attractive nanocarrier for the DTX delivery of chemotherapy to human breast cancer cells and human cervical cancer cells.

Unmanned aerial vehicle (UAV) nowadays is a promising technology for boosting wireless connectivity, especially for upcoming 5G wireless networks. Due to its aerial feature, potential mobility and flexible deployment, the UAV can provide service in some specific scenarios such as post-disaster network recovery or no-infrastructure terrains. However, the problem of interference management between deployed UAV and underlaying heterogeneous networks, which guarantees the quality of service, is still a challenging task. In this paper, we address the outage probability for UAV connected users and device-to-device (D2D) receivers simultaneously operating in D2D underlaying NOMA UAV-assisted networks, and we derive its closed-form expressions, which turns out to be very accurate. We also solve the power control optimization problem via relaxing the non-convex problem into solving successive low-complexity linear programs to obtain a sub-optimal solution to the problem. The simulation results in confirm the superiority of the proposed approach in the terms of computational complexity and its compromise in the terms of sum rate.

We propose a new circular photonic crystal fiber (CPCF), which can support orbital angular momentum (OAM) modes as many as 110 in C and L communication bands. Using finite element method (FEM), the characteristics of the CPCF for different OAM modes are systematically studied. The numerical analysis shows that most eigenmodes effective index differences are at the order of 1 0 − 3 , which is helpful to reduce the mode coupling and ensure stable OAM modes transmission. Moreover, the nonlinear coefficient is relatively low, with the values for most modes are within 2.80 W − 1 ∕ km at 1.55 μ m. In addition, the confinement loss of most eigenmodes possesses low values under 10−7 dB/m. Besides, all of the OAM modes have relative flat dispersion. In brief, the designed CPCF features large effective index contrast, small nonlinear coefficient, low confinement loss and relatively flat dispersion, which could find potential application in high capacity OAM mode division multiplexing (MDM) fiber communication systems.

The battery industry has been growing fast because of strong demand from electric vehicle and power storage applications.Laser welding is a key process in battery manufacturing. To control the production quality, the industry has a great desire for defect inspection of automated laser welding. Recently, Convolutional Neural Networks (CNNs) have been applied with great success for detection, recognition, and classification. In this paper, using transfer learning theory and pre-training approach in Visual Geometry Group (VGG) model, we proposed the optimized VGG model to improve the efficiency of defect classification. Our model was applied on an industrial computer with images taken from a battery manufacturing production line and achieved a testing accuracy of 99.87%. The main contributions of this study are as follows: (1) Proved that the optimized VGG model, which was trained on a large image database, can be used for the defect classification of laser welding. (2) Demonstrated that the pre-trained VGG model has small model size, lower fault positive rate, shorter training time, and prediction time, so, it is more suitable for quality inspection in an industrial environment. Additionally, we visualized the convolutional layer and max-pooling layer to make it easy to view and optimize the model.

The traditional algorithm has achieved good recognition for the recognition of most characters, but the recognition rate of the number “0” and the letter “O” is only 80-90%, which is difficult to meet the actual needs of the industry. For the recognition of these two characters, a recognition method based on deep learning is proposed. First, image preprocessing is performed on the characters, and then the sample data is manually labeled, and 40,000 training samples and 10,000 test sample images are obtained by the data samples enhancement. The results show that the CNN network can achieve more than 99% recognition rate, the training sample time is about 5 minutes, and 1000 images can be recognized in 1 second. Both the recognition speed and the recognition effect can meet the actual needs of the industry.

Based on the Rytov approximation theory, the transmission model of an orbital angular momentum (OAM)-carrying partially coherent Bessel–Gaussian (BG) beams propagating in weak anisotropic turbulence is established. The corresponding analytical expression of channel capacity is presented. Influences of anisotropic turbulence parameters and beam parameters on channel capacity of OAM-based free-space optical (FSO) communication systems are discussed in detail. The results indicate channel capacity increases with increasing of almost all of the parameters except for transmission distance. Raising the values of some parameters such as wavelength, propagation altitude and non-Kolmogorov power spectrum index, would markedly improve the channel capacity. In addition, we evaluate the channel capacity of Laguerre–Gaussian (LG) beams and partially coherent BG beams in anisotropic turbulence. It indicates that partially coherent BG beams are better light sources candidates for mitigating the influences of anisotropic turbulence on channel capacity of OAM-based FSO communication systems.

