Performance of Rapid Antigen Tests for COVID-19 Diagnosis: A Systematic Review and Meta-Analysis

The identification of viral RNA using reverse transcription quantitative polymerase chain reaction (RT-qPCR) is the gold standard for identifying an infection caused by SARS-CoV-2. The limitations of RT-qPCR such as requirement of expensive instruments, trained staff and laboratory facilities led to development of rapid antigen tests (RATs). The performance of RATs has been widely evaluated and found to be varied in different settings. The present systematic review aims to evaluate the pooled sensitivity and specificity of the commercially available RATs. This review was registered on PROSPERO (registration number: CRD42021278105). Literature search was performed through PubMed, Embase and Cochrane COVID-19 Study Register to search studies published up to 26 August 2021. The overall pooled sensitivity and specificity of RATs and subgroup analyses were calculated. Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) was used to assess the risk of bias in each study. The overall pooled sensitivity and specificity of RATs were 70% (95% CI: 69–71) and 98% (95% CI: 98–98), respectively. In subgroup analyses, nasal swabs showed the highest sensitivity of 83% (95% CI: 80–86) followed by nasopharyngeal swabs 71% (95% CI: 70–72), throat swabs 69% (95% CI: 63–75) and saliva 68% (95% CI: 59–77). Samples from symptomatic patients showed a higher sensitivity of 82% (95% CI: 82–82) as compared to asymptomatic patients at 68% (95% CI: 65–71), while a cycle threshold (Ct) value ≤25 showed a higher sensitivity of 96% (95% CI: 95–97) as compared to higher Ct value. Although the sensitivity of RATs needs to be enhanced, it may still be a viable option in places where laboratory facilities are lacking for diagnostic purposes in the early phase of disease.

Improvement of field-deployable metagenomic virus detection by a simple pretreatment method.

As both the current COVID-19 pandemic and earlier pandemics have shown, animals are the source for some of the deadliest viral pathogens, which can spread to humans. Therefore, early detection at the point of incidence is crucial to both prevent and understand the threats posed to human health from pathogens in animal reservoirs. Often, the exact genetic nature of these zoonotic pathogens is unknown and advanced laboratory facilities do not exist in most field settings and therefore the development of methods for unbiased metagenomic and point of incidence detection is crucial in order to identify novel viral pathogens in animals with zoonotic and pandemic potential. Here we addressed some of these issues by developing a metagenomic Nanopore next-generation sequencing (mNGS) method for nucleic acids extracted from clinical samples from patients with SARS-CoV-2. To reduce the non-RNA viral genetic components in the samples, we used DNase pretreatment in a syringe followed by filtration and found that these pretreatments increased the number of SARS-CoV2 reads by > 500-fold compared with no pretreatment. The simple protocol, described here, allows for fast (within 6 hours) metagenomic detection of RNA viruses in biological samples exemplified by SARS-CoV-2 detection in clinical throat swabs. This method could also be applied in field settings for point of incidence detection of virus pathogens, thus eliminating the need for transport of infectious samples, cold storage and a specialized laboratory.

A versatile active learning workflow for optimization of genetic and metabolic networks

The study, engineering and application of biological networks require practical and efficient approaches. Current optimization efforts of these systems are often limited by wet lab labor and cost, as well as the lack of convenient, easily adoptable computational tools. Aimed at democratization and standardization, we describe METIS, a modular and versatile active machine learning workflow with a simple online interface for the optimization of biological target functions with minimal experimental datasets. We demonstrate our workflow for various applications, from simple to complex gene circuits and metabolic networks, including several cell-free transcription and translation systems, a LacI-based multi-level controller and a 27-variable synthetic CO2-fixation cycle (CETCH cycle). Using METIS, we could improve above systems between one and two orders of magnitude compared to their original setup with minimal experimental efforts. For the CETCH cycle, we explored the combinatorial space of ~1025 conditions with only 1,000 experiments to yield the most efficient CO2-fixation cascade described to date. Beyond optimization, our workflow also quantifies the relative importance of individual factors to the performance of a system. This allows to identify so far unknown interactions and bottlenecks in complex systems, which paves the way for their hypothesis-driven improvement, which we demonstrate for the LacI multi-level controller that we were able to improve by 100-fold after having identified resource competition as limiting factor. Overall, our workflow opens the way for convenient optimization and prototyping of genetic and metabolic networks with customizable adjustments according to user experience, experimental setup, and laboratory facilities.

