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1.
Small (Weinheim an der Bergstrasse, Germany) ; : e2206274, 2023.
Article in English | EMBASE | ID: covidwho-2173460

ABSTRACT

Precise detection involving droplets based on functional surfaces is promising for the parallelization and miniaturization of platforms and is significant in epidemic investigation, analyte recognition, environmental simulation, combinatorial chemistry, etc. However, a challenging and considerable task is obtaining mutually independent droplet arrays without cross-contamination and simultaneously avoiding droplet evaporation-caused quick reagent loss, inaccuracy, and failure. Herein, a strategy to generate mutually independent and hardly-volatile capsular droplet arrays using innovative mosaic patterned surfaces is developed. The evaporation suppression of the capsular droplet arrays is 1712 times higher than the naked droplet. The high evaporation suppression of the capsular droplet arrays on the surfaces is attributed to synergistic blocking of the upper oil and bottom mosaic gasproof layer. The scale-up of the capsular droplet arrays, the flexibility in shape, size, component (including aqueous, colloidal, acid, and alkali solutions), liquid volume, and the high-precision hazardous substance testing proves the concept's high compatibility and practicability. The mutually independent capsular droplet arrays with amazingly high evaporation suppression are essential for the new generation of high-performance open-surface microfluidic chips used in COVID-19 diagnosis and investigation, primary screening, in vitro enzyme reactions, environmental monitoring, nanomaterial synthesis, etc. Copyright © 2023 Wiley-VCH GmbH.

2.
Frontiers in Neuroscience ; 16 (no pagination), 2022.
Article in English | EMBASE | ID: covidwho-2163063

ABSTRACT

COVID-19 is a systemic disease involving multiple organs, and clinically, patients have symptoms of neurological damage to varying degrees. However, we do not have a clear understanding of the relationship between neurological manifestations and viral infection due to the limitations of current in vitro study models. Brain organoids, formed by the differentiation of stem cells under 3D culture conditions, can mimic the structure of tiny cell clusters with neurodevelopmental features in different patients. The paper reviewed the history of brain organoids development, the study of the mechanism of viral infection, the inflammatory response associated with neurological damage, the detection of antiviral drugs, and combined microarray technology to affirm the status of the brain organoid models in the study of COVID-19. In addition, our study continuously improved the model in combination with emerging technologies, to lay a theoretical foundation for clinical application and academic research. Copyright © 2022 Yu, Wang and Zheng.

3.
Trends Analyt Chem ; 157: 116814, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2096071

ABSTRACT

The Coronavirus disease 2019 (COVID-19) outbreak has urged the establishment of a global-wide rapid diagnostic system. Current widely-used tests for COVID-19 include nucleic acid assays, immunoassays, and radiological imaging. Immunoassays play an irreplaceable role in rapidly diagnosing COVID-19 and monitoring the patients for the assessment of their severity, risks of the immune storm, and prediction of treatment outcomes. Despite of the enormous needs for immunoassays, the widespread use of traditional immunoassay platforms is still limited by high cost and low automation, which are currently not suitable for point-of-care tests (POCTs). Microfluidic chips with the features of low consumption, high throughput, and integration, provide the potential to enable immunoassays for POCTs, especially in remote areas. Meanwhile, luminescence detection can be merged with immunoassays on microfluidic platforms for their good performance in quantification, sensitivity, and specificity. This review introduces both homogenous and heterogenous luminescence immunoassays with various microfluidic platforms. We also summarize the strengths and weaknesses of the categorized methods, highlighting their recent typical progress. Additionally, different microfluidic platforms are described for comparison. The latest advances in combining luminescence immunoassays with microfluidic platforms for POCTs of COVID-19 are further explained with antigens, antibodies, and related cytokines. Finally, challenges and future perspectives were discussed.

