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The biomechanical analysis of stress and strain state of multilayered blood vessels has shown great importance in vascular pathology and physiology. However, there is a lack of method in measuring the mechanical property of each layer of a vascular sample without splitting up the wall.Here we develop a vascular inflation test method based on intravascular optical coherence tomography (IVOCT) imaging and inverse parametric estimation. We propose a three-step inverse parametric estimation method to solve the six constitutive parameters of the GOH models for the intima-media and adventitia of the coronaries simultaneously. A bilayer silicone vascular phantom inflation test and a virtual deformation test using finite element simulated data are conducted to evaluate the accuracy of the proposed method.The virtual deformation test demonstrates that the errors of the constitutive constants are less than 2.56% determined by the proposed inverse parametric estimation method. The stress-strain curves of a bilayer silicone vascular phantom obtained based on the parameters determined by the proposed method match well with those obtained by the uniaxial test.The proposed layer-specific vascular mechanical property measurement method provides a new experimental method for mechanical properties characterization of blood vessels. It also has the potential to be used for patient-specific mechanical properties estimation with IVOCT imaging in vivo.

Optineurin is a widely expressed protein that possesses multiple functions. Growing evidence suggests that mutation or dysregulation of optineurin can cause several neurodegenerative diseases, including amyotrophic lateral sclerosis, primary open-angle glaucoma, and Huntington's disease, as well as inflammatory digestive disorders such as Crohn's disease. Optineurin engages in vesicular trafficking, receptor regulation, immune reactions, autophagy, and distinct signaling pathways including nuclear factor kappa beta, by which optineurin contributes to cellular death and related diseases, indicating its potential as a therapeutic target. In this review, we discuss the major functions and signaling pathways of optineurin. Furthermore, we illustrate the influence of optineurin mutation or dysregulation to region-specific pathogenesis as well as potential applications of optineurin in therapeutic strategies.

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is an airborne fungal disease which always destructs leaf and leads to stagnation of grain filling, decreasing of kernel weight, thin seed and yield loss. Winter wheat Huixianhong is a special germplasm with special characteristics of tolerance or resistance against stripe rust. In order to understand the effect on Huixianhong from stripe rust, we designed two kinds of treatment, inoculation of stripe rust fungi (IH) and artificial immune by bactericide (CK) to study the dynamic of disease process, the grain filling and the thousand-kernel weight (TKW). Our results showed that the incubation period of Hongxinahui was 13.5 days. The prevalence increased from 32.9% at 15 days after jointing to 80.0% at 9 days after booting, and reached to 97.0% at the heading stage. The infection type (IT) was 7 to 9 at the beginning of anthesis. The severity, leaf withered area ratio and disease index at the 15th day after anthesis were 67.17%, 98.17% and 0.6717, respectively. The IH maximum increasing rate of leaf necrosis and chlorosis area was from heading beginning stage to anthesis beginning stage, which increased from 18.66 mm2·d-1 to 21.04 mm2·d-1. The maximum rate of grain filling was 1.25 mg·d-1 at the 18th day after anthesis, which was earlier than that of CK by 3.3 days. The IH thousand-kernel weight Loss (TKWL) was more than that of CK by 6.19%, the stage of heading and amature were 3.0 days and 4.5 days earlier than CK, respectively. The stripe rust infection seriously destructed the photosynthetic function of leaf at the earlier stage of grain filling, i.e. at the beginning of anthesis, which led to the most important biomass loss and the grain filling rate decrease. As far as stripe rust is concerned, Huixianhong is a high susceptible, easily been infected, seriously showing symptoms and most quickly epidemic type but can successfully complete grain filling in high quality. It is a very useful germplasm for creating and selecting special breeding materials against stripe rust.

A novel polarization beam splitter is designed on a slab waveguide platform where light is vertically confined. Planar lenses are formed to collimate and refocus a light beam by converting the phase front of the beam. A planar subwavelength grating of a wedge shape induces the form birefringence, where the transverse electric and transverse magnetic waves have different effective refractive indices and are steered to distinct directions. This design provides low insertion loss (

A highly accurate reflective scheme is developed for analysis of two-dimensional (2-D) waveguide discontinuities by using the fourth-order finite-difference (FD) formula. It is demonstrated that the new method achieves a significantly higher accuracy/computation cost ratio in comparison with the conventional FD method. Furthermore, the advantage of the new method is more pronounced for the case of high-index-contrast structures with small feature sizes

We propose and study a box-shaped waveguide based on Si3N4 which confines the light in a sub-wavelength region. The mode characteristics of the proposed structure have been investigated thoroughly.