Laboratory characterisations and intercomparison sounding test of dual thermistor radiosondes for radiation correction

A dual thermistor radiosonde (DTR) comprising two (white and black) sensors with different emissivities was developed to correct the effects of solar radiation on temperature sensors based on in-situ radiation measurements. Herein, the DTR performance is characterised in terms of the uncertainty via a series of ground-based facilities and an intercomparison sounding test. The DTR characterisation procedure using laboratory facilities is as follows: individually calibrate the temperature of the thermistors in a climate chamber; test the effect of temperature on the resistance reading using radiosonde boards in the climate chamber; individually perform radiation tests on thermistors; and perform parameterisation of the radiation measurement and correction formulas using an upper air simulator with varying temperature, pressure and ventilation speed. These results are combined and applied to the DTR sounding test conducted in July, 2021. Thereafter, the effective irradiance is measured using the temperature difference between the white and black sensors of the DTR. The measured irradiance is then used for the radiation correction of the DTR white sensor. The radiation-corrected temperature of the DTR is mostly consistent with that of a commercial radiosonde (Vaisala, RS41) within the expanded uncertainty (~0.35 ℃) of the DTR at the coverage factor k = 2. Furthermore, the components contributing to the uncertainty of the radiation measurement and correction are analysed. The DTR methodology can improve the accuracy of temperature measurement in the upper air within the framework of the traceability to the International System of Units.

Prefabricated Plug-and-Play Unitized Façade System for Deep Retrofitting: The RenoZEB Case Study

The retrofitting of the existing building stock is one of the most important goals to be pursued to meet European targets. In this context, the RenoZEB project has developed a modular methodology for the deep retrofitting of buildings, which is enabled by a prefabricated plug-and-play façade that integrates different on-market technologies to achieve nZEB standards. This article reports on the activities conducted in the study and design of the RenoZEB prefabricated envelope system, providing insights on the tests conducted and the results achieved for the façade system, with a specific focus on the use of technology laboratory facilities for real-environment validation, which revealed the system to be in line with the project objectives.

Zebrafish Beyond the Bench: The ‘Plataforma Zebrafish Open Doors’ Programme

The Butantan Institute is a pioneering Brazilian health sciences institution, which also houses a large science park with museums that contribute to ongoing science education for schools and the wider community. In recent years, as part of Butantan Institute’s Plataforma Zebrafish™, zebrafish embryos have been used for the dissemination of scientific knowledge during on-site events and as part of outreach campaigns to non-scientific audiences, mostly children. The aim of this work is mainly to demystify the activities of the scientific researcher, highlight the role of science in the furthering of knowledge, and increase public interest and confidence in science. In this article, the Institute’s ‘Plataforma Zebrafish Open Doors’ programme is described, which offered guided tours of the laboratory facilities. The tours gave visitors the opportunity to observe zebrafish research and embryo development, and to use the knowledge gained from this experience as a framework for understanding fundamental ethical issues. During the 2-day event, around 800 visitors (most of them school-age children) attended. Together with the guided tours, our experience of outreach offered meaningful opportunities to bring children and members of the public closer to science and ‘real-life’ scientists, hopefully inspiring and encouraging the next generation of scientists. It also gave the scientists an opportunity to engage more closely with wider society. We believe that these activities also substantially contribute to the wider dissemination of relevant experimental results that have been obtained with public funding and that impact society in general.

