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This work presents a unique approach to the design, fabrication, and characterization of paper-based origami robotic systems consisting of stackable pneumatic actuators. These paper-based actuators (PBAs) use materials with high elastic modulus-to-mass ratios, accordion-like structures, and direct coupling with pneumatic pressure for extension and bending. The study contributes to the scientific and engineering understanding of foldable components under applied pneumatic pressure by constructing stretchable and flexible structures with intrinsically nonstretchable materials. Experiments showed that a PBA possesses a power-to-mass ratio greater than 80 W/kg, which is more than four times that of human muscle. This work also illustrates the stackability and functionality of PBAs by two prototypes: a parallel manipulator and a legged locomotor. The manipulator consisting of an array of PBAs can bend in a specific direction with the corresponding actuator inflated. In addition, the stacked actuators in the manipulator can rotate in opposite directions to compensate for relative rotation at the ends of each actuator to work in parallel and manipulate the platform. The locomotor rotates the PBAs to apply and release contact between the feet and the ground. Furthermore, a numerical model developed in this work predicts the mechanical performance of these inflatable actuators as a function of dimensional specifications and folding patterns. Overall, we use stacked origami actuators to implement functionalities of manipulation, gripping, and locomotion as conventional robotic systems. Future origami robots made of paper-like materials may be suitable for single use in contaminated or unstructured environments or low-cost educational materials.

A noise-suppressing low-light image enhancement approach is proposed in this paper based on the extent of exposedness at each image pixel. To this end, a progressive, structure-aware exposedness estimation procedure is presented that quantifies local and global exposedness. These exposedness values are leveraged to produce a locally smooth pixel-level map that signifies the required degrees of enhancement at image pixels. This map is subsequently used in an enhancement function, which satisfies a few important properties, to generate the enhanced image. Before the enhancement, inherent noise in the low-light image is diminished employing a detail-preserving, low gradient magnitude suppression method. Subjective and quantitative analysis of results on a wide variety of natural and synthetically generated low-light images from standard databases using PSNR, iRSE, SSIM, and measures of perceptual quality, natural image statistics and brightness preservation suggests that our approach in general outperforms the state-of-the-art. Ablation studies and further experiments show the importance of a few components of our approach, and that our approach is computationally fast.

Selective detection and quantification of biomarkers related to human diseases are essential for preventive healthcare. Surface-enhanced Raman scattering (SERS) spectroscopy is a powerful analytical tool offering high sensitivity. However, the success of this promising analytical tool relies on the ability to effectively fabricate SERS substrate. Herein we have demonstrated a plasmonic paper-based flexible substrate (PPFS) for SERS sensing. In situ growth of silver nanostructures (AgNS) on the paper-based substrate was achieved by using a simple one-step silver mirror reaction (SMR). FESEM and TEM results depicts that the increasing silver ion content influences the morphology (growth of multifacets), as well as size of AgNS. Further, the PPFS substrate was tested with Rhodamine-6G (Rh-6G) dye and an attomole sensitivity with a LOD of 4.54 x 10-18 M was achieved. Further, two biomarkers, lactic acid (LA) and uric acid (UA) were detected on the PPFS substrate, with μM and pM sensitivity, having LOD values of 0.6 x 10-6 and 0.3 x 10-12 M respectively. Above detection levels for UA on PPFS is two orders better than reported values, whereas for LA it is comparable with reported substrates. Finally, UA, LA and their mixtures were tested on PPFS and results compared with commercial substrate. The performance of PPFS were found better in all cases, thus, multifaceted AgNS paper based PPFS offers the potential to be used as a biosensor for detection of various biomarkers from body fluids, responsible for the detection of the critical disease for preventive health care.

