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Conventional manufacturing of microfluidic devices from glass substrates is a complex, multi-step process that involves different fabrication techniques and tools. Hence, it is time-consuming and expensive, in particular for the prototyping of microfluidic devices in low quantities. This article describes a laser-based process that enables the rapid manufacturing of enclosed micro-structures by laser micromachining and microwelding of two 1.1-mm-thick borosilicate glass plates. The fabrication process was carried out only with a picosecond laser (Trumpf TruMicro 5×50) that was used for: (a) the generation of microfluidic patterns on glass, (b) the drilling of inlet/outlet ports into the material, and (c) the bonding of two glass plates together in order to enclose the laser-generated microstructures. Using this manufacturing approach, a fully-functional microfluidic device can be fabricated in less than two hours. Initial fluid flow experiments proved that the laser-generated microstructures are completely sealed; thus, they show a potential use in many industrial and scientific areas. This includes geological and petroleum engineering research, where such microfluidic devices can be used to investigate single-phase and multi-phase flow of various fluids (such as brine, oil, and CO2) in porous media. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis (TB) is treatable with a high cure rate. In South Africa, 70% of pulmonary TB is microbiologically confirmed. Autopsy studies of HIV-positive people found 45.7% undiagnosed TB cases., Objectives: The primary objective investigated whether CRP and a differentiated white cell count (WCC) and ratios thereof are useful screening tools for TB., Method: This retrospective cross-sectional study included adult patients admitted to two tertiary hospitals in Bloemfontein with TB workups between April 2016 and September 2019. National Health Laboratory Service (NHLS) provided laboratory data. Tuberculosis Xpert ® MTB/RIF, Xpert ® MTB/RIF Ultra and TB culture were used as reference standard for TB diagnosis., Results: The study population comprised 1294 patients; 15.1% had TB, 56.0% were male and 63.1% HIV-positive. Patients with TB were younger ( p < 0.0001; 95% CI: -8;-3 years). In the total population, WCC had the highest area under the curve (0.59). White cell count ( p < 0.0001), neutrophils ( p = 0.0003) and lymphocytes ( p = 0.0394) were lower in TB patients, and CRP-WCC ratio (CWR) ( p = 0.0009) and CRP-lymphocyte ratio (CLR) ( p = 0.0386) higher. In HIV-positive patients, WCC ( p = 0.0003), neutrophils ( p = 0.002) and lymphocytes ( p = 0.0491) were lower in TB patients and CWR ( p = 0.0043) higher. No parameter reached the World Health Organization screening targets of 70% specificity with 90% sensitivity., Conclusion: Differentiated WCC and CRP are not useful in screening hospitalised patients for TB in our setting., Contribution: Our study guides future research to augment current screening and diagnostic algorithms for TB, specifically in advanced HIV disease., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article., (© 2023. The Authors.)

An error on the part of the authors in drafting resulted in Eq. (3) being incorrect in the published paper [Opt. Express25, 20612 (2017)10.1364/OE.25.020612]. We present a corrected version of the equation. It should be noted that this does not affect the presented results or conclusions of the paper.

For many blood-based diagnostic tests, including prophylactic drug analysis and malaria assays, red blood cells must be lysed effectively prior to their use in an analytical workflow. We report on a finger-actuated blood lysate preparation device, which utilises a previously reported acoustofluidic micromixer module. The integrated device includes a range of innovations from a sample interface, to the integration of blisters on a laser engraved surface and a large volume (130 μL) one-stroke manual pump which could be useful in other low-cost microfluidic-based point-of-care devices. The adaptability of the acoustic mixer is demonstrated on highly viscous fluids, including whole blood, with up to 65% percent volume fraction of red blood cells. Used in conjunction with a lysis buffer, the micromixer unit is also shown to lyse a finger-prick (approximately 20 μL) blood sample in 30 seconds and benchmarked across ten donor samples. Finally, we demonstrate the ease of use of the fully integrated device. Cheap, modular, but reliable, finger-actuated microfluidic functions could open up opportunities for the development of diagnostics with minimal resources.

We report systematic analysis and comparison of ps-laser microwelding of industry relevant Al6082 parts to SiO 2 and BK7. Parameter mapping of pulse energy and focal depth on the weld strength is presented. The welding process was found to be strongly dependent on the focal plane but has a large tolerance to variation in pulse energy. Accelerated lifetime tests by thermal cycling from -50° to +90°C are presented. Welds in Al6082-BK7 parts survive over the full temperature range where the ratio of thermal expansion coefficients is 3.4:1. Welds in Al6082-SiO 2 parts (ratio 47.1:1) survive only a limited temperature range.