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Background: The basis for qualification for venom immunotherapy (VIT) is the fulfilment of both the clinical and immunological criteria. Diagnostic tests that confirm the immunological criterion of an IgE-mediated sensitization include skin prick tests (SPT), intradermal tests (IDT), and serum specific IgE (sIgE) for the culprit venom. Objective: This study aimed to assess the usefulness of SPT as the immunological marker in the diagnosis of insect venom sensitization in children with history of systemic reaction (SR) to insect sting evaluated by means of I-IV-grades Mueller's scale. There are no such studies in children. Methods: This cross-sectional study sample consisted of 416 children aged 3–18 years (mean age 10.6 ± 3.8), 76% males, all with the history of a systemic reaction (SR) after a Hymenoptera sting (48% of grade III/IV according to Mueller scale), diagnosed between 1999 and 2019 in the tertiary referral centre. The standard diagnostic tests were used. Specificity, sensitivity, and positive and negative predictive values were computed to assess the diagnostic properties of the clinical tests to distinguish between mild and severe SR. To assess the relative value of an individual test in predicting the qualification to VIT we incorporated the Shapley value (SV). Results: Positive SPT results were found in up to no more than 3% of children; among them less than 1% had only positive SPT and were negative for sIgE and IDT. Approximately 85% of the children had detectable venom sIgE, followed by positive IDT (75%). Almost 70% of children had positive both sIgE and IDT results. In children with grade III/IV reaction, about 80% of children had positive results of both of these tests. sIgE and IDT had sensitivity >0.80, whereas SPT had high specificity (>0.97) in differentiating between mild and severe SR. Relative value of diagnostic tests in predicting qualification to VIT varied between venoms. Bee venom IDT had higher SV (0.052) than sIgE (0.041). In contrast, wasp venom sIgE had higher SV (0.075) than IDT (0.035). Conclusion: SPTs are not an useful immunological marker of venom sensitization in children, and eliminating SPT does not result in a loss of diagnostic accuracy. Limiting diagnostics to venom sIgE and IDT would shorten the procedure and reduce costs. Future studies are needed to determine if venom sIgE as the first line diagnostic test, with IDT added only if the venom sIgE is undetectable, is an optimal diagnostic process.

In Poland, independent evaluations under the auspices of the Institute of Hematology and Transfusion Medicine (IHTM) are mandated for any new device, assay, systems for screening samples from whole blood and plasma donors prior to implementation by Blood Transfusion Center (BTC). In last 5 years, two new systems were introduced to the market by Abbott GmbH, namely the Alinity s and the Alinity i. The evaluations performed for these two systems included the assessment of sensitivity, specificity and precision for each of the four mandatory serological screening markers in Poland: Hepatitis B Surface Antigen (HBsAg), Hepatitis C virus antibodies (Anti-HCV), HIV antibodies (anti-HIV) and Syphilis antibodies (anti-Treponema pallidum, anti-TP). Sensitivity was assessed by testing seroconversion panels, HBsAg international reference standard, well characterized local samples, and dilution panels. Specificity was assessed by testing routine donor samples. The results from Alinity i assays were compared to the results from Abbott ARCHITECT i2000SR and Ortho VITROS 3600 assays, while the results from Alinity s assays were compared to the results of ARCHITECT i2000SR assays. The evaluation of the Alinity s and Alinity i assays for sensitivity (100 %), specificity (99,92–100 %) and precision generated results that were as good as or better than generated by routinely used systems, were within acceptance criteria, and met all requirements for screening blood donor samples in accordance with Polish regulations. The specificity of the assays in routine use by BTCs, analyzed after approximately 150,000 donations on both systems, was comparable to the specificity observed during the evaluations at IHTM.

Acoustic agglomeration is a technique that leverages on sound waves to promote the collision of aerosol particulate matter, thus leading to the formation of larger particle agglomerates. In this study, this acoustics-driven phenomenon is demonstrated for its usefulness as an aerosol pre-conditioning method to significantly enhance the efficiency of filtration systems in particle treatment processes. Specifically, favorable changes in pressure drop across the filters are observed as a result of receiving less particle mass, for which filters are shown to be able to have their operational life extended remarkably by more than 50%. The involved ultrasonic aerosol agglomeration mechanisms are unveiled through numerical simulations, and the effects of residence time, sound pressure level, and initial particle number concentration on agglomeration performances are experimentally investigated. In addition, validations and measurements of filter pressure drop are obtained through a series of experiments. This study provides a comprehensive overview to the design and performance characterization of acoustics-agglomeration-enhanced filtration systems, which could potentially derive energy savings for fan power in ventilation systems and be scaled up for applications in industrial plants for reducing carbon emissions.

Closing the resource loop by transforming plastic waste into higher value products is an important step for changing from a linear to circular economy. Using a sequential pyrolysis and catalytic chemical vapour deposition process, plastics have been successfully converted into carbon nanotubes (CNTs). Pure low density polyethylene (LDPE), polypropylene (PP) and mixed plastics (MP) were used as raw materials in the two-stage process. In the first stage, the plastics were pyrolysed at 600 °C. In the second stage, the non-condensable gases were converted into multi-walled CNTs over a Ni-based catalyst at two different temperatures, 500 and 800 °C. The influence of plastic feedstock and synthesis temperature on the performance of plastic-derived CNTs as electrode materials in electrocatalysis was investigated. The CNTs were evaluated as electrode materials for their heterogeneous electron transfer rate using a redox probe, which showed improved electrochemical behaviour. For oxygen reduction reaction (ORR), CNTs produced at 500 °C demonstrated superior performance compared to those produced at 800 °C. Influence of feedstock on electrocatalytic ORR activity of the as synthesised CNTs was marginal. Temperature was the governing factor influencing the properties of CNTs due to annealing and oxidation of edge defects generated during synthesis at higher temperatures. Keywords: Carbon nanotubes, Electrodes, Waste to resources, Electrocatalysis, Oxygen reduction reaction, Electrochemistry