The edge-emitting distributed Bragg reflector (DBR) laser with a metal nano-strip grating is proposed. It achieves a high reflectivity with a much shorter grating length of 200μm due to the high refractive index contrast of the metal and the semiconductor. Moreover, the modal coupling (κL) of the grating can be tuned in a wide range by simply changing the design parameters of the metal nano-structure. In this work, the metal grating is investigated by the coupled-wave theory (CWT) and the complex mode matching method (CMMM). Results from these two methods are compared and the effects of changing the grating parameters, such as the spacing of the grating and the core region, the thickness of nano-strips and the duty cycle, are discussed regarding the peak reflectivity and the full-width half-maximum (FWHM) of the reflection spectrum. Further simulation of the laser output with the multi-mode rate equation model demonstrates the single-mode operation for a broad range of the metal grating’s design parameters, thus the design freedom is provided. For various applications of the DBR laser, the requirements such as a shorter cavity length, a lower threshold current, or a very high SMSR can be satisfied by properly setting the design parameters.

Passive optical network (PON) is considered as the most appealing access network architecture in terms of cost-effectiveness, bandwidth management flexibility, scalability and durability. And to further reduce the cost per subscriber, a Fabry-Perot (FP) laser diode is preferred as the transmitter at the optical network units (ONUs) because of its lower cost compared to distributed feedback (DFB) laser diode. However, the mode partition noise (MPN) associated with the multi-longitudinal-mode FP laser diode becomes the limiting factor in the network. This paper studies the MPN characteristics of the FP laser diode using the time-domain simulation of noise-driven multi-mode laser rate equation. The probability density functions are calculated for each longitudinal mode. The paper focuses on the investigation of the k-factor, which is a simple yet important measure of the noise power, but is usually taken as a fitted or assumed value in the penalty calculations. In this paper, the sources of the k-factor are studied with simulation, including the intrinsic source of the laser Langevin noise, and the extrinsic source of the bit pattern. The photon waveforms are shown under four simulation conditions for regular or random bit pattern, and with or without Langevin noise. The k-factors contributed by those sources are studied with a variety of bias current and modulation current. Simulation results are illustrated in figures, and show that the contribution of Langevin noise to the k-factor is larger than that of the random bit pattern, and is more dominant at lower bias current or higher modulation current.

We propose an efficient OOFDM-PON scheme: orthogonal subcarrier multiplexing at the ONU with colorless laser diode, and all-optical FFT at the OLT for high speed demultiplexing. The deterioration caused by laser perturbation is also investigated.

In recent years, the invariant and attractor of dynamical system have obtained considerable attention because in nonlinear system we don’t know whether the equilibrium point exists. Various interesting results on this problem have been report [1–5]. In this paper, we will study invariant sets and attractor of reaction-diffusion equations, and give the particular method on determining invariant sets and attractor by virtue of the properties of operator semigroup[6], nonnegative matrices [7], and differential inequality technique [8].

To explore the reference value of intraoperative ultrasonography in the operative procedure and postoperative treatment with relation to hepatopancreatobiliary surgery. 103 cases of hepatopancreatobiliary operations were collected in our hospital from January 1996 to October 2005, in which 68 cases were males and the others were females, age ranged from 45 to 76 years. Hepatocellular carcinoma were 26 cases, gallbladder carcinoma were 5 cases, cholangiocarcinoma were 6 cases, pancreatic carcinoma were 10 cases and other 56 cases were gall stone and/or choledocholithiasis. Intraoperative ultrasonography with high frequency probe was used in all cases. Some minimal occult focuses was found by intraoperative ultrasonography. We found vascular tumor thrombosis in 70% cases of hepatocellular carcinomas. One case was diagnosed as pancreatic carcinoma before operation and found choledochal tract dilatation concurrently with cholangitis by intraoperative ultrasonography. Eight cases of gallstones with no choledochal stones before operation were found by intraoperative ultrasonography that stone lain in low segment of common bile duct. The image data of high quality obtained by intraoperative ultrasonography could not only direct our more proper operative practice but also favor us to make more reasonable postoperative treatment plan.

In this paper, we obtain the methods to determine the domain of exponential attraction of a class of nonlinear discrete systems with delays. Examples are given to show the applicability of the proposed approach.