The design rules of winding configurations and stator-pole/rotor-tooth (SP/RT) number combinations of doubly-fed flux-switching permanent magnet (DF-FSPM) machines are investigated in this paper based on coil-EMF vectors. The relationships between the components of stator and rotor coil-EMF vector diagrams are unveiled at first, including the numbers of stator and rotor phases, and the numbers of stator and rotor spokes. Then, the SP/RT number combinations are derived considering feasible stator/rotor phase number combinations and different winding configurations. The SP/RT number combinations are optimized considering the winding factors, magnetic field harmonics, unbalanced magnetic forces and machine diameter. It is shown that both of the stator and rotor pitch factors increase when the SP and RT numbers get closer. Furthermore, the influence of winding configurations and SP/RT number combinations on electromagnetic performances of DF-FSPM machines are analyzed by finite-element method. Finally, the analysis results are validated by experiment.

In this work, we present for the first time, a simplified fabrication of a laminated paper-based analytical device (LPAD) with a free-mobile app, Palette Cam, for image analysis. A filter paper is cut in a rectangular shape (9 × 3 cm) and placed between a top laminating sheet with punched holes and a bottom laminating sheet. The holes allow accessibility of liquid on the paper. Thermal lamination is then employed to complete the fabrication of LPAD. Our simplified design reduces a tedious alignment of small pieces of paper to the holes. We demonstrated the LPAD with an analysis of salicylic acid in pharmaceutical products. Each 4 μL of ferric reagent and sample was dispensed on the LPAD. Smartphone was used to capture images. The RGB (red green blue) color intensity from the Palette Cam was converted into a logarithm color ratio. Our LPAD is simplified, cost-effective and able to be a portable device.

Purpose This study aimed to determine whether continual electronic patient-reported outcome (ePRO) measurements at home can capture the fluctuations in health-related quality of life (HRQOL) scores between visits. Methods We performed a randomized controlled trial to compare the scores obtained by standard practice (paper-based measurements in the hospital) to scores by continuous measurement of ePRO at home. Metastatic cancer patients were randomly assigned to either the paper-based ( n = 50) or the ePRO group ( n = 52). EQ-5D-5L and EORTC QLQ C-30 scores were obtained on 3 different chemotherapy days in the paper-based group. Meanwhile, scores were obtained on the chemotherapy day and on days 3, 7, 10, and 14 in the ePRO group during 2 cycles. The first hypothesis of our study was that both scores at the same time points would be equivalent despite different measurement frequency, place, or mode of measurement. The second hypothesis was that PRO score–adjusted time would be different between the groups. For equivalence, the endpoint was the mean EQ-5D-5L index value on the chemotherapy day before the outpatient treatment. Only if equivalence was shown, quality-adjusted life-days (QALDs) were considered using all the data. Results The adjusted mean difference in the EQ-5D-5L index was determined to be −0.013 (95% confidence interval [CI]: −0.049 to 0.022); the 95% CI did not exceed the equivalence margin. Similarly, the mean difference in global health status (2.28 [95% CI: −2.55 to 7.11]) also showed equivalence. However, the QALD by EQ-5D-5L was significantly lower in the ePRO group by 1.36 per 30 d (95% CI: −2.22 to −0.51; P = 0.0021). Conclusions Continual measurements of the HRQOL at home by ePRO may yield more detailed profiles of the HRQOL.

Background The screening of biological hazards, chemical contaminants and allergens in food products is a major concern of food industry since they can cause serious illnesses and even lead to death. Therefore, there is a significant interest in developing low-cost, robust, and rapid detection methods for food safety and quality analysis. Conventional methods provide accurate analytical characteristics, but require well-equipped laboratories, trained personnel, costly reagents, and complicated sample preparation procedures prior to the detection in order to obtain reliable results. Hence, they are not always ideal for on-site food surveillance. Scope and approach This paper discusses the fundamentals of microfluidic paper-based analytical devices (μPADs) and reviews the recent progress in their usage for screening biological hazards, harmful chemical residues, and allergens in food products to systematically evaluate the strengths and weaknesses of this technology. It then covers future trends and useful strategies that could be employed in μPADs design and fabrication procedures to address the critical challenges in equipment-free food analysis. Key findings and conclusions μPADs offer promising avenues to revolutionize food safety and quality analysis with merits of equipment-free sample preparation and detection at low-cost. Despite the advancement in the microfluidic technology, the manufacturing of user-friendly sample-to-answer μPADs still requires intensive research studies to be employed for robust and sensitive food safety and quality analysis.