Android Based Animation Video Using Millealab Virtual Reality Application for Elementary School

Innovation in education is necessary for teachers and students to follow the learning process because of the limited laboratory facilities in elementary schools; science learning is done. This study aims to analyze student acceptance and understanding concept in using android-based animated videos on Millealab virtual reality in grade V elementary school. The research method process is carried out in several stages, starting from expert testing conducted on three media experts, three subject matter experts, and three teachers from 3 different schools. Test the use of virtual reality video with a sample size of 65 students. Collecting data using a Likert scale questionnaire 1 to 5, and treatment in descriptive analysis. Testing the acceptance of virtual reality videos to students showed that students received virtual reality video media during the learning process. The application of virtual reality (VR) technology in science learning in elementary schools can improve conceptual understanding so that student acceptance of VR is excellent and teachers also feel helped by using VR media to support the learning process. VR technology is better than AR because it is more comprehensive and easier to use by teachers and students.

A Simple Brushless Motor and Propeller Test Stand for Experiment from Home

A brushless motor and propeller test stand is used to test brushless motors and propellers. This testing instrument is still only available in research laboratories. Students and researchers are unable to use laboratory facilities because of the Covid-19 epidemic, thus students must be able to do tests independently from home. Purchasing this testing instrument would be too expensive for students. It is essential to construct a brushless motor and propeller testing instrument at home using simple components that are easy to get on the marketplace. The design concept reads force data using a loadcell sensor and an HX711 driver, and current and voltage data with an INA 219 sensor. The brushless motor’s rotational speed is controlled by a potentiometer. Force, current, voltage, and power are all examples of test results data. A 16×2 LCD is used to show data immediately. Data is also transmitted via a USB connection to a computer device for storage or additional analysis. This study proposes a simple brushless motor and propeller test stand that can measure forces from 0 gf to 1000 gf with an error rate of 0.72 %. The power that can be read ranges from 0 mW to 18960 mW, with a 0.59 % error rate.

Cluster Analysis of Russian Universities Based on the Dynamics of Their Performance Indicators

The article presents the results of a study, the aim of which is to investigate the dynamics of the development of Russian higher education institutions based on an analysis of their performance indicators. The sample includes 535 universities from 80 constituent entities of the Russian Federation. It presents the results of the clustering of universities on the basis of changes in indicators of six variables characterizing the key areas of activity of universities for the period from 2013/2014 to 2017/2018 academic years. The characteristics of each cluster are described, an inter-cluster comparison of quantitative indicators of the activities of universities is presented.As a result of the calculations of the average annual growth rates of six key indicators characterizing the activities of universities, fve clusters were identifed that differ in their development trajectories. Thus, the universities that belong to Cluster 1 over a fve-year period retained or improved their positions in the main areas of educational activity and managed to maintain income growth at an average level.However, their indicators in such areas as international and research activities, as well as infrastructure development (provision of educational and laboratory facilities) have decreased. In universities from clusters 2 and 3, all performance indicators changed in a fairly balanced way. At the same time, the indicator of an increase in the internationalization of the students’ body was signifcantly higher in Cluster 2, while educational organizations from Cluster 3 showed a signifcant increase in the publication activity of academic staff.The results of the activities of universities in Cluster 4 were positive in all considered areas. This cluster had the highest average annual growth rates in the average Unifed State Exam (USE) score and publication activity of the academic staff. Educational organizations from Cluster 5, on the one hand, achieved the best results in attracting foreign students, increasing the proftability of their activities and the provision of teaching and laboratory facilities but, on the other hand, their average annual growth rate of the average USE score has signifcantly decreased.The study represents one of the frst attempts to cluster Russian universities based on the analysis of changes in their performance indicators. Previous studies on the clustering of universities were mainly based on the analysis of one-time indicators. The approach proposed by the author makes it possible to compare indicators of the dynamics of development of higher educational institutions of different size and scope. Further research in this area could be aimed at analyzing a larger number of performance indicators of universities and studying in detail their strategies for a deeper understanding of the reasons for the differences in their effectiveness.