scholarly journals Use cases for COVID-19 screening and surveillance with rapid antigen-detecting tests: a systematic review

2021 ◽  
Author(s):  
Apoorva Anand ◽  
Jacob Bigio ◽  
Emily MacLean ◽  
Talya Underwood ◽  
Nitika Pant Pai ◽  
...  
Keyword(s):  
Systematic Review ◽  
Real World ◽  
Large Scale ◽  
Low Cost ◽  
Risk Of Bias ◽  
Use Cases ◽  
Global Alliance ◽  
Prevalence Survey ◽  
Screening And Surveillance ◽  
Wide Range

Introduction: Testing is critical to controlling the COVID-19 pandemic. Antigen-detecting rapid diagnostic tests (Ag-RDTs) that can be used at the point of care have the potential to increase access to COVID 19 testing, particularly in settings with limited laboratory capacity. This systematic review synthesized literature on specific use cases and performance of Ag RDTs for detecting SARS-CoV-2, for the first comprehensive assessment of Ag RDT use in real-world settings. Methods: We searched three databases (PubMed, EMBASE and medRxiv) up to 12 April 2021 for publications on Ag-RDT use for large-scale screening, irrespective of symptoms, and surveillance of COVID-19, excluding studies of only presumptive COVID-19 patients. We tabulated data on the study setting, populations, type of test, diagnostic performance and operational findings. We assessed risk of bias using QUADAS-2 and an adapted tool for prevalence studies. Results: From 4313 citations, 39 studies conducted in asymptomatic and symptomatic adults were included. Study sample sizes varied from 40 to >5 million. Of 39 studies, 37 (94.9%) investigated lateral flow Ag-RDTs and two (5.1%) investigated multiplex sandwich chemiluminescent enzyme immunoassay Ag-RDTs. Six categories of testing (screening/surveillance) initiatives were identified: mass screening (n=13), targeted screening (n=11), healthcare entry testing (n=6), at-home testing (n=4), surveillance (n=4) and prevalence survey (n=1). Across studies, Ag-RDT sensitivity varied from 40% to 100%. Ag-RDTs were noted as convenient, easy-to-use and low cost, with a rapid turnaround time and high user acceptability. Risk of bias was generally low or unclear across the studies. Conclusion: This systematic review demonstrates the use of Ag-RDTs across a wide range of real-world settings for screening and surveillance of COVID-19 in both symptomatic and asymptomatic individuals. Ag-RDTs were overall found to be easy-to-use, low cost and rapid tools, when consideration is given to their implementation and interpretation. The review was funded by FIND, the global alliance for diagnostics.

Teaching application of watercolor light color technique

2020 ◽  
pp. 002072092093683
Author(s):  
Yin Shi
Keyword(s):  
Art Education ◽  
Large Scale ◽  
Low Cost ◽  
Art Curriculum ◽  
Repeated Practice ◽  
Wide Range ◽  
Light Color ◽  
Teaching Application ◽  
Design Drawing

As a branch of watercolor painting, watercolor light color has been widely used in different fields. In the field of design, designers use the convenience, quickness, transparency and brilliance of watercolor to draw a design drawing. In the field of art creation, watercolor is usually the best choice for painters to go out to sketch and create large-scale drawings. In the field of art education, watercolor tools are easy to carry, low-cost and easy to operate, which can facilitate students’ repeated practice and outside Sketching is helpful to cultivate students’ sense of color and observation ability. Therefore, as a branch of art curriculum, watercolor light color has a wide range of uses and great practicability, which is worth exploring and studying.

scholarly journals An information theoretic approach to link prediction in multiplex networks

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Seyed Hossein Jafari ◽  
Amir Mahdi Abdolhosseini-Qomi ◽  
Masoud Asadpour ◽  
Maseud Rahgozar ◽  
Naser Yazdani
Keyword(s):  
Real World ◽  
Link Prediction ◽  
Large Scale ◽  
Similarity Measures ◽  
Prediction Method ◽  
General Purpose ◽  
Fast Method ◽  
Theoretic Approach ◽  
Multiplex Networks ◽  
Wide Range

AbstractThe entities of real-world networks are connected via different types of connections (i.e., layers). The task of link prediction in multiplex networks is about finding missing connections based on both intra-layer and inter-layer correlations. Our observations confirm that in a wide range of real-world multiplex networks, from social to biological and technological, a positive correlation exists between connection probability in one layer and similarity in other layers. Accordingly, a similarity-based automatic general-purpose multiplex link prediction method—SimBins—is devised that quantifies the amount of connection uncertainty based on observed inter-layer correlations in a multiplex network. Moreover, SimBins enhances the prediction quality in the target layer by incorporating the effect of link overlap across layers. Applying SimBins to various datasets from diverse domains, our findings indicate that SimBins outperforms the compared methods (both baseline and state-of-the-art methods) in most instances when predicting links. Furthermore, it is discussed that SimBins imposes minor computational overhead to the base similarity measures making it a potentially fast method, suitable for large-scale multiplex networks.