Poly ( p-phenylene benzoisoxazole; PBO) paper is a potential raw material for use in honeycomb sandwich composites in the aerospace industry, which are able to sustain high temperatures exceeding 300°C. This work presents a wet-forming method of making PBO paper, consisting of PBO chopped fibers. The paper was impregnated with phenolic resin to simulate honeycomb wall material. The structure and mechanical and dynamic mechanical properties of the raw and impregnated paper were characterized. The performance of PBO paper was tested against p-aramid paper. The comparative results showed the tensile strength of PBO raw paper was 2.17 kN/m, which was slightly worse than p-aramid raw paper: 2.66 kN/m. After impregnation, the tensile strength of the PBO paper was 13.93 kN/m due to the increase in the number of bonding points—better than p-aramid paper: 7.99 kN/m. The tearing resistance value for PBO raw paper versus p-aramid raw paper was 3252 mN against 845 mN. The morphology of the torn samples in the impregnated paper revealed higher levels of PBO fiber pullout than p-aramid fiber, therefore the tearing resistance value was 6000 mN for PBO impregnated paper, which was again superior to p-aramid impregnated paper: 675 mN. The PBO paper also showed higher storage modulus than p-aramid paper after impregnation. Experimental studies showed that PBO paper could be used in load-bearing structures and in honeycomb components where high resistance to deformation and thermal stability is necessary.

Expansion of a primary spontaneous intracranial hemorrhage (PSICH) has become lately of increasing interest, especially after the emergence of its early predictors. However, these signs lacked sensitivity and specificity. The flood phenomenon, defined as a drastic increase in the size of a PSICH during the same magnetic resonance study, was first described in this paper based on the data of a university medical center in Lebanon. Moreover, further review of this data resulted in 205 studies with presumed diagnosis of primary spontaneous intracranial hemorrhage within the last 10 years, of which 29 exams showed typical predictors of hematoma expansion on computed tomography. The intended benefit of this observation is to draw the radiologists’ attention towards minimal variations in the volume of the hematoma between the two extreme sequences of the same MRI study, in order to detect inconspicuous flood phenomena—a direct sign of hematoma expansion.

Background Electronic health record (EHR) system has many advantages. However, the implementation of it is challenging in a limited resources. Alongside with the challenge related to big change that clinicians have to adapt with. This causes hospital around the world changes the patient documentation, from paper based health record to EHR system. Evaluation about EHR system implementation is a crucial things. One of her evaluation implementation can be seen through measuring EHR user satisfaction. Objective To determine physicians’ and nurses’ satisfaction in EHR implementation. Method This was a cross-sectional designed descriptive analytical research. There were 52 respondents consists of physicians and nurses who work in the out patient unit involved in the study. Data were collected using Electronic Health Record Nurse Satisfaction (EHRNS) developed by Sockolow et al. Result The mean of the effect of EHR in patient outcomes is equivalent to M = 3.9 ± 0.7 in nurses and M = 4.1 ± 0.8 in physicians. The effect of EHR usage on the patient's comfort is equivalent to M = 3.8 ± 0.5 in nurses and M = 3.7 ± 0.8 in doctors. EHR training is equivalent to M = 4.6 ± 0.6 in nurses and M = 4.3 ± 0.7 in doctors. There is no significance difference in satisfaction between nurses and doctors. Conclusion Overall, nurses and physicians were satisfied with some functions in EHR system. However, there are some functions that didn’t satisfy the users and need to be improved.