In the daily life, there is a tremendous need of fast monitoring of mixture gases and corresponding concentration estimation. For example, in the petrochemical industry, toxic and flammable gases, such as carbon monoxide, methanol and ethanol always co-exist. Without fast and accurate gas species identification and concentration detection system, great security risks will exist. Here, we propose to use an electronic nose system consisting of attention mechanism equipped recurrent neural network with double loss function (2L-ARNN) algorithm to achieve above tasks simultaneously. Firstly, an end-to-end encoder and decoder frame is applied to offer the flexibility to process variable length of the input. Then a novel gated recurrent unit network facilitates the automatic feature extraction from temporal dynamic behaviour. Based on this, attention mechanism dynamically assigns weight vectors of the gas features, which strengthens the robustness for the concentration fluctuation scenarios. Finally, with double loss function, both targets of mixture gas identification and concentration calculation are achieved using the same network. Consequently, within 5 s, 2L-ARNN algorithm has probably an accuracy of 97.67 % for air, CO, ethylene and methane mixture gases, which is significantly improved compared to classical methods. Simultaneously, the estimated normalized root mean squared errors for CO, ethylene, methane are 6.20 %,7.86 % and 5.71 %, which is 6% smaller than that of convolutional neural network. Therefore, our proposed algorithm features fast processing rate, superior accuracy for both gas identification and concentration estimation with improved anti-interference capability for wide-range of mixture gases conditions are essential for real-time gas monitoring systems.

Nowadays featuring outstanding eco-friendliness, the phytochemical fabrication method of nanostructures is very popular. Here, we propose to utilize the Astragalus membranaceus extract as the reducing and capping agent to stabilize the metal and to avoid the aggregations of nanoparticles during ZnO nanoflowers synthesis procedure. As a result, the whole fabrication procedure was highly efficient and cost-effective without requiring a special environment of high pressure or elevated temperature and without chemical hazards used or produced. After the fabrication, detailed characterization about material morphology and crystal structure was carried out, including scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscope (FTIR). Moreover, the ZnO nanoflowers demonstrated distinctive antibacterial, antioxidant and electrochemical sensing effect. Specifically, ZnO nanoflowers had an antibacterial inhibition zone of 19(±0.7) and 15(±0.8) mm in diameter against the concentration of 50 μL (1 mg/mL) Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which is greatly improved compared to the reference drug (Kanamycin). Besides, antioxidant activity was also tested using H2O2 free radical scavenging assay and 60% 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition of 0.5 mg/mL was reported. Finally, controlled by the diffusion process during the charge transfer procedure, 4-nitorphenol was dramatically reduced and a limit of detection of 0.08 μM by ZnO nanoflowers modified electrode was observed during the cyclic voltammetry (CV) experiment. Because the phenolic compounds originating from Astragalus membranaceus helped to facilitate the electron transfer, the limit of detection was lower compared to other materials, such as copper oxide nanoparticles (Cu2O-NPs), silicon dioxide/silver nanoparticles (SiO2/Ag-NPs), zinc oxide nanoparticles (ZnO-NPs), activated carbon (AC) and cobalt oxide nanocubes (Co3O4). Therefore, featuring easy operation, low-cost and eco-friendliness, our proposed ZnO nanoflowers fabrication method will have a great potential in biomedical and electro-catalytic fields.

With the wide applications of power battery in the automobile industries, the safety of power battery is becoming an increasingly prominent problem. At present, a safety vent welded on the battery plate could prevent unpredictable explosions. To perform quality control, the inspection of laser welding defects on safety vent is a critical issue. In this paper, based on the theory of convolutional neural network (CNN) and the technique of transfer learning, a pre-trained SqueezeNet model with small model size and low computation complexity was proposed. We totally collected 34537 images from the production line, and built a 2-classifications dataset and a 7-classifications dataset respectively. It proves that our proposed model achieved better accuracy than the other six contrastive CNN models in these two classification tasks. Specifically, it obtained an accuracy of 99.57 % in the 2-classifications task and an accuracy of 95.58 % in the 7-classifications task. Besides, the model features lightweight and high-speed with only 1.2 MB model size and 4.9 ms average test time; so, it is more suitable for welding quality inspection of safety vent in an industrial production line. Additionally, we ported our pre-trained SqueezeNet and the other four contrastive models to Raspberry Pi embedded system to evaluate their response time. Our proposed model has achieved well response time of less than 330 ms. Our experiments indicate that the proper CNN model can help to conduct the laser welding quality inspection tasks that are usually performed by humans.

