Plasmonic Demultiplexer and Guiding

Two-dimensional plasmonic demultiplexers for surface plasmon polaritons (SPPs), which consist of concentric grooves on a gold film, are proposed and experimentally demonstrated to realize light-SPP coupling, effective dispersion and multiple-channel SPP guiding. A resolution as high as 10 nm is obtained. The leakage radiation microscopy imaging shows that the SPPs of different wavelengths are focused and routed into different SPP strip waveguides. The plasmonic demultiplexer can thus serve as a wavelength division multiplexing element for integrated plasmonic circuit and also as a plasmonic spectroscopy or filter.Comment: 17 pages, 5 figure

Practical Guide to the Realization of a Convertible Optical Trapping System

In this article, we provide a detailed guide to the construction of a convertible optical trapping system for either single-beam or counter-propagating trap. The single-beam trap maintains all the functionalities that a conventional optical tweezer has. While the counter-propagating trap allows for the trapping of particles that single-beam trap cannot handle. The counter-propagating trap can be easily switched to a single-beam trap, and vice versa. Therefore, this convertible optical trapping system allows for the trapping and manipulation of particles with a wide variety of sizes and materials

Review of Optical Detection of Single Molecules Beyond the Diffraction and Diffusion Limit Using Plasmonic Nanostructures

Single-molecule detection has become a unique and indispensable tool for the study of molecular motions and interactions at the single-molecule level. Unlike ensemble measurement where the information is averaged, single-molecule analysis yields invaluable information on both the individual molecular properties and their microenvironment. Among the various technologies for the detection of single molecules, the detection with optical methods has many advantages in terms of its high sensitivity, electrical passiveness, and robustness. The recent advances in the engineering of either the excitation light or the solution of the molecules have paved the way for enhanced single-molecule detection. We present recent developments and future perspectives for single-molecule detection in the following three regimes: on a dry surface, in solutions at ultralow concentrations, and in solutions at native physiological concentrations

Safety and preventive effects of rivaroxaban and low-molecular-weight heparin on deep vein thrombosis of lower extremity after total hip arthroplasty

Deep vein thrombosis (DVT) is a common complication of skeletal surgery, which can cause disability and death in severe cases. Here, we have compared the preventive effects of rivaroxaban and low molecular weight heparin on DVT of lower extremity after total hip arthroplasty and the safety. A total of 310 patients who received total hip arthroplasty from May 2014 to June 2016 were divided into a rivaroxaban group (n=153) and a low molecular weight heparin group (n=157). The rivaroxaban group was orally administered with rivaroxaban (10 mg, qd) 12 h after surgery for 30 consecutive days, and the other group was subcutaneously injected with low molecular weight heparin calcium injection (0.6 mL, ad) for 7 consecutive days. The incidence rate of lower extremity DVT, drainage blood volume, hemoglobin decline, as well as preoperative and postoperative 7-d prothrombin time (PT), activated partial thromboplastin time (APTT), platelet (PLT) count and D-dimer level of the two groups were compared. The two groups had similar incidence rates of lower extremity DVT, drainage blood volumes and extents of hemoglobin decline (P >0.05). There were no significant differences in the preoperative and postoperative 7-d PT, APTT, PLT counts and D-dimer levels between the two groups (P >0.05). Rivaroxaban and low molecular weight heparin show comparable preventive effects on lower extremity DVT after total hip arthroplasty. Results suggest that rivaroxaban is superior than the low molecular weight heparin in terms of convenient use (oral administration), good compliance and absence of dose adjustment

Differential metabolic responses of clam Ruditapes philippinarum to Vibrio anguillarum and Vibrio splendidus challenges

Clam Ruditapes philippinarum is one of the important marine aquaculture species in North China. However, pathogens can often cause diseases and lead to massive mortalities and economic losses of clam. In this work, we compared the metabolic responses induced by Vibrio anguillarum and Vibrio splendidus challenges towards hepatopancreas of clam using NMR-based metabolomics. Metabolic responses suggested that both V anguillarum and V splendidus induced disturbances in energy metabolism and osmotic regulation, oxidative and immune stresses with different mechanisms, as indicated by correspondingly differential metabolic biomarkers (e.g., amino acids, ATP, glucose, glycogen, taurine, betaine, choline and hypotaurine) and altered mRNA expression levels of related genes including ATP synthase, ATPase, glutathione peroxidase, heat shock protein 90, defensin and lysozyme. However, V. anguillarum caused more severe oxidative and immune stresses in clam hepatopancreas than V splendidus. Our results indicated that metabolomics could be used to elucidate the biological effects of pathogens to the marine clam R. philippinarum. (C) 2013 Elsevier Ltd. All rights reserved.Clam Ruditapes philippinarum is one of the important marine aquaculture species in North China. However, pathogens can often cause diseases and lead to massive mortalities and economic losses of clam. In this work, we compared the metabolic responses induced by Vibrio anguillarum and Vibrio splendidus challenges towards hepatopancreas of clam using NMR-based metabolomics. Metabolic responses suggested that both V anguillarum and V splendidus induced disturbances in energy metabolism and osmotic regulation, oxidative and immune stresses with different mechanisms, as indicated by correspondingly differential metabolic biomarkers (e.g., amino acids, ATP, glucose, glycogen, taurine, betaine, choline and hypotaurine) and altered mRNA expression levels of related genes including ATP synthase, ATPase, glutathione peroxidase, heat shock protein 90, defensin and lysozyme. However, V. anguillarum caused more severe oxidative and immune stresses in clam hepatopancreas than V splendidus. Our results indicated that metabolomics could be used to elucidate the biological effects of pathogens to the marine clam R. philippinarum. (C) 2013 Elsevier Ltd. All rights reserved

Optothermal Microbubble Assisted Manufacturing of Nanogap-Rich Structures for Active Chemical Sensing

Guiding analytes to the sensing area is an indispensable step in a sensing system. Most of the sensing systems apply a passive sensing method, which waits for the analytes to diffuse towards the sensor. However, passive sensing methods limit the detection of analytes to a picomolar range on micro/nanosensors for a practical time scale. Therefore, active sensing methods need to be used to improve the detection limit in which the analytes are forced to concentrate on the sensors. In this article, we have demonstrated the manufacturing of nanogap-rich structures for active chemical sensing. Nanogap-rich structures are manufactured from metallic nanoparticles through an optothermally generated microbubble (OGMB) which is a laser-induced micron-sized bubble. The OGMB induces a strong convective flow that helps to deposit metallic nanoparticles to form nanogap-rich structures on a solid surface. In addition, the OGMB is used to guide and concentrate analytes towards the nanogap-rich structures for the active sensing of analytes. An active sensing method can improve the detection limit of chemical substances by an order of magnitude compared to a passive sensing method. The microbubble assisted manufacturing of nanogap-rich structures together with an active analyte sensing method paves a new way for advanced chemical and bio-sensing applications