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A simple optic-fiber Fabry-Perot (FP) sensing technique was proposed and experimentally investigated by using polymer material to connect the ends of two singlemode fibers. Four different polymer materials (benzocyclobutene (BCB), UV88 (Relentless, China), Loctite3525 (HenKel, Germany), and NOA68 (Norland, USA)) filling the FP cavity were used to comparatively study the sensing performance of temperature, strain and refractive index. The result shows that the FP sensor with BCB has excellent repeatability with good linear response to temperature in a wide range from room temperature to 250 °C, which is much larger than that of other three materials (2)) and the best repeatability among the four polymer materials.

Postoperative peritoneal adhesions (PPAs) constitute a common complication of abdominal surgery with a high incidence. Bletilla striata (BS) is an important hemostatic drug used in China for nearly 2000 years. The purpose of this study was to investigate the effect of Bletilla striata on postoperative intestinal adhesion in rats. PPA was induced by cecal wall abrasion, and Bletilla striata was injected to observe its effect on adhesion in rats. The adhesion and inflammation score were assessed through visual observation and histopathologic evaluation. The levels of interleukin-1 (IL-1β), tumor necrosis factor (TNF-α), and interleukin-17F (IL-17F) in abdominal cavity and interleukin-6 (IL-6) in plasma were measured by enzyme-linked immunosorbent assay (ELISA) at 6 hours, 12 hours, 24 hours, and 1 week after operation. The tissue level of transforming growth factor beta-1 (TGF-β1) was also determined by ELISA on the seventh day after surgery. The expressions of collagen and TNF-α were, respectively, detected by Masson trichrome staining and immunohistochemical staining. The expression of TGF-β1 and alpha smooth muscle actin (α-SMA) was detected by Western blot. The result showed that Bletilla striata has obvious preventive effect on PPAs and celiac inflammation of PPAs. Bletilla striata could significantly reduce the level of IL-17F abdominal cavity and IL-6 in plasma. Masson trichrome staining and immunohistochemical staining results showed that Bletilla striata also decreased the expression of TNF-α and collagen. Western blot results showed that Bletilla striata decreased the expression of α-SMA and TGF-β1. Our results suggest that Bletilla striata decreased the development of abdominal adhesion in abrasion-induced model of rats and reduced the expression of the important substance which increased in PPAs. Bletilla striata can be further studied as a new and cheaper antiadhesive substance.

Identifying influential spreaders is of great significance to the information diffusion, the identifying of hub protein, the control of infectious diseases. For multiple spreaders, an ideal situation is that not only the spreaders themselves are influential but also relatively dispersed to effectively reduce overlaps. However, it is difficult to make a good tradeoff between them. In this paper, the maximum connected component decomposition method (MCCD) is proposed to identify influential spreaders in complex networks. In this method, different topological attributes of nodes are comprehensively considered and combined with the decomposition method of maximum connected components (MCC) with the topological features. Firstly, the nodes are reranked according to the comprehensive consideration of network topology information. Then, the nodes with higher rankings in the network are checked. If the size and number of the largest connected components in the network are the smallest after deleting a node, the node is selected as the new spreader. When multiple nodes have the same size and number of the maximum connected components, values of which are minimal in all cases, topology information for other connected components of these nodes is considered. Moreover, the method can identify initial spreaders that are not the highest ranking but have great impacts on the network, including the spreading speed, propagation range, and distribution range of initial spreaders. Experimental studies in the Susceptible–Infected–Recovered (SIR) model are shown in four networks to verify the performance of our proposed method along with seven centrality-based and heuristic methods.

Structured light has developed rapidly as a non-contact active three-dimensional measurement method. The phase coding method based on the principle of structured light embeds the codeword into the intensity of the fringe in the form of phase, which is insensitive to surface contrast, ambient light and camera noise due to the use of phase instead of intensity to determine the code word, so it has stronger robustness. The research progress of three dimensional measurement methods of phase-coding was reviewed, and the three-dimensional measurement principles based on phase encoding was summarized, including the design method of initial phase, the generation method of encoded fringes, phase calculation methods, acquisition and correction of fringe order, and acquisition of absolute phase. Some experimental results were given, and the advantages and disadvantages of the phase coding method were pointed out. Finally, the challenges faced by the technology were discussed, and the future development direction of the field was pointed out.

Binary pattern defocused projection is a promising method of measuring 3D shapes. However, deep or long-distance defocus prevents high-accuracy 3D measurement. The triangle pattern is preferred because of its slight defocus and ability to overcome the nonlinear gamma. Thus, a novel method combining triangle pattern slight defocus with phase shifting is proposed. The proposed method has two merits: (1) Compared with the sinusoidal pattern, the proposed method can overcome the nonlinear gamma. (2) Compared with the binary pattern, it has the advantage of slightly defocusing to an ideal sinusoidal pattern in a short distance. Thus, the measurement error caused by nonlinear gamma and deep defocus is reduced. The RMS error of the proposed method is

With the development of optical communication, the optical attenuator becomes an important passive device. It is widely used in power equalization of DWDM system and photo detectors. Here an optofluidic variable optical attenuator (VOA) based on magnetohydrodynamic drive is presented. This chip uses microfluid and compressible air to adjust optical attenuation, where the fluid-drive technology uses magnetohydrodynamic (MHD) drive. The driving pump consists of two electrodes and a permanent magnet (NdFeB) that under the microfluidic channel. Only several volts voltage is needed in operation. There are no movable mechanical parts in this variable optical attenuator, so its volume is small. This variable optical attenuator has a simple structure and a low voltage advantages, and it is easy to control and integrate. The proposed VOA gives a new method for looking for small, low voltage and adjustable VOAs.

To assess the ability of dual-energy CT (DECT) to separate intravenous contrast of bowel wall from intraluminal contrast, we scanned 16 rabbits on a clinical DECT scanner: n = 3 using only iodinated intravenous contrast, and n = 13 double-contrast enhanced scans using iodinated intravenous contrast and experimental enteric non-iodinated contrast agents in the bowel lumen (five bismuth, four tungsten, and four tantalum based). Representative image pairs from conventional CT images and DECT iodine density maps of small bowel (116 pairs from 232 images) were viewed by four abdominal imaging attending radiologists to independently score each comparison pair on a visual analog scale (-100 to +100%) for (1) preference in small bowel wall visualization and (2) preference in completeness of intraluminal enteric contrast subtraction. Median small bowel wall visualization was scored 39 and 42 percentage points (95% CI 30-44% and 36-45%, both p

A variable optical attenuator (VOA) based on S-shape polymer waveguide is demonstrated at the wavelength λ = 1.55 micron. The VOA consists of straight input and output waveguides, an S-shape waveguide and a pair of deposited electrodes. The cladding material of S waveguide is Poly (methyl methacrylate/disperse red 1) (PMMA/DR1) and the core material of S waveguide is SiON. The refractive index of the polymer cladding at S waveguide is modified by the applied electric voltage. Light scatters at the S waveguide and the VOA has large energy loss in the original state at voltage-off. In the voltage-on state, the refractive index of the polymer of the S waveguide reduces, and energy loss changes as the voltage increases. The attenuation of the VOA can be controled and adjusted by the applied voltage. The beam propagation method(BPM) and finite element analysis are employed to simulate and analyse the VOA. The results show that the VOA has large variable attenuation range of 45.2dB and low insertion loss of 0.8dB.