Ghrelin is a circulating peptide hormone, which involved in promoting feeding and regulating energy metabolism in human and rodents. Abnormal synovial hyperplasia is the most important pathologic hallmark of rheumatoid arthritis (RA), which is characterised by tumor-like expansion. Existing studies indicated that there may exist some relation between the decreased ghrelin and the abnormally proliferating synovial cells in RA. Therefore, the aim of this study is to explore the apoptotic effects of ghrelin on MH7A synovial cells in vitro. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate the effects of ghrelin on the viability of MH7A cells. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling (TUNEL) and flow cytometry were used to test the apoptotic effects of ghrelin. At last, Western blot and real-time PCR were performed to explore the expression of caspases-8, -9, and -3 after the treatment of ghrelin. MTT experiments showed that ghrelin could inhibit viability of MH7A cells. The results of flow cytometry and TUNEL showed that ghrelin could induce apoptosis of MH7A synovial cells. Western blot showed that expression of cleaved-caspases-8, -9, and -3 were increased in ghrelin stimulation group compared with the control group, while expression of pro-caspases-8, -9, and -3 had no significant difference. In mRNA levels, ghrelin can decrease pro-caspases-8, -9, and -3 mRNA expression, which confirmed the results of protein levels. Then these apoptotic effects were significantly reversed by [D-Lys3] GHRP-6 (ghrelin receptor antagonist). This study found that ghrelin can induce apoptosis of MH7A cells through caspase signaling pathways.

Plasmonic waveguides, as a competitive candidate, have been widely studied in rapid developing photonic integrated circuits (PICs) and optical interconnection fields. However, crosstalk between plasmonic waveguides is a critical issue that has to be considered in practice. Actually, crosstalk dominates the ultimate integration density of the planar photonic circuits. This paper reviews the recent research work on evaluation methods and crosstalk suppression approaches of plasmonic waveguides. Three crosstalk evaluation methods based on comparison of specific parameters of waveguides have been summarized. Furthermore, four specific approaches to reduce crosstalk have been illustrated as two categories according to their impacts on waveguide performances and the whole circuit. One means of crosstalk suppression is changing the placement of waveguides, which could maintain the transmission characteristics of the original waveguide. The other means is inserting medium, which has the advantage of occupying smaller space compared to the first method. Consequently, to suppress crosstalk between plasmonic waveguides, one should choose suitable approach.

We present what we believe is a novel directional coupler based on an elliptic cylindrical nanowire hybrid plasmonic waveguide. Using the finite element method, the electric field distributions of y-polarized symmetric and antisymmetric modes of the coupler are compared, and the coupling and transmission characteristics are analyzed; then the optimized separation distance between the two parallel waveguides, 100 nm, is obtained. This optimized architecture fits in the weak coupling regime. Furthermore, the energy transfer is studied, and the performances of the directional coupler are evaluated, including excess loss, coupling degree, and directionality. The results show that when the separation distance is set to 100 nm, the coupling length reaches the shorter value of 1.646 μm, and the propagation loss is as low as 0.076 dB/μm, and the maximum energy transfer can reach 80%. The proposed directional coupler features good energy confinement, ultracompact and low propagation loss, which has potential application in dense photonic-integrated circuits and other photonic devices.

The Co 3 O 4 coated Al composites with different Co 3 O 4 content were synthesized by a rheological phase reaction in combination with a following heat-treatment process. The composites were characterized by X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, galvanostatic cycling and ac impedance spectroscopy. Results revealed that Al matrix is coated by Co 3 O 4 nanoparticles to form a core-shell structure. The composites exhibit improved cycle performance than pure Al particles. After ten cycles, the capacity retentions of Al-1 wt.% Co 3 O 4 , Al-3 wt.% Co 3 O 4 and Al-5 wt.% Co 3 O 4 are 66.8, 69.9 and 70.1% respectively, which are much higher than that of pure aluminum (42%). The improvement of cycle performance is related to the formation of core-shell structure, which plays important roles in the enhancement of mechanical stability and the reinforcement of electronic contact.

We report the optimization design and experimental results for the imaging properties of a photon sieve, which is formed on a layer of metal film supported by a thin glass substrate. As an example, we considered a micro-optical element with parameters of diameter D = 50 mm, 3,564,290 hole number, and 10 mu m minimum micro-hole diameter, which was designed and fabricated by means of surface machining technique in the lab. To evaluate its imaging performance, both on-axis and off-axis imaging experiments were carried out using the element. Compared to a Fresnel zone plate lens with the same feature size, the photon sieve has super imaging performance. Some quantitative analyses and initial qualitative explanations were given for the imaging characteristics. (C) 2007 Elsevier Ltd. All rights reserved.