4.
129th ASEE Annual Conference and Exposition: Excellence Through Diversity, ASEE 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2045146

ABSTRACT

This paper describes a novel project-oriented system on chip (SoC) design course. The course is taught in the Computer Science and Engineering (CSE) Department at the University of Texas at Arlington and is offered as CSE 4356 System on Chip Design for computer engineering undergraduates, as CSE 5356 for computer engineering graduate students, and as EE 5315 for electrical engineering graduate students. It is taught as one course combining all numbers. All students are given the same lectures, course materials, assignments, and projects. Grading standards and expectations are the same for all students as well. The course in its current form was first offered in fall 2020 and was taught online due to COVID-19 restrictions. The course was offered again in fall 2021 in a traditional on-campus, in-person mode of delivery. Two seasoned educators, with more than eighty years of total teaching experience, combined to team teach the course. One also brought more than thirty years of industrial design experience to the course. SoC FPGA devices have been available for use by designers for more than 10 years and are widely used in applications that require both an embedded microcomputer and FPGA-based logic for real-time computationally-intense solutions. Such solutions require skills in C programming, HDL programming, bus topologies forming the bridge between FPGA fabric and the microprocessor space, Linux operating systems and virtualization, and kernel device driver development. The breadth of the skills that were conveyed to students necessitated a team teaching approach to leverage the diverse background of the instructors. With such a wide range of topics, one of the biggest challenges was developing a course that was approachable for a greatly varied population of students - a mix of Computer Engineering (CpE) and Electrical Engineering (EE) students at both the graduate and undergraduate level. Another, perhaps less obvious, challenge was the inherently application focus of the course, which presents challenges to many graduate students whose undergraduate degree lacked a robust hands-on design experience. Selection of an appropriate project was key to making the course effective and providing a fun learning experience for students. The projects were aligned to relevant industry applications, stressing complex modern intellectual property (IP) work flows, while still being approachable to students. The design of a universal asynchronous receiver transmitter (UART) IP module in 2020 and a serial peripheral interface (SPI) IP module in 2021 were chosen as the projects for the first two offerings of the course. The Terasic/Intel DE1-SoC development board and Intel Quartus Prime 18.1 design software were the technologies chosen for the course. The development board and basic test instruments were provided to each student in a take-home lab kit. The system on chip design course has proven to be a popular but challenging course for our undergraduate and graduate students in computer engineering and electrical engineering. The course has demonstrated that it is possible to successfully teach an advanced design-oriented course to students of varying majors, levels, educational backgrounds, and cultures. © American Society for Engineering Education, 2022.

5.
Micromachines (Basel) ; 13(10)2022 Sep 22.
Article in English | MEDLINE | ID: covidwho-2043865

ABSTRACT

The spread of microorganisms in the air, especially pathogenic microorganisms, seriously affects people's normal life. Therefore, the analysis and detection of airborne microorganisms is of great importance in environmental detection, disease prevention and biosafety. As an emerging technology with the advantages of integration, miniaturization and high efficiency, microfluidic chips are widely used in the detection of microorganisms in the environment, bringing development vitality to the detection of airborne microorganisms, and they have become a research highlight in the prevention and control of infectious diseases. Microfluidic chips can be used for the detection and analysis of bacteria, viruses and fungi in the air, mainly for the detection of Escherichia coli, Staphylococcus aureus, H1N1 virus, SARS-CoV-2 virus, Aspergillus niger, etc. The high sensitivity has great potential in practical detection. Here, we summarize the advances in the collection and detection of airborne microorganisms by microfluidic chips. The challenges and trends for the detection of airborne microorganisms by microfluidic chips was also discussed. These will support the role of microfluidic chips in the prevention and control of air pollution and major outbreaks.

6.
31st IEEE Microelectronics Design and Test Symposium, MDTS 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2018965

ABSTRACT

This work introduces a simple detector for SARS-CoV-2 (COVID-19) virus. The detector operates in a very simple mechanism. Peripheral circuits to represent the testing result are also simulated. The system can be designed and fabricated in a single integrated circuit (IC) chip. The response time analysis of the device shows the speed of detection of this device. This detector will be highly effective to detect the SARS-CoV-2 virus in the future. © 2022 IEEE.