Purpose In flexible electronics applications, organic inks are mostly used for inkjet printing. Three-dimensional (3 D) printing technology has the advantages of low cost, high speed and good precision in modern electronic printing. The purpose of this study is to solve the high cost of traditional printing and the pollution emissions of organic ink. It is necessary to develop a water-based conductive ink that is easily degradable and can be 3 D printed. A nano-silver ink printed circuit pattern with high precision, high conductivity and good mechanical properties is a promising strategy. Design/methodology/approach The researched nano-silver conductive ink is mainly composed of silver nanoparticles and resin. The effect of adding methyl cellulose on the ink was also explored. A simple 3 D circuit pattern was printed on photographic paper. The line width, line length, line thickness and conductivity of the printed circuit were tested. The influence of sintering temperature and sintering time on pattern resistivity was studied. The relationship between circuit pattern bending performance and electrical conductivity is analyzed. Findings The experimental results show that the ink has the characteristics of low silver content and good environmental protection effect. The printing feasibility of 3 D printing circuit patterns on paper substrates was confirmed. The best printing temperature is 160°C–180°C, and the best sintering time is 30 min. The circuit pattern can be folded 120°, and the cycle is folded more than 60 times. The minimum resistivity of the circuit pattern is 6.07 µΩ·cm. Methyl cellulose can control the viscosity of the ink. The mechanical properties of the pattern have been improved. The printing method of 3 D printing can significantly reduce the sintering time and temperature of the conductive ink. These findings may provide innovation for the flexible electronics industry and pave the way for alternatives to cost-effective solutions. Originality/value In this study, direct ink writing technology was used to print circuit patterns on paper substrates. This process is simple and convenient and can control the thickness of the ink layer. The ink material is nonpolluting to the environment. Nano-silver ink has suitable viscosity and pH value. It can meet the requirements of pneumatic 3 D printers. The method has the characteristics of simple process, fast forming, low cost and high environmental friendliness.

Aβ42 is one of the most extensively studied blood and Cerebrospinal fluid (CSF) biomarkers for the diagnosis of symptomatic and prodromal Alzheimer’s disease (AD). Because of the heterogeneity and transient nature of Aβ42 oligomers (Aβ42Os), the development of technologies for dynamically detecting changes in the blood or CSF levels of Aβ42 monomers (Aβ42Ms) and Aβ42Os is essential for the accurate diagnosis of AD. The currently commonly used Aβ42 ELISA test kits usually mis-detected the elevated Aβ42Os, leading to incomplete analysis and underestimation of soluble Aβ42, resulting in a comprised performance in AD diagnosis. Herein, we developed a dual-target lateral flow immunoassay (dLFI) using anti-Aβ42 monoclonal antibodies 1F12 and 2C6 for the rapid and point-of-care detection of Aβ42Ms and Aβ42Os in blood samples within 30 min for AD diagnosis. By naked eye observation, the visual detection limit of Aβ42Ms or/and Aβ42Os in dLFI was 154 pg/mL. The test results for dLFI were similar to those observed in the enzyme-linked immunosorbent assay (ELISA). Therefore, this paper-based dLFI provides a practical and rapid method for the on-site detection of two biomarkers in blood or CSF samples without the need for additional expertise or equipment. Graphical Abstract

Paper-based fluorescence devices, with smartphone aids, bring considerable operation convenience for tetracycline (TC) sensing. Nevertheless, they must meet the challenge in real determination against complicated backgrounds. Considering that, we present a programmable-printing paper-based device and then apply it to TC determination for various natural samples. MoS2 NPs and Gmp/Eu-Cit are synthetized as composite probes. A static quenching process is found with MoS2 NP fluorescence at 430 nm, while significant magnification of Gmp/Eu-Cit emission is obtained at 617 nm, establishing a valuable ratiometric indicator. Remarkably, two-stage programmable printing maximizes the proposed sensing capability. A transitive device, containing a gradually changing amount of a certain probe, is prepared to sense TC. With a homemade smartphone application and 3D-printed measurement chamber, the corresponding signals are examined to explore optimal setups. These setups are automatically processed to prepare the final-version device, not requiring manual operations. Benefitting from this interesting feature, the proposed device gains many rewards in performances. It effectively senses TC in a wide range from 12.7 nM to 80 μM and simultaneously provides naked eye-legible signals and smartphone-based readouts with confident selectivity and stability. This device is consequently applied for various samples of soil, river water, milk, and serum and meets well with HPLC-MS and recovery tests.

