Optofluidic ring resonator laser with an edible liquid laser gain medium

We demonstrate a biocompatible optofluidic laser with an edible liquid laser gain medium, made of riboflavin dissolved in water. The proposed laser platform is based on a pulled-glass-capillary optofluidic ring resonator (OFRR) with a high Q-factor, resulting in a lasing threshold comparable to that of conventional organic dye lasers that are mostly harmful, despite the relatively low quantum yield of the riboflavin. The proposed biocompatible laser can be realized by not only a capillary OFRR, but also by an optical-fiber-based OFRR that offers improved mechanical stability, and is promising technology for application to in vivo bio-sensing

Experimental Investigation for Tensile Performance of GFRP-Steel Hybridized Rebar

Tensile performance of the recently developed “FRP Hybrid Bar” at Korea Institute of Civil Engineering and Building Technology (KICT) is experimentally evaluated by the authors. FRP Hybrid Bar is introduced to overcome the low elastic modulus of the existing GFRP bars to be used as a structural member in reinforced concrete structures. The concept of material hybridization is applied to increase elastic modulus of GFRP bars by using steel. This hybridized GFRP bar can be used in concrete structures as a flexural reinforcement with a sufficient level of elastic modulus. In order to verify the effect of material hybridization on tensile properties, tensile tests are conducted. The test results for both FRP Hybrid Bar and the existing GFRP bars are compared. The results indicate that the elastic modulus of FRP Hybrid Bar can be enhanced by up to approximately 250 percent by the material hybridization with a sufficient tensile strength. To ensure the long-term durability of FRP Hybrid Bar to corrosion resistance, the individual and combined effects of environmental conditions on FRP Hybrid Bar itself as well as on the interface between rebar and concrete are currently under investigation

Supercontinuum Generation in a Silica Spiral Waveguide

A low-loss silica spiral waveguide is used for demonstrating on-chip supercontinuum generation. The broadest measured spectrum spans an octave (936 – 1888 nm) at −50 dB from peak when 2.17 nJ pulses are launched

Coherent ultra-violet to near-infrared generation in silica ridge waveguides

Short duration, intense pulses of light can experience dramatic spectral broadening when propagating through lengths of optical fibre. This continuum generation process is caused by a combination of nonlinear optical effects including the formation of dispersive waves. Optical analogues of Cherenkov radiation, these waves allow a pulse to radiate power into a distant spectral region. In this work, efficient and coherent dispersive wave generation of visible to ultraviolet light is demonstrated in silica waveguides on a silicon chip. Unlike fibre broadeners, the arrays provide a wide range of emission wavelength choices on a single, compact chip. This new capability is used to simplify offset frequency measurements of a mode-locked frequency comb. The arrays can also enable mode-locked lasers to attain unprecedented tunable spectral reach for spectroscopy, bioimaging, tomography and metrology

Transjugular insertion of biliary stent in patients with malignant biliary obstruction complicated by ascites with/without coagulopathy: a prospective study of 12 patients

PURPOSEIn patients with malignant biliary obstruction complicated by massive ascites, when endoscopy fails, safe routes for biliary decompression are needed as an alternative to percutaneous approach. We aimed to evaluate the safety and effectiveness of transjugular insertion of biliary stent (TIBS) in patients with malignant biliary obstruction complicated by massive ascites with or without coagulopathy.METHODSFrom March 2012 to December 2017, a total of 12 consecutive patients with malignant biliary obstructions treated with TIBS were enrolled in this study. Five patients had jaundice and cholangitis, while seven had jaundice only. Clinical parameters including technical and clinical success rates and complications following TIBS were evaluated. Overall survival and stent occlusion-free survival were assessed using Kaplan-Meier analysis.RESULTSThe indications for transjugular approach were massive ascites with (n=2) or without (n=10) coagulopathy. TIBS was technically successful in 11 of 12 patients. Clinical success was defined as successful internal drainage and was achieved in eight patients. The mean serum bilirubin level was initially 13.9±6.3 mg/dL and decreased to 4.9±5.3 mg/dL within 1 month after stent placement (P = 0.037). Two patients had procedure-related complications (hemobilia). During the follow-up period (mean, 30 days; range, 1–146 days), all 12 patients died of disease progression. The median overall survival and stent occlusion-free survival times were 19 days (95% confidence interval [CI], 16–22 days) and 19 days (95% CI, 12–26 days), respectively. There was no stent dysfunction in the eight patients that had successful internal drainage.CONCLUSIONTIBS appears to be safe, technically feasible, and clinically effective for patients with malignant biliary obstruction complicated by massive ascites with or without coagulopathy

Confirmation of the performance of exfoliated graphite nanoplatelets for pollutant reduction rate on wood panel

Abstract Exfoliated graphite nanoplatelets have been used as an additive for the improvement of a variety of properties. Nowadays, it is used as an adsorbent for pollutants, especially volatile organic compounds and formaldehyde. Additionally, exfoliated graphite nanoplatelets have been used as an additive in wood composites, because wood composites have a higher thermal conductivity than timber or typical wood-based panels. Therefore, exfoliated graphite nanoplatelets have been applied to high-density fiberboard which is a core material of wood flooring for the emission rate reduction of volatile organic compounds and formaldehyde and for increasing the thermal conductivity of wood flooring in radiant floor heating systems. Volatile organic compound emissions have been reduced significantly in wood composite boards according to the addition of exfoliated graphite nanoplatelets. The properties of formaldehyde emission and thermal conductivity decreased when 2% exfoliated graphite nanoplatelets are added to high-density fiberboard. However, these properties increased with the increase in the addition of exfoliated graphite nanoplatelets from 2% to 4%