7.
25th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2021 ; : 123-124, 2021.
Article in English | Scopus | ID: covidwho-2012354

ABSTRACT

We present a multiplexed, electronic enzyme-linked immunosorbent assay (E2LISA) microchip for direct electrical detection and quantitation of multiple biomarkers from a single microliter-scale drop of sample. Spatially distinct spots on the microchip, each containing an interdigitated microelectrode array, are coated with specific capture agents and used to bind different analytes. Enzyme-labeled probes are then used to convert this analyte binding to an electrical impedance signal via the amplified, localized deposition of silver on the nanostructured, catalytic surface of the chip prepared using gold nanoparticles. We use this microchip with a custom handheld, cellphone interfaced reader to detect COVID-19 biomarkers including antigen-specific antibodies and viral antigens. Further, we demonstrate the multiplexed measurement of distinct antibody responses in serum samples from convalescent COVID-19 patients versus uninfected vaccine recipients. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

8.
25th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2021 ; : 153-154, 2021.
Article in English | Scopus | ID: covidwho-2012239

ABSTRACT

Rapid, sensitive, quantitative and patient-friendly diagnostic tools have yet to be developed for COVID-19 continued monitoring at the point-of-care. Here, we present an instrument-free capillary microfluidic chip coupled to a lateral flow module that is compatible with a smartphone application for quantitative detection of SARS-CoV-2 from saliva samples. The microfluidic chip is fully autonomous, and performs aliquoting, sample metering, and sequential delivery of reagents. The limit of detection is 0.07 ng/mL for recombinant nucleocapsid protein in saliva. This rapid antigen test provides results in less than 1 hour, without sacrificing analytical sensitivity. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

9.
25th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2021 ; : 843-844, 2021.
Article in English | Scopus | ID: covidwho-2012237

ABSTRACT

Since the early reports of SARS-CoV-2 in Wuhan, China in the winter of 2019, the virus spread has resulted in the most socially-crippling pandemic of the last century. Here, we report the development of a rapid, molecular COVID-19 test utilizing for the first time a loop-mediated isothermal amplification (LAMP) assay on Lab-on-Printed Circuit Board (Lab-on-PCB) to exploit the established integration and up-scaling advantages the latter offers. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

10.
25th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2021 ; : 711-712, 2021.
Article in English | Scopus | ID: covidwho-2012173

ABSTRACT

The SARS-CoV-2 pandemic has elevated the development of novel diagnostic solutions, including rapid nucleic acid amplification tests (NAATs), to a global priority to meet the high demand for accurate, timely viral detection and diagnosis. However, ubiquitously implemented NAATs, such as polymerase chain reaction (PCR), consume hours of testing. We report a field-forward instrument capable of ultra-fast real-time PCR for amplification-based nucleic acid detection in a custom-designed microfluidic chip. Prudent selection and unconventional positioning of thermal cyclers relative to the microfluidic chip and a fluorescent detector permit ultra-fast simultaneous amplification and detection, with 40 cycles complete in under 10 minutes. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

11.
CLEO: Science and Innovations, S and I 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2012157

ABSTRACT

We present an on-chip optical biosensor for the detection of COVID-19. The subwavelength grating waveguide-based micro-ring resonator with high sensitivity and low limit of detection integrates with microfludic channel, which promises clinical utility in point-of-care diagnostic. © Optica Publishing Group 2022, © 2022 The Author(s)

12.
25th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2021 ; : 127-128, 2021.
Article in English | Scopus | ID: covidwho-2011604

