Plasma lipid profiles discriminate bacterial from viral infection in febrile children

Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection are often non-specific, and there is no definitive test for the accurate diagnosis of infection. The 'omics' approaches to identifying biomarkers from the host-response to bacterial infection are promising. In this study, lipidomic analysis was carried out with plasma samples obtained from febrile children with confirmed bacterial infection (n = 20) and confirmed viral infection (n = 20). We show for the first time that bacterial and viral infection produces distinct profile in the host lipidome. Some species of glycerophosphoinositol, sphingomyelin, lysophosphatidylcholine and cholesterol sulfate were higher in the confirmed virus infected group, while some species of fatty acids, glycerophosphocholine, glycerophosphoserine, lactosylceramide and bilirubin were lower in the confirmed virus infected group when compared with confirmed bacterial infected group. A combination of three lipids achieved an area under the receiver operating characteristic (ROC) curve of 0.911 (95% CI 0.81 to 0.98). This pilot study demonstrates the potential of metabolic biomarkers to assist clinicians in distinguishing bacterial from viral infection in febrile children, to facilitate effective clinical management and to the limit inappropriate use of antibiotics

Plasma lipid profiles discriminate bacterial from viral infection in febrile children

Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection ar

Measurement Of Wavefront Distortions Resulting From Incidence Of High-Power 2 Μm Laser Light

Wavefront distortions induced in various silica samples by a 2 μm thulium fiber laser were measured. Absorption of silica at 2 μm makes a full characterization of thermal lensing critical for high power applications. © 2011 OSA

Measurement Of Wavefront Distortions Resulting From Incidence Of High-Power 2 Μm Laser Light

Wavefront distortions induced in various silica samples by a 2 μm thulium fiber laser were measured. Absorption of silica at 2 μm makes a full characterization of thermal lensing critical for high power applications. ©OSA/ CLEO 2011

High-Energy Q-Switched Tm\u3csup\u3e3+\u3c/sup\u3e-Doped Polarization Maintaining Silica Fiber Laser

We report the performance of an actively Q-switched Tm fiber laser system. The laser was stabilized to sub-nanometer spectral width using each of two feedback elements: a blazed reflection grating and a volume Bragg grating. Maximum pulse energy using the reflection grating was 325 μJ pulses at 1992 nm (\u3c 200 pm width) with a 125 ns duration at a 20 kHz repetition rate. Maximum pulse energy using the volume Bragg grating was 225 μJ pulses at 2052 nm (\u3c200 pm width) with a 200 ns duration also at 20 kHz. We also report the laser\u27s performance as an ablation source for LIBS experiments on copper. © 2010 Copyright SPIE - The International Society for Optical Engineering

Rapid Thermo-Optical Quality Assessment Of Laser Gain Media

We describe a technique for the quick and simple assessment of doped optical materials for use as laser gain media. To demonstrate this technique, referred to as Rapid Thermo-Optical Assessment (RTOA), we analyze a set of ceramic and crystalline Yb3+:YAG samples. RTOA is based on Shack-Hartmann wavefront sensing and thermal lensing to evaluate the media\u27s thermal response, giving a relative overall quality assessment of the material. The technique is also broadly applicable to optical media considered for high power or thermal loading conditions, and useful for the refinement of fabrication methods

Thermo-Optic Quality Assessment Of Doped Optical Ceramics

The use of optical quality ceramics for laser applications is expanding, and with this expansion there is an increasing need for diagnostics to assess the quality of these materials. Ceramic material with flaws and contaminants yields significantly less efficient performance as laser gain media and can generate excessive amounts of waste heat. This is a concern that is especially relevant in high power laser applications where thermally induced damage can be catastrophic. In order to assess a set of ceramic and crystalline samples we induce and measure thermal lensing in order to produce a relative ranking based on the extent of the induced thermal lens. In these experiments thermal lensing is induced in a set of nine 10% Yb:YAG ceramic and single-crystal samples using a high power 940 nm diode, and their thermal response is measured using a Shack-Hartmann wavefront sensor. The materials are also ranked by their transmission in the visible region. Discrepancies between the two ranking methods reveal that transmission in the visible region alone is not adequate for an assessment of the overall quality of ceramic samples. The thermal lensing diagnostic technique proves to be a reliable and quick over-all assessment method of doped ceramic materials without requiring any a priori knowledge of material properties. © 2013 Copyright SPIE

High Power Thulium Fiber Lasers

Thulium fiber lasers at 2 μm are following a similar development path to ytterbium fiber lasers. We review recent progress exploiting the unique characteristics of these high power lasers in spectral and temporal domains. OCIS codes: (060.3510) Lasers, fiber ©2011 Optical Society of America

High Power Thulium Fiber Lasers

Thulium fiber lasers at 2 μm are following a similar development path to ytterbium fiber lasers. We review recent progress exploiting the unique characteristics of these high power lasers in spectral and temporal domains. OCIS codes: (060.3510) Lasers, fiber ©2011 Optical Society of America

Tunable High Power Thulium Fiber Lasers

Two thulium fiber laser configurations are described providing widely tunable and narrow linewidth output. We show that such systems can produce average powers greater than 100 W. ©2010 IEEE