scholarly journals Can we rely on non-randomised studies? Findings from a meta-epidemiological review

2019 ◽  
Vol 29 (Supplement_4) ◽  
Author(s):  
J C Rejon-Parrilla ◽  
M Salcher-Konrad ◽  
M Nguyen ◽  
K Davis ◽  
P Jonsson ◽  
...  
Keyword(s):  
Health Economic ◽  
Analytical Methods ◽  
Large Scale ◽  
Treatment Effects ◽  
Controlled Trial ◽  
Health Economic Evaluation ◽  
Risk Of Bias ◽  
Economic Decision Making ◽  
Wide Range ◽  
Randomised Controlled

Abstract Background Increasingly, health technology assessment (HTA) agencies must decide whether new medicines should be used routinely in the absence of randomised controlled trial (RCT) data, relying solely on non-randomised studies (NRS), which are at high risk of bias due to confounding. Against the background of increased availability and improved methods to analyse non-randomised data (e.g., propensity score methods and instrumental variables), it is important for decision-makers to have guidance on the analysis and interpretation of NRS to inform health economic evaluation. We therefore aimed to systematically and empirically assess the performance of NRS using different analytical methods as compared to RCTs and develop recommendations on the basis of our findings. Methods We conducted a large-scale meta-epidemiological review to obtain estimates of the discrepancy in treatment effects in matched RCTs and NRS of pharmacologic interventions from published meta-analyses indexed in MEDLINE and the Cochrane Database of Systematic Reviews. We also consulted with HTA bodies, regulators and academics from five European countries to learn from their experience with using non-randomised evidence. Results We compiled the largest dataset of clinical topics with matching RCTs and NRS using various analytical methods to date, covering >100 unique clinical questions. Incorporating information on direction of effect and effect size from >700 unique studies, the dataset can be used to evaluate discrepancies in treatment effects between study designs across a wide range of therapeutic areas. Conclusions An empirically based understanding of the risk of bias in NRS is required in order to promote the adequate use of non-randomised evidence as input for health economic decision-making.

scholarly journals Process Design Kit and Design Automation for Flexible Hybrid Electronics

2019 ◽  
Vol 16 (3) ◽  
pp. 117-123
Author(s):  
Tsung-Ching Huang ◽  
Ting Lei ◽  
Leilai Shao ◽  
Sridhar Sivapurapu ◽  
Madhavan Swaminathan ◽  
...  
Keyword(s):  
Process Design ◽  
Design Automation ◽  
High Performance ◽  
Large Scale ◽  
Low Cost ◽  
Thin Film Transistor ◽  
Solution Process ◽  
Oxide Semiconductor ◽  
Wearable Electronics ◽  
Wide Range

Abstract High-performance low-cost flexible hybrid electronics (FHE) are desirable for applications such as internet of things and wearable electronics. Carbon nanotube (CNT) thin-film transistor (TFT) is a promising candidate for high-performance FHE because of its high carrier mobility, superior mechanical flexibility, and material compatibility with low-cost printing and solution processes. Flexible sensors and peripheral CNT-TFT circuits, such as decoders, drivers, and sense amplifiers, can be printed and hybrid-integrated with thinned (<50 μm) silicon chips on soft, thin, and flexible substrates for a wide range of applications, from flexible displays to wearable medical devices. Here, we report (1) a process design kit (PDK) to enable FHE design automation for large-scale FHE circuits and (2) solution process-proven intellectual property blocks for TFT circuits design, including Pseudo-Complementary Metal-Oxide-Semiconductor (Pseudo-CMOS) flexible digital logic and analog amplifiers. The FHE-PDK is fully compatible with popular silicon design tools for design and simulation of hybrid-integrated flexible circuits.

scholarly journals A Systematic Review on 3D-Printed Imaging and Dosimetry Phantoms in Radiation Therapy

2019 ◽  
Vol 18 ◽  
pp. 153303381987020 ◽  
Author(s):  
Rance Tino ◽  
Adam Yeo ◽  
Martin Leary ◽  
Milan Brandt ◽  
Tomas Kron
Keyword(s):  
Systematic Review ◽  
Quality Assurance ◽  
Additive Manufacturing ◽  
Image Quality Assessment ◽  
Low Cost ◽  
Acrylonitrile Butadiene Styrene ◽  
Limiting Factors ◽  
Patient Specific ◽  
Wide Range ◽  
Assurance Process