ABSTRACT

We will present a microfluidic assay to detect SARS-CoV-2 RNA from nasopharyngeal swab samples. Our method leverages isotachophoresis (ITP) to integrate sample preparation, RT-LAMP, and CRISPR-based nucleic acid detection in an automatable chip. For the first time, we use ITP to purify, pre-concentrate and isothermally amplify target nucleic acids into a ~1 µL reaction volume on-chip. The device then transitions LAMP amplicons into an on-chip zone containing Cas12-gRNA complexes and reporter molecules to measure target-activated CRISPR activity. We will use our method to automatically detect COVID-19 from nasopharyngeal swab samples. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

13.
25th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2021 ; : 969-970, 2021.
Article in English | Scopus | ID: covidwho-2011590

ABSTRACT

Nucleic acid amplification detection is one of the most widely used molecular diagnostic techniques in recent years, which can rapidly and efficiently amplify the characteristic nucleotide sequences of pathogenic bacteria in the diagnosis of infectious diseases, it has been widely used in clinical diagnosis, disease screening and other fields. In this work, we report a micro-cavity digital PCR for rapid detection of pathogens on a silicon-based microfluidic chip. The device has the advantages of high flux, no pumping, rapid reaction, quantification and high sensitivity. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.

14.
CLEO: Science and Innovations, S and I 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2011478

ABSTRACT

We report a label free, rapid and reliable bio-sensor for SARS-CoV-2(COVID-19), consisting of Silicon-Nitride Double-micro-ring-resonator (DMRR) with surface functionalization. Minimum detected concentration of ~ 10 cp/µL and sensitivity of 743 nm/RIU were achieved. © Optica Publishing Group 2022, © 2022 The Authors.

15.
J Nutr Sci ; 11: e64, 2022.
Article in English | MEDLINE | ID: covidwho-1972473

ABSTRACT

Marketing influences consumers' dietary purchases. However, little is known about marketing environments in Supplemental Nutrition Assistance Program (SNAP)-authorised stores. The present study explored SNAP-authorised store marketing environments in Louisiana by rurality, store ownership and store type (n 42). Sampling methods were designed to include randomly selected stores in each geographic area of the state. The GroPromo was used to measure placement, promotion, and child-focused aspects of marketing strategies used for healthier (fruits and vegetables) and less healthy products (chips, candy, sugar-sweetened beverages, child-focused cereal) in medium- and high-prominence marketing areas. In using multivariate analysis of variance (MANOVA) (P < 0⋅05) for data analysis, variations in GroPromo scores were found among SNAP-authorised stores by rurality (P < 0⋅05) and store ownership (P < 0⋅001); no differences were found by store type (P > 0⋅05). Future research, practice and policy strategies are required to understand the influence of marketing environments on SNAP participants' dietary quality and to design responsive public health interventions.


Subject(s)
Food Assistance , Beverages , Commerce , Food Supply , Humans , Marketing , Poverty
16.
11th Mediterranean Conference on Embedded Computing, MECO 2022 ; 2022.
Article in English | Scopus | ID: covidwho-1948824

ABSTRACT

In this paper, we present hardware-software methodology to measure and calculate heart and respiratory rates by using single, low-cost microcontroller chip of limited computation and memory performances, as ATTINY85. Sensors and analog front-end are very simple, directly interfaced to microcontroller pins. Implemented time and frequency domain signal processing algorithms are optimized for low-bits, low-memory architectures and allow fast reading of rates, provide satisfactory accuracy, noise immunity and low power consumption. The same methodology can be used in similar applications to determine dominant spectral frequency of slow signal, from a smaller number of points. © 2022 IEEE.

17.
Omega ; 113: 102720, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1907615

ABSTRACT

Covid-19 has allowed us to study systemic disruptions that impact entire industries. This paper explores how disruptions start, propagate, and continue over time by examining the semiconductor chip shortage faced by the auto industry during the years following Covid-19 in 2020. First, we carried out a thematic analysis of 209 pertinent newspaper articles. The analysis resulted in a thematic model of such disruptions with the interplay of various factors leading to the prolonged disruption to the auto sector. Second, we present the results from a stylized supply chain planning model run at different times to show how disruptions propagate to the auto and other sectors, causing systemic shortages. Overall, we contribute to the supply chain risk literature by focusing on system disruptions impacting entire industries versus normal disruptions affecting a particular company's supply chain.