Plasmonic nano-structures are one of the most exciting topics in the field of nano-materials. The fabrication process and the plasmon-related optical properties of unpenetrated metallic films with periodic rectangular hollows were studied in this paper. The results show that for frequencies close to the surface plasmon band, a high transmission of optical waves is possible even in an unpenetrated metallic structure. The near-field studies show that the field enhancement due to metallic nano-structures play a key role for high transmission in the case of unpenetrated metallic films with periodic rectangular hollows. The corrugation on the input side transfers light into surface plasmon, which results in high intensity of electric field located in the grooves, and the periodic metals on the exit side are responsible for scattering of plasmon into transmitted light. The optical properties of the unpenetrated metallic films with periodic rectangular hollows can be used in many fields such as nano-optics devices, biological sensors, chemical reactors, etc.

The mechanism and kinetics of the curing reaction of cyanate ester (CE) resin modified with polyethylene glycol were investigated by means of differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The relationship of heat flow versus conversion rate was used to evaluate the effects of polyethylene glycol (PEG) on the curing reaction of CE. DSC results showed that the addition of PEG decreased the curing temperature of CE effectively when its content was less than 20 wt %. The curing behavior of CE/PEG still complies with the self-catalytic kinetic model proposed by Kamal. The effects of PEG content on the kinetics parameters and conversion rate of the curing reaction were discussed. FTIR results indicated that the –OH groups in PEG participated in the polymeric reaction of CE and formed –O–C (=NH) –O– structure through block copolymerization, which extended the chain length between triazine rings and reduced the density of triazine rings. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41841.

The spatial distribution of the interference of surface plasmon polariton (SPP) on metallic nanostructures has been studied. The results show that the transmission of electromagnetic radiation is remarkably enhanced for frequencies close to the surface plasmon band and the interference of SPP can redistribute the illumination light into subwavelength-scale spatial distribution with high intensity, which beats the Rayleigh diffraction limit. For an appropriate thickness, the transmission of an unperforated structure can be larger than that of holes or slits systems with the same periodicity and thickness when the coupled surface plasmon wave mode is excited. With the help of the interference of the horizontal plasmon excited by Bragg resonance due to the periodicity in the horizontal direction, the vertical plasmons, excited in z direction via Fabry–Perot cavity resonance in different grooves, are correlated, so the transmission is increased via the tunneling process. The properties of transparency for light but impenetrability for gas and liquid will be of importance for device applications. The information on near-field distribution from perforated metallic structures is important for understanding the underlying physics, as well as for optimizing photonic crystals for possible applications.

We propose a new kind of hybrid plasmonic waveguide structure, namely the semiconductor nanowire -insulator-metal strip waveguide, or SNIMS. It has been demonstrated using Finite Element Methods (FEM) that this structure support hybrid plasmonic modes traveling over large distances(100~330um) with strong mode confinement (ranging from λ2/300 to λ2/30) at telecom wavelengths. The result is better than that of a traditional semiconductor waveguide. In addition，we stimulated a coupler based on the SNIMS structure. The coupling length Lc can be as short as 2.2um when the separation D=400nm . In other words, this device can be used as a highly compact directional coupler.

Optimization of hyperlens structure and composition of materials is a key problem for its application in biological imaging and nanometer lithography. This paper systematically optimizes and analyzes overall structure of the curved multilayer hyperlens. The influences of structure parameters, such as layer number, layer thickness, filling ratio, permittivities, curvature radius, thickness of photoresist (PR) and reflector layer (PRL) are numerically emulated. It shows that the full width at half maximum (FWHM), the contrast and the electric field intensity of the output beam can be comprehensively influenced by these parameters. As a result, Ag and Al2O3 is the best metal and dielectric,less layer number and thinner layer thickness will be better, the optimal size of the curvature radius may fluctuate for practical fabrication of hyperlens, Ag is the best selection for PRL and Cu can sometimes be the substitute for decreasing the cost, The optimal PRL thickness varies from 40 to 80nm and the optimal range of PR thickness is between 30 nm and 50nm. Keywords-metarmaterial;hyperlens;parameters optimazation ;surface plasmon;FDTD solution

Multilayer silver superlenses had been shown to having sub-wavelength performance. In this paper, we investigate the effects on imaging performance of different multilayer imaging structures comprising alternately layered metal and dielectric films. We first compare and analyze transmission coefficients of different structures by changing the layer thickness ratio, the total thickness of the layers and the dielectric materials. Then we simulate the imaging performance by the finite difference time domain (FDTD) method of these multilayered superlenses. According to the analyzing and simulated results, a multilayer silver superlens with optimum structure is suggested. Keywords-Superlens; Surface plasmons; Photolithography; Imaging performance

