Enhancing Micro-Raman Spectroscopy: A Variable Spectral Resolution Instrument Using Zoom Lens Technology.

Raman spectroscopy is a powerful analytical technique based on the inelastic scattering of photons. Conventional macro-Raman spectrometers are suitable for mass analysis but often lack the spatial resolution required to accurately examine microscopic regions of interest. For this reason, the development of micro-Raman spectrometers has been driven forward. However, even with micro-Raman spectrometers, high resolution is required to gain better insight into materials that provide low-intensity Raman signals. Here, we show the development of a micro-Raman spectrometer with implemented zoom lens technology. We found that by replacing a second collimating mirror in the monochromator with a zoom lens, the spectral resolution could be continuously adjusted at different zoom factors, i.e., high resolution was achieved at a higher zoom factor and lower spectral resolution was achieved at a lower zoom factor. A quantitative analysis of a micro-Raman spectrometer was performed and the spectral resolution was analysed by FWHM using the Gaussian fit. Validation was also performed by comparing the results obtained with those of a high-grade laboratory Raman spectrometer. A quantitative analysis was also performed using the ANOVA method and by assessing the signal-to-noise ratio between the two systems.

Pneumonia With Empyema: A Rare Clinical Presentation of Bartonella henselae Infection in a 10-Year-Old Boy.

BACKGROUND: Cat-scratch disease is a common zoonosis in children. However, atypical clinical presentation of cat-scratch disease is less common, and lung involvement is particularly rare. The usual presentation of lung disease in bartonellosis includes other organ involvement and is more common in immunocompromised patients. CASE REPORT: We present a 10-year-old immunocompetent patient with pneumonia and inoculated empyema caused by Bartonella henselae, without any other organ involvement, which occurred 2 weeks after lymphadenopathy. The definite diagnosis was established using the polymerase chain reaction of the empyema obtained from thoracocentesis. The boy was treated with several antibiotics (ceftriaxone, azithromycin, amoxicillin with clavulanic acid, meropenem and vancomycin) and completely recovered after the 3-month follow-up period. CONCLUSIONS: This is a unique case of the difficult-to-treat pneumonia with inoculated empyema, caused by B. henselae, in an immunocompetent child, without any other organ involvement. The clinical course was favorable. A high level of clinical suspicion is mandatory for the diagnosis.

Broken Rotor Bar Detection Based on Steady-State Stray Flux Signals Using Triaxial Sensor with Random Positioning.

This paper investigates the detection of broken rotor bar in squirrel cage induction motors using a novel approach of randomly positioning a triaxial sensor over the motor surface. This study is conducted on two motors under laboratory conditions, where one motor is kept in a healthy state, and the other is subjected to a broken rotor bar (BRB) fault. The induced electromotive force of the triaxial coils, recorded over ten days with 100 measurements per day, is statistically analyzed. Normality tests and graphical interpretation methods are used to evaluate the data distribution. Parametric and non-parametric approaches are used to analyze the data. Both approaches show that the measurement method is valid and consistent over time and statistically distinguishes healthy motors from those with BRB defects when a reference or threshold value is specified. While the comparison between healthy motors shows a discrepancy, the quantitative analysis shows a smaller estimated difference in mean values between healthy motors than comparing healthy and BRB motors.