Iron is an important micronutrient involved in several mechanisms in the human body and can be an important biomarker. In this work, a simple and disposable microfluidic paper-based analytical device (µPAD) was developed for the quantification of iron in urine samples. The detection was based on the colorimetric reaction between iron(II) and bathophenanthroline and the reduction of iron(III) to iron(II) with hydroxylamine. The developed µPAD enabled iron determination in the range 0.07–1.2 mg/L, with a limit of detection of 20 µg/L and a limit of quantification of 65 µg/L, thus suitable for the expected values in human urine. Additionally, targeting urine samples, the potential interference of the samples color was overcome by incorporating a sample blank assessment for absorbance subtraction. Stability studies revealed that the device was stable for 15 days prior to usage and that the formed colored product was stable for scanning up to 3 h. The accuracy of the developed device was established by analyzing urine samples (#26) with the developed µPAD and with the atomic absorption spectrometry method; the relative deviation between the two sets of results was below 9.5%. Graphical abstract: [Figure not available: see fulltext.]

Paper has been widely employed as cheap material for the development of a great number of sensors such as pregnancy tests, strips to measure blood sugar, and COVID-19 rapid tests. The need for new low-cost analytical devices is growing, and consequently the use of these platforms will be extended to different assays, both for the final consumer and within laboratories. This work describes a paper-based electrochemical sensing platform that uses a paper disc conveniently modified with recognition molecules and a screen-printed carbon electrode (SPCE) to achieve the detection of gluten in a deep eutectic solvent (DES). This is the first method coupling a paper biosensor based on aptamers and antibodies with the DES ethaline. Ethaline proved to be an excellent extraction medium allowing the determination of very low gluten concentrations. The biosensor is appropriate for the determination of gluten with a limit of detection (LOD) of 0.2 mg L−1 of sample; it can detect gluten extracted in DES with a dynamic range between 0.2 and 20 mg L−1 and an intra-assay coefficient of 10.69%. This approach can be of great interest for highly gluten-sensitive people, who suffer from ingestion of gluten quantities well below the legal limit, which is 20 parts per million in foods labeled gluten-free and for which highly sensitive devices are essential. Graphical abstract

The appearance and quick spread of the new severe acute respiratory syndrome coronavirus disease, COVID-19, brought major societal challenges. Importantly, suitable medical diagnosis procedures and smooth clinical management of the disease are an emergent need, which must be anchored on novel diagnostic methods and devices. Novel molecular diagnostic tools relying on nucleic acid amplification testing have emerged globally and are the current gold standard in COVID-19 diagnosis. However, the need for widespread testing methodologies for fast, effective testing in multiple epidemiological scenarios remains a crucial step in the fight against the COVID-19 pandemic. Biosensors have previously shown the potential for cost-effective and accessible diagnostics, finding applications in settings where conventional, laboratorial techniques may not be readily employed. Paper- and cellulose-based biosensors can be particularly relevant in pandemic times, for the renewability, possibility of mass production with sustainable methodologies, and safe environmental disposal. In this review, paper-based devices and platforms targeting SARS-CoV-2 are showcased and discussed, as a means to achieve quick and low-cost PoC diagnosis, including detection methodologies for viral genomic material, viral antigen detection, and serological antibody testing. Devices targeting inflammatory markers relevant for COVID-19 are also discussed, as fast, reliable bedside diagnostic tools for patient treatment and follow-up., The authors acknowledge funding through projects Eco2Covid (POCI-01-02B7-FEDER-068174) and TecniCov (POCI-01-02B7-FEDER-069745), co-funded by FEDER through COMPETE2020 and Lisboa2020. T.P., A.R.C. and A.C.M. acknowledge funding to National Foundation for Science and Technology, I.P., FCT, through their PhD grants, references DFA/BD/8606/2020, SFRH/BD/130107/2017 and SFRH/BD/115173/2016, respectively, info:eu-repo/semantics/publishedVersion