Background The role of human papilloma virus (HPV) in oral lichen planus (OLP) is controversial. Objectives The primary aim of the current study is to calculate the pooled risk estimates of HPV infection in OLP when compared with healthy controls. Methods Bibliographic searches were conducted in three electronic databases. Articles on the association between HPV and OLP were selected from case-control studies or cross-sectional studies, following predefined criteria. Pooled data were analyzed by calculating odds ratios (OR) and 95% confidence interval (CI). Results Of the 233 publications identified, 22 case-control studies met the inclusion criteria. Collectively, 835 cases and 734 controls were available for analysis. The summary estimate showed that OLP patients have significantly higher HPV prevalence (OR: 6.83; 95% CI: 4.15-11.27) than healthy controls. In subgroup analyses, the association of HPV and OLP varied significantly by geographic populations. The ORs ranged from 2.43 to 132.04. The correlation of HPV and erosive-atrophic oral lichen planus (EA-OLP) (OR: 9.34) was comparable and well above that of HPV and non-EA-OLP (OR: 4.32). Among HPV genotypes, HPV 16 showed an extremely strong association with OLP (OR: 11.27), and HPV 18 showed a relatively strong one (OR: 6.54). Conclusion In conclusion, a significant association was found between HPV and OLP. The strength of the association varied across geographic populations, clinical types of OLP, and HPV genotypes. The results suggest that HPV might play an important causal role in OLP and in its malignant to progression.

A plasmonic Bragg reflector with rectangular-shaped transmission spectrum based on MIM (Metal-Insulator-Metal) waveguides is proposed and theoretically analyzed in this paper. As the MIM waveguide structure is treated as a cascade structure of multi-F-P cavities and by use of Transfer Matrix Method (TMM), the property parameters of the reflector is related to the structure parameters of grating, so that the performance index of reflector can be optimized. As an example, a wide bandgap reflector is designed by this method, the center-wavelength of it at 1550nm, the full width at half maximum (FWHM) of it at 640nm and the center-transmission of it approaching zero.

We researched an elliptic cylindrical silicon nanowire hybrid surface plasmon polariton waveguide and evaluated its mode characteristics using the finite element method software COMSOL. The waveguide consists of three parts: an elliptic cylindrical silicon nanowire, a silver film layer, and a silica covering layer between them. All of the components are surrounded by air. After optimizing the geometrical parameters of the waveguide, we can achieve the waveguide's strong field confinement (ranging from λ2/270 to λ2/27) and long propagation distances (119-485 μm). In order to further understand the impact of the waveguide's architecture on its performance, we also studied the ridge hybrid waveguide. The results show that the ridge waveguide has moderate local field confinement ranging from λ2/190 to λ2/20 and its maximum propagation distance is about 340 μm. We compared the elliptic cylindrical and ridge nanowire hybrid waveguides with the cylindrical hybrid waveguide that we studied before. The elliptic cylindrical waveguide achieves a better trade-off between reasonable mode confinement and maximum propagation length in the three waveguides. The researched hybrid surface plasmon polaritons waveguides are useful to construct devices such as a directional coupler and may find potential applications in photonic integrated circuits or other novel SPP devices.

In this paper, we investigated the electric field profiles and phase distribution at the metal interfaces of the structure, and then analyzed their dependence on the groove depth and distance between slit and grooves though finite-difference time-domain (FDTD) simulation. Calculated results show that variant groove depth generates phase difference periodically, which indicates the existence of standing wave in the groove. The results also show that the phase of the emission at each groove is proportional to the distance travelled by the surface wave in one period. Based on these facts, a simple process of the transmission model is illuminated.

In this paper, we discussed the beam focusing of light emerged from a subwavlength metallic slit surrounded by a set of grooves with constant space and width but variant depth at the exit side surface. Based on the numerical model presented by L. Martin-Moreno, F. J. Garcia-Vidal etc. (published in PRL 167401), we attempted to optimize grooves depth to obtain general beam manipulation, such as beam focusing. This attempt did not prove successful for many cases with variant focal length in our optimization practice, although some specific results display agreeable beam focusing with elongated focal depth. Further numerical computation shows that the excited electromagnetic field intensity around groove openings has a strong dependence on the groove depth, but the phase only vary with a maximum change value of π by tuning the groove depth. This property restricts greatly the modulation of electromagnetic field by just changing each groove depth. More geometrical parameters, including groove space and width, are recommended for optimization in the design of nano metallic groove and slit structures for specific beam manipulation.