Introduction: Additive manufacturing or 3-dimensional printing has become a widespread technology with many applications in medicine. We have conducted a systematic review of its application in radiation oncology with a particular emphasis on the creation of phantoms for image quality assessment and radiation dosimetry. Traditionally used phantoms for quality assurance in radiotherapy are often constraint by simplified geometry and homogenous nature to perform imaging analysis or pretreatment dosimetric verification. Such phantoms are limited due to their ability in only representing the average human body, not only in proportion and radiation properties but also do not accommodate pathological features. These limiting factors restrict the patient-specific quality assurance process to verify image-guided positioning accuracy and/or dose accuracy in “water-like” condition. Methods and Results: English speaking manuscripts published since 2008 were searched in 5 databases (Google Scholar, Scopus, PubMed, IEEE Xplore, and Web of Science). A significant increase in publications over the 10 years was observed with imaging and dosimetry phantoms about the same total number (52 vs 50). Key features of additive manufacturing are the customization with creation of realistic pathology as well as the ability to vary density and as such contrast. Commonly used printing materials, such as polylactic acid, acrylonitrile butadiene styrene, high-impact polystyrene and many more, are utilized to achieve a wide range of achievable X-ray attenuation values from −1000 HU to 500 HU and higher. Not surprisingly, multimaterial printing using the polymer jetting technology is emerging as an important printing process with its ability to create heterogeneous phantoms for dosimetry in radiotherapy. Conclusion: Given the flexibility and increasing availability and low cost of additive manufacturing, it can be expected that its applications for radiation medicine will continue to increase.

scholarly journals Green Preparation of Fluorescent Carbon Quantum Dots from Cyanobacteria for Biological Imaging

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 616 ◽  
Author(s):  
Xi Wang ◽  
Pei Yang ◽  
Qian Feng ◽  
Taotao Meng ◽  
Jing Wei ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Carbon Source ◽  
Large Scale ◽  
Low Cost ◽  
Average Diameter ◽  
Carbon Quantum Dots ◽  
Water Soluble ◽  
High Concentration ◽  
Wide Range ◽  
Low Cytotoxicity

Biomass-based carbon quantum dots (CQDs) have become a significant carbon materials by their virtues of being cost-effective, easy to fabricate and low in environmental impact. However, there are few reports regarding using cyanobacteria as a carbon source for the synthesis of fluorescent CQDs. In this study, the low-cost biomass of cyanobacteria was used as the sole carbon source to synthesize water-soluble CQDs by a simple hydrothermal method. The synthesized CQDs were mono-dispersed with an average diameter of 2.48 nm and exhibited excitation-dependent emission performance with a quantum yield of 9.24%. Furthermore, the cyanobacteria-derived CQDs had almost no photobleaching under long-time UV irradiation, and exhibited high photostability in the solutions with a wide range of pH and salinity. Since no chemical reagent was involved in the synthesis of CQDs, the as-prepared CQDs were confirmed to have low cytotoxicity for PC12 cells even at a high concentration. Additionally, the CQDs could be efficiently taken up by cells to illuminate the whole cell and create a clear distinction between cytoplasm and nucleus. The combined advantages of green synthesis, cost-effectiveness and low cytotoxicity make synthesized CQDs a significant carbon source and broaden the application of cyanobacteria and provide an economical route to fabricate CQDs on a large scale.

scholarly journals A Low-Cost Electromagnetic Docking Guidance System for Micro Autonomous Underwater Vehicles

Sensors ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 682 ◽  
Author(s):  
Shilin Peng ◽  
Jingbiao Liu ◽  
Junhao Wu ◽  
Chong Li ◽  
Benkun Liu ◽  
...  
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Autonomous Underwater Vehicles ◽  
Underwater Vehicles ◽  
Guidance System ◽  
Electromagnetic Signal ◽  
Spatiotemporal Resolution ◽  
Search Coil ◽  
Wide Range ◽  
Processing Subsystem

As important observational platforms for the Smart Ocean concept, autonomous underwater vehicles (AUVs) that perform long-term observation in fleets are beneficial because they provide large-scale sampling data with a sufficient spatiotemporal resolution. Therefore, a large number of low-cost micro AUVs with docking capability for power recharge and data transmission are essential. This study designed a low-cost electromagnetic docking guidance (EMDG) system for micro AUVs. The EMDG system is composed of a transmitter coil located on the dock and a three-axial search coil magnetometer acting as a receiver. The search coil magnetometer was optimized for small sizes while maintaining sufficient sensitivity. The signal conditioning and processing subsystem was designed to calculate the deflection angle (β) for docking guidance. Underwater docking tests showed that the system can detect the electromagnetic signal and successfully guide AUV docking. The AUV can still perform docking in extreme positions, which cannot be realized through normal optical or acoustic guidance. This study is the first to focus on the EM guidance system for low-cost micro AUVs. The search coil sensor in the AUV is inexpensive and compact so that the system can be equipped on a wide range of AUVs.