Colorimetric gas detectors have been widely applied in many fields such as environmental sciences, industrial hygiene, process control, forensic science and indoor air quality monitoring. They have a history of about 100 years and include devices such as gas detector tubes and paper-based gas detectors. The sensitivity and selectivity of the colorimetric gas detector are relatively high compared to other types of gas detectors such as semiconductor, catalytic combustion and electrochemical gas detectors. Detection of gas concentration can be performed by the naked eye in some colorimetric gas detectors. These methods do not require an electrical power source and are simple, so they are suitable for field operations. This review introduces the history and provides a general overview of the development in the research of colorimetric gas detectors. Recently, the sensitivity and selectivity of colorimetric gas detectors have improved. New materials such as enzymes or particles with a large surface area have been utilized to improve selectivity and sensitivity. Moreover, new gas detectors without toxic materials have been developed to reduce the environmental load. At present, there is a rapid development of IoT sensors in many industrial fields, which might extend the applications of colorimetric gas detectors in the near future.

The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of paper-based analytical device (PAD) for enabling quantitative analysis without the requirement for a micropipette, since the PAD features a large sample loading zone and a waste zone, enabling accurate volume control of a liquid sample. We initially employed a micropipette to evaluate the PAD and demonstrate the quantitative analysis of ascorbic acid (AA) and pH using different loading volumes. Finally, we determined the AA concentrations and pH values of commercially available beverages using disposable plastic droppers, and the obtained results were in good agreement with those obtained through conventional methods. This PAD format can therefore be used as a novel educational tool for conducting certain chemical analyses in remote learning environments.

Calls for the professionalising of homecare are often driven by a perceived gap in knowing ‘good care’. However, many training solutions are underpinned by a cognitivist notion of knowing as a rational process of making sense of sense. A different approach to knowing homecare is provided in this article, based on a very different set of assumptions on knowing and knowledge. Suggestions for researching homecare are provided, underpinned by the notion of sensory ways of knowing. These other ways of knowing ‘good care’ potentially reconfigure who and what are able to be attended to in the field of homecare.

This review article provides a comprehensive summary, discussion and perspective on recent research advances for a new kind of multifunctional fire‐resistant paper based on ultralong hydroxyapatite nanowires, including the synthesis, properties, and applications.

The spread of Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), resulting in a global pandemic with around four million deaths. Although there are a variety of nucleic acid-based tests for detecting SARS-CoV-2, these methods have a relatively high cost and require expensive supporting equipment. To overcome these limitations and improve the efficiency of SARS-CoV-2 diagnosis, we developed a microfluidic platform that collected serum by a pulling-force spinning top and paper-based microfluidic enzyme-linked immunosorbent assay (ELISA) for quantitative IgA/IgM/IgG measurements in an instrument-free way. We further validated the paper-based microfluidic ELISA analysis of SARS-CoV-2 receptor-binding domain (RBD)-specific IgA/IgM/IgG antibodies from human blood samples as a good measurement with higher sensitivity compared with traditional IgM/IgG detection (99.7% vs 95.6%) for early illness onset patients. In conclusion, we provide an alternative solution for the diagnosis of SARS-CoV-2 in a portable manner by this smart integration of pulling-force spinning top and paper-based microfluidic immunoassay.