18.
Acs Photonics ; 9(5):1513-1521, 2022.
Article in English | Web of Science | ID: covidwho-1895566

ABSTRACT

The COVID-19 pandemic has generated great interest in ultraviolet (UV) disinfection, particularly for air disinfection. Although UV disinfection was discovered close to 90 years ago, only very recently has it reached the consumer market and achieved much acceptance from the public, starting in the 2000s. The current UV light source of choice has been almost exclusively a low-pressure mercury vapor discharge lamp. Today, however, with emerging deep-UV (DUV) chip-scale technologies, there has been a significant advancement, along with ever-increasing interest, in the development and deployment of disinfection systems that employ compact devices that emit in the deep-UV spectral band (200- 280 nm), including UV light-emitting diodes (LEDs) and cathodoluminescent (CL) chips. This perspective looks into competing UV technologies (including mercury lamps and excimer lamps as benchmarks) on their optical merits and demerits and discusses the emerging chip-scale technologies of DUV electroluminescent and cathodoluminescent devices, comparing them against the benchmarks and providing an overview of the challenges and prospects. The accelerating progress in chip-scale solutions for deep-UV light sources promises a bright future in UV disinfection.

19.
15th IEEE International Conference on Nano/Molecular Medicine and Engineering, NANOMED 2021 ; 2021-November:23-27, 2021.
Article in English | Scopus | ID: covidwho-1874332

ABSTRACT

The current impact of COVID-19 on global health and the economy is enormous. Considering pandemic severity, there is an urgent need to develop a smart biosensor that can provide early detection of SARS-CoV-2 viruses with robust and reliable results. In this work, we have systematically developed a plasmonic-based biosensor chip for the early detection of the COVID-19 virus by providing fast and reliable results. The label-free plasmonic sensor utilizes light and detects the resonance oscillation of surface-bound free conduction electrons in the presence of the target analyte biomarker (virus), resulting in binding and affinity incidents at the surface of plasmonic gold (Au) material, causing a shift in the resonance wavelength. The results show the ability of biosensor to exhibit an increased shift in the resonance wavelength upon binding of the COVID-19 virus because of the change in the optical property, i.e., the refractive index of the medium in the vicinity of the Au film. This study further demonstrated the fabrication and performance optimization of the plasmonic biosensor for the potential point-of-care testing device. © 2021 IEEE.

20.
Electrochimica Acta ; 422, 2022.
Article in English | Scopus | ID: covidwho-1873023

ABSTRACT

We present an open source, fully wireless potentiostat (the “NanoStat”) for applications in electrochemistry, sensing, biomedical diagnostics, and nanotechnology, based on only 2 integrated circuit chips: A digital microcontroller with integrated on board WiFi and file/web server hardware/software, and an analog front end. This versatile platform is fully capable of all modern electrochemisty assays, including cyclic voltammetry, square wave voltammetry, chronoamperometry, and normal pulse voltammetry. The user interface is a web browser connected over http. All the code (firmware, HTML5, JavaScript) is hosted by the NanoStat itself without the need for any additional software. The total size is 4×40×20 mm and battery operation for 6 h is demonstrated, possible to extend to weeks or months in sleep mode. We anticipate that the applications of this could be very broad, from biomedical sensing in the clinic, to remote monitoring of unattended “motes”, to even possibly sensing aerial pathogens such as COVID in large public spaces without the need for anything other than a web browser for remote monitoring from anywhere in the world. Finally, we propose to use this software suite as a basis (kernel) of a fully open source, general purpose, web based electrochemistry software suite, ed from the hardware, which we call “OpenEChem”. © 2022

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