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Presents a study that analyzed preionization electron densities in an x-ray preionized xenon chloride (XeCl) laser as a function of the gas composition. Characteristics of XeCl lasers; Illustration of the laser chamber and x-ray source used in the experiment; Analysis of the charge production mechanisms.

Presents a study which examined the initial electron density in x-ray preionized avalanche discharge lasers. Experimental details; Results and discussion; Conclusion.

Presents a study that reported a magnetically induced resonant voltage overshoot circuit which has no time delay between prepulse and mainpulse nor a voltage reversal on the electrodes. Technology problems with prepulse-mainpulse technique; Reason that rail gaps are not suited to long life, high-repetition rate lasers; Advantage and disadvantages of the operational modes depending on the voltage polarities of the circuits.

We have constructed a scanning tunneling microscope for operation under UHV conditions (10-8 Pa). With this instrument topographic measurements can be made on metal and semiconductor surfaces by means of a scanning tip electrode, driven by piezoelectric ceramic elements. The maximum area covered ranges up to 4000×4000 Å2 with a resolution better than 10 Å laterally and 0.15 Å rms perpendicular to the plane. Because of its compact design, the scan unit is very insensitive to vibrations and has a response time down to 0.3 ms. This allows a high scan rate to be used. In order to minimize temperature effects, special attention is paid to the geometry of the construction and the materials used, resulting in a drift ≤4 Å/min along the surface and 0.5 Å/min perpendicular. [ABSTRACT FROM AUTHOR]

The material interface of a molecular beam epitaxy grown Al0.5Ga0.5As-GaAs heterostructure is investigated on a cross-sectional (110) cleavage plane using tunnel spectroscopy. The depleted n-type region and the electron confinement layer adjacent to the interface are identified with local current-voltage spectroscopy. The spatial width of these layers is close to 15 nm. The spectroscopy can be interpreted with the valence-band offset in the interface, and a value of 0.35 eV is found for this quantity. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to explore whether an electronic nose, Aetholab, is able to discriminate between infected versus non-infected wounds, based on headspace analyses from wound swabs., Methods: A total of 77 patients participated in this pilot study. Each wound was assessed for infection based on clinical judgment. Additionally, two wound swabs were taken, one for microbiological culture and one for measurement with Aetholab. Diagnostic properties with 95% confidence intervals (95%CIs) of Aetholab were calculated with clinical judgment and microbiological culture results as reference standards., Results: With clinical judgment as reference standard, Aetholab had a sensitivity of 91% (95%CI 76-98) and a specificity of 71% (95%CI 55-84). Diagnostic properties were somewhat lower when microbiological culture results were used as reference standard: sensitivity 81% (95%CI 64-91), specificity 63% (95%CI 46-77)., Conclusions: Aetholab seems a promising diagnostic tool for wound infection given the diagnostic properties presented in this pilot study. A larger study is needed to confirm our results., (Copyright © 2019 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Objectives: Lung cancer is a leading cause of mortality. Exhaled-breath analysis of volatile organic compounds (VOC's) might detect lung cancer early in the course of the disease, which may improve outcomes. Subtyping lung cancers could be helpful in further clinical decisions., Materials and Methods: In a prospective, multi-centre study, using 10 electronic nose devices, 144 subjects diagnosed with NSCLC and 146 healthy subjects, including subjects considered negative for NSCLC after investigation, breathed into the Aeonose™ (The eNose Company, Zutphen, Netherlands). Also, analyses into subtypes of NSCLC, such as adenocarcinoma (AC) and squamous cell carcinoma (SCC), and analyses of patients with small cell lung cancer (SCLC) were performed., Results: Choosing a cut-off point to predominantly rule out cancer resulted for NSCLC in a sensitivity of 94.4%, a specificity of 32.9%, a positive predictive value of 58.1%, a negative predictive value (NPV) of 85.7%, and an area under the curve (AUC) of 0.76. For AC sensitivity, PPV, NPV, and AUC were 81.5%, 56.4%, 79.5%, and 0.74, respectively, while for SCC these numbers were 80.8%, 45.7%, 93.0%, and 0.77, respectively. SCLC could be ruled out with a sensitivity of 88.9% and an NPV of 96.8% with an AUC of 0.86., Conclusion: Electronic nose technology with the Aeonose™ can play an important role in rapidly excluding lung cancer due to the high negative predictive value for various, but not all types of lung cancer. Patients showing positive breath tests should still be subjected to further diagnostic testing., (Copyright © 2018 Elsevier B.V. All rights reserved.)