Paper-based photodetectors have attracted extensive research interest owing to their environmentally friendly and highly deformable properties. Although perovskite crystals with outstanding optoelectronic properties have proved to be one of the most promising candidates for photodetectors, the development of paper-based photodetectors is hindered by the moisture absorptivity of paper and the instability of perovskite crystals in a humid atmosphere. In this study, we demonstrate a highly deformable and high-performance paper-based perovskite photodetector. The photodetector maintains its excellent performance even after exposure to a relative humidity of 60% for 120 h.

Tracer Study or alumni tracking is one of the methods used by several universities in Indonesia, to obtain input and feedback from alumni. Input and feedback obtained from alumni can be an improvement and development of the quality of the education system implemented at the university. Tracer studies are also useful in providing important information about the relationship between institutions and the world of work. The Tracer Study of the Indonesian Methodist University is still using a form (Paper Based), one of which is the D-III study program of Informatics Management and Computerized Accounting. The D-III study programs from previous years have produced many alumni who are ready to work, alumni data and the management system have not been saved to the database, so the stored data can be damaged, lost and it will take time to find alumni data. Therefore, a web-based tracer study information system is needed so that the system can be computerized. The website is built using the HTML, PHP, Bootstrap and MYSQL programming languages ​​as a data storage system or commonly called a database. The existence of this alumni tracer study website can facilitate the process of implementing the alumni tracer study. The system built is expected to improve and develop the quality of the current system.

Programmed cell death protein 1 (PD-1) is one of the coinhibitory checkpoints upon T cell activation, the abnormal expression of which severely threatens host immune modulatation for chronic infection. Thus, fast and sensitive monitoring of PD-1 is of vital importance for early diagnosis and cancer treatment. The current detection methods largely based on enzyme-linked immunosorbent assay (ELISA) require time-consuming incubation and complicated washing steps. Herein, we designed a simple and portable nanofiber paper (NFP)-based fluorescence "off-on" immunosensor for PD-1 rapid determination. Molybdenum disulfide (MoS2) nanosheets modified NFP (MoS2-NFP) was employed for adsorbing and immobilizing CdSe/ZnS quantum dots-antibody (QDs-Ab) complex to construct a ready-to-use fluorescent immunosensor. The fluorescent signal of QDs-Ab was initially quenched by MoS2 under the Forster resonance energy transfer (FRET) effect. When the PD-1 target was specifically captured onto NFP by immunization, the QDs-Ab-PD-1 complex was promptly desorbed from the MoS2-NFP surface, resulting in FRET impediment and fluorescence recovery. As an alternative quenching agent, graphene oxide (GO) served as a contrast to investigate NFP-based sensing performance. Owing to superior quenching and desorption efficiency, the MoS2-NFP-based fluorescence immunosensor exhibited nearly 2-fold lower detection limit (85.5 pg/mL) than GO-NFP-based sensor (151 pg/mL) for PD-1 monitoring. Excellent selectivity and satisfactory recovery in PD-1 mouse cell culture supernatant samples were confirmed as well. In addition, the comparable detectability of the MoS2-NFP-based immunosensor was accurately evaluated by a standard PD-1 mouse ELISA kit. This study displayed a simple, rapid, low-cost, and portable point-of-care PD-1 assay, indicating its broad application prospect toward clinical diagnoses.

A cellulosic fibre based well-being fragrance packet has been developed by Central Institute for Research on Cotton Technology (CIRCOT). Inside the packet, three layers of cotton nonwoven (gram per square meter 100) have been used as core material. Fragrance based natural essential oil (citronella oil) has been incorporated in the middle non-woven layer of the cotton. Volatile active species of the essential oil infused in the cotton non-woven slowly has been diffused through the upper and lower non-woven layers in the surrounding atmosphere through the pores of the paper based sheath material. As per feedback report, a fragrance released from the packet is satisfactory up to seven days in the 25–30 square feet area. Mosquito repellency of the well-being packet also has been examined by following the standard cone test method. It has been observed that the smell release from the pack is capable to repel mosquitoes (100%) up to five days after opening the pack. The intensity of the active ingredients of fragrance released from the packet with time has been measured by gas chromatography analysis. The engineered pack has lightweight, is biodegradable, delivers well-being fragrance and repels mosquitoes up to one week.

