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Excessive emissions of heavy metals not only cause environmental pollution but also pose a direct threat to human health. Therefore, rapid and accurate detection of heavy metals in the environment is of great significance. Herein, we propose a method based on laser-induced breakdown spectroscopy (LIBS) combined with filter paper modified with bovine serum albumin-protected gold nanoclusters (LIBS-FP-AuNCs) for the rapid and sensitive detection of Cr3+ and Mn2+. The filter paper modified with AuNCs was used to selectively enrich Cr3+ and Mn2+. Combined with the multi-element detection capability of LIBS, this method achieved the simultaneous rapid detection of Cr3+ and Mn2+. Both elements showed linear ranges for concentrations of 10–1000 μg L−1, with limits of detection of 7.5 and 9.0 μg L−1 for Cr3+ and Mn2+, respectively. This method was successfully applied to the determination of Cr3+ and Mn2+ in real water samples, with satisfactory recoveries ranging from 94.6% to 105.1%. This method has potential application in the analysis of heavy metal pollution. [ABSTRACT FROM AUTHOR]

The advent of digital technology has revolutionized numerous aspects of modern life, including the field of assessment and testing. However, paper tests, despite their seemingly archaic nature, continue to hold a prominent position in various assessment domains. The accessibility, familiarity, security, cost-effectiveness, and versatility of paper tests collectively contribute to their continued prominence. Hence, numerous educational institutions responsible for conducting examinations involving a substantial number of candidates continue to rely on paper tests. Consequently, there arises a demand for the possibility of automated assessment of these tests, aiming to alleviate the burden on teaching staff, enhance objectivity in evaluation, and expedite the delivery of test results. Therefore, diverse software systems have been developed, showcasing the capability to automatically score specific question types. Thus, it becomes imperative to categorize related question types systematically, thereby facilitating a preliminary classification based on the content and format of the questions. This classification serves the purpose of enabling effective comparison among existing software solutions. In this research paper, we present the implementation of such a software system using artificial intelligence techniques, progressively expanding its capabilities to evaluate increasingly complex question types, with the ultimate objective of achieving a comprehensive evaluation of all question types encountered in paper-based tests. The system detailed above demonstrated a recognition success rate of 99.89% on a curated dataset consisting of 734,825 multiple-choice answers. For the matching type, it achieved a recognition success rate of 99.91% on 86,450 answers. In the case of short answer type, the system achieved a recognition success rate of 95.40% on 129,675 answers. [ABSTRACT FROM AUTHOR]

Excessive emissions of heavy metals not only cause environmental pollution but also pose a direct threat to human health. Therefore, rapid and accurate detection of heavy metals in the environment is of great significance. Herein, we propose a method based on laser-induced breakdown spectroscopy (LIBS) combined with filter paper modified with bovine serum albumin-protected gold nanoclusters (LIBS-FP-AuNCs) for the rapid and sensitive detection of Cr3+ and Mn2+. The filter paper modified with AuNCs was used to selectively enrich Cr3+ and Mn2+. Combined with the multi-element detection capability of LIBS, this method achieved the simultaneous rapid detection of Cr3+ and Mn2+. Both elements showed linear ranges for concentrations of 10–1000 μg L−1, with limits of detection of 7.5 and 9.0 μg L−1 for Cr3+ and Mn2+, respectively. This method was successfully applied to the determination of Cr3+ and Mn2+ in real water samples, with satisfactory recoveries ranging from 94.6% to 105.1%. This method has potential application in the analysis of heavy metal pollution.