scholarly journals Towards the best kidney failure prediction tool: a systematic review and selection aid

2019 ◽  
Vol 35 (9) ◽  
pp. 1527-1538 ◽  
Author(s):  
Chava L Ramspek ◽  
Ype de Jong ◽  
Friedo W Dekker ◽  
Merel van Diepen
Keyword(s):  
Systematic Review ◽  
Kidney Failure ◽  
External Validation ◽  
Model Development ◽  
Risk Of Bias ◽  
Future Research ◽  
Prediction Tool ◽  
Clinical Value ◽  
Wide Range ◽  
And Performance

Abstract Background Prediction tools that identify chronic kidney disease (CKD) patients at a high risk of developing kidney failure have the potential for great clinical value, but limited uptake. The aim of the current study is to systematically review all available models predicting kidney failure in CKD patients, organize empirical evidence on their validity and ultimately provide guidance in the interpretation and uptake of these tools. Methods PubMed and EMBASE were searched for relevant articles. Titles, abstracts and full-text articles were sequentially screened for inclusion by two independent researchers. Data on study design, model development and performance were extracted. The risk of bias and clinical usefulness were assessed and combined in order to provide recommendations on which models to use. Results Of 2183 screened studies, a total of 42 studies were included in the current review. Most studies showed high discriminatory capacity and the included predictors had large overlap. Overall, the risk of bias was high. Slightly less than half the studies (48%) presented enough detail for the use of their prediction tool in practice and few models were externally validated. Conclusions The current systematic review may be used as a tool to select the most appropriate and robust prognostic model for various settings. Although some models showed great potential, many lacked clinical relevance due to being developed in a prevalent patient population with a wide range of disease severity. Future research efforts should focus on external validation and impact assessment in clinically relevant patient populations.

scholarly journals High-Sensitivity Flexible Pressure Sensor-Based 3D CNTs Sponge for Human–Computer Interaction

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3465
Author(s):  
Jianli Cui ◽  
Xueli Nan ◽  
Guirong Shao ◽  
Huixia Sun
Keyword(s):  
Pressure Sensor ◽  
High Performance ◽  
Large Scale ◽  
Low Cost ◽  
Pressure Sensors ◽  
Chemical Vapor ◽  
High Sensitivity ◽  
Wearable Electronics ◽  
Wide Range ◽  
Flexible Pressure Sensors

Researchers are showing an increasing interest in high-performance flexible pressure sensors owing to their potential uses in wearable electronics, bionic skin, and human–machine interactions, etc. However, the vast majority of these flexible pressure sensors require extensive nano-architectural design, which both complicates their manufacturing and is time-consuming. Thus, a low-cost technology which can be applied on a large scale is highly desirable for the manufacture of flexible pressure-sensitive materials that have a high sensitivity over a wide range of pressures. This work is based on the use of a three-dimensional elastic porous carbon nanotubes (CNTs) sponge as the conductive layer to fabricate a novel flexible piezoresistive sensor. The synthesis of a CNTs sponge was achieved by chemical vapor deposition, the basic underlying principle governing the sensing behavior of the CNTs sponge-based pressure sensor and was illustrated by employing in situ scanning electron microscopy. The CNTs sponge-based sensor has a quick response time of ~105 ms, a high sensitivity extending across a broad pressure range (less than 10 kPa for 809 kPa−1) and possesses an outstanding permanence over 4,000 cycles. Furthermore, a 16-pixel wireless sensor system was designed and a series of applications have been demonstrated. Its potential applications in the visualizing pressure distribution and an example of human–machine communication were also demonstrated.

scholarly journals Fabrication of Functional Materials for Dye-sensitized Solar Cells

2021 ◽  
Vol 9 ◽  
Author(s):  
Sarawut Tontapha ◽  
Pikaned Uppachai ◽  
Vittaya Amornkitbamrung
Keyword(s):  
Solar Cells ◽  
Large Scale ◽  
Low Cost ◽  
Dye Sensitized Solar Cells ◽  
Light Condition ◽  
Functional Materials ◽  
Scale Production ◽  
Dye Sensitized ◽  
Wide Range ◽  
Sensitized Solar Cells

Dye-sensitized solar cells (DSSCs) have been developed as a promising photovoltaic cell type in recent decades because of their low cost, environmental friendliness, ease of fabrication, and suitability for a wide range of indoor and outdoor applications, especially under diverse shaded and