Rewritable paper is meaningful to the recyclable and sustainable utilization of environmental resources and thus has been extensively investigated for several decades. In this work, we demonstrated an efficient and convenient strategy to fabricate rewritable paper based on reversible hydrochromism of donor-acceptor Stenhouse adducts (DASAs). The kinetics and efficiency of isomerization could be well-controlled by adjusting the surrounding temperature and humidity. Monocolored rewritable paper was prepared by coating cyclic DASA·xH2O on the paper surface. Writing, printing, stamping and patterning were realized on the rewritable paper. The information could be controllably erased by treatment in a humid atmosphere. More importantly, the rewritable paper was upgraded to multicolored by combination of two DASA materials. The color of chirography was switched by controlling the writing speed.

COVID-19 first appeared in December of 2019 in Wuhan, China. Since then it has become a global pandemic. A robust and scalable diagnostics strategy is crucial for containing and monitoring the pandemic. RT-PCR is a known, reliable method for COVID-19 diagnostics which can differentiate between SARS-CoV-2 and other viruses. However, PCR is location dependent, time consuming and relatively expensive. Thus, there is a need for a more flexible method which may be produced in an off-the-shelf format and distributed more widely. Paper-based immunoassays can fulfill this function. Here we present the first steps towards a paper-based test which can differentiate between different between the Spike protein of various coronaviruses, SARS-CoV-1, SARS-CoV-2 and CoV-HKU1 with negligible cross reactivity for HCoV-OC43 and HCoV-229E in a single assay which takes less than 30 minutes. Furthermore, our test can distinguish between fractions of the same Spike protein. This is done by an altered assay design with four test line locations where each antigen builds a unique, identifiable binding pattern. The effect of several factors, such as running media, immunoprobe concentration and antigen interference is considered. We find that running media has a significant effect on the final binding pattern where human saliva provides results while human serum leads to the lowest signal quality.

Feedback is beneficial to students’ learning process and overall achievement, but one of the common complaints from students about college education is regarding feedback. So, this study aimed to examine whether digital written feedback positively influences students’ learning experience and attitude toward learning. Digital written feedback refers to feedback provided through a learning management system as handwritten feedback added to a scanned copy of the student’s paper-based assessment using a smart pad and smart pencil. The study surveyed a diverse set of college students’ (n = 175) perceptions regarding feedback satisfaction, learning satisfaction, the usefulness of digital written feedback, and perceived achievement via an online survey. A one-way analysis of variance found a significant difference between feedback satisfaction and learning satisfaction according to the feedback method. A multiple regression analysis indicated the satisfaction and perceived usefulness of digital written feedback predicted perceived achievement. From the students’ open responses regarding the benefits of digital written feedback, five themes emerged, namely usability, psychological relief, accessibility, self-regulation, and acceptance. The implications for digital written feedback are discussed.

The salivary glands are closely associated with stress conditions and the neuroendocrine system. The concentrations of these salivary biomarkers fluctuate with a person’s disease status. Until now, salivary diagnostics have been promising; however, the analytical tools for detecting salivary biomarkers have remained burdensome due to the lack of user-friendly and cost-effective equipment. In this study, we used a microfluidic starch-coated paper-based chip to isolate ɑ-amylase from human saliva. The concentration of ɑ-amylase on the head and tail sections of the paper-based chip was compared in the presence or absence of starch. We found that ɑ-amylase was highly concentrated only in the head section of the starch-coated paper-based chip through Western blotting (WB) and enzyme-linked immunosorbent assay (ELISA). We expect our designed paper-based chip will aid in α-amylase detection technologies using saliva and small amounts of other biofluids including blood, tears, pancreatic juice, and urine.