Critical bleeding causes over 2 million deaths a year. Early hypofibrinogenemia is a strong predictor of mortality in critically bleeding patients. The early replenishment of fibrinogen can significantly improve outcomes. However, over replenishment can also be dangerous. Furthermore, there is no rapid, cheap, hand-held diagnostic that can aid critically bleeding patients in fibrinogen replacement therapy. In this study, we have developed a hand-held paper diagnostic that measures plasma fibrinogen concentrations. The diagnostic has the potential to be used as a point of care device both inside and outside of hospital settings. It can vastly reduce the time to treatment for fibrinogen replacement therapy. The diagnostic is a two-step process. First, thrombin and plasma are added onto horizontially-orientated paper strips where the fibrinogen is converted into fibrin, drastically increasing the plasma's hydrophobicity. Second, an aqueous blue dye is pipetted onto the strips and allowed to wick through the fibrin. The distance the blue dye wicks through the strip correlates precisely to the fibrinogen concentration. The diagnostic can provide results within a minute. It can distinguish low fibrinogen concentrations (ie. <2 g/L) from normal fibrinogen concentrations. It shows remarkable reproducibility between healthy individuals. It is unaffected by common blood conditions such as acidosis, blood alcohol, severe hypertriglyceridemia, severe haemolysis and warfarin administration. Finally, it is unaffected by humidity and can withstand cold temperatures. Image 1 • We have developed a new hand-held, paper-based blood diagnostic which can measure fibrinogen concentrations. • Testing is completed within 1 minute and needs only 3 μL of plasma – making it ideal for diagnosing hypofibrinogenemia. • The test can withstand acidosis, alcohol use, warfarin use, severe haemolysis and severe hypertriglyceridemia. • The test can also withstand a wide range of temperatures and humidities making it suitable for outdoor use. • The test has the potential to revolutionise point of care testing and save two million lives each year. [ABSTRACT FROM AUTHOR]

Abstract A highly selective and sensitive acridine-based colorimetric sensor 2-((7-chloro-2-methoxybenzo[b][1,5]naphthyridin-10-yl)amino)phenol (NAP) was developed for detection of Cu2+ ions both in aqueous solution and on test papers. Sensor NAP responses to Cu2+ ions by changing its color from yellow to pink, which could be easily observed by the naked eyes. Furthermore, the mechanism of the binding model of NAP -Cu2+ complex was investigated by 1H NMR, HRMS analysis, and DFT calculations. Graphical abstract The first acridine derivative used as a colorimetric sensor for Cu2+ detection was reported with a color change from yellow to pink observed by naked-eyes. Image 1 [ABSTRACT FROM AUTHOR]

Dyslexia is a type of Specific Learning Disability (SLD) that affects the educational development of a student, as it is the reason of difficulties not only in writing or reading but also in other disciplines like Mathematics. Research has proven that Information and Communication Technologies (ICT) can have a positive effect to the educational development of a dyslexic student. In this paper, twenty 6 th -grade primary-school students were observed while using computers during exams - ten with Dyslexia and ten with no SLDs. All students were called to solve a digital test and a paper test that were including some basic mathematic operations. The researcher recorded and examined the differences between the results from the two tests. Descriptive and deductive statistical analysis showed that students had better results when examined via a computer compared to a traditional written examination. [ABSTRACT FROM AUTHOR]

Abstract: Paper-based SERS active substrates were prepared adsorbing spherical and star-shaped gold nanoparticles on a standard filter paper support. Besides the deposition conditions, morphological parameters of the particles were found to strongly affect the enhancer properties of the substrates. The developed substrate was tested regarding surface homogeneity as well as in the quantitative analysis of malachite green, – a well documented Raman reporter dye – and proved to be capable also to detect the oxidation products of apomorphine, a well-known drug molecule used in Parkinson's disease. This material is simple to prepare, easy to handle and dispose and as such it could be a perfect target for further development of a new family of mass-produced, cheap solid SERS substrates. [Copyright &y& Elsevier]

A proof of concept for using paper test as a suitable method in the production of monoclonal antibodies (MAbs) is reported. The paper test which detects antibodies against porcine circovirus type 2 (PCV2) using colloidal gold-labelled capsid protein as the antigen probe was applied exclusively in the screening of anti-PCV2 MAbs. It allowed the detection of 118 single cell clones within 30 min using naked eyes. MAbs with specific binding to authentic epitopes on the virus were selected using a blocking strategy in which the antibody was pre-incubated with PCV2 viral sample before applying to the test paper. Five hybridomas secreting MAbs against the capsid protein were obtained, with only three of them capable of binding to PCV2. The results were validated and confirmed using enzyme-linked immunosorbent assay and immunofluorescence assay. The paper test is simple, rapid, and independent on professional technicians and proves to be an excellent approach for the screening of MAbs against specific targets., (Copyright© by the Polish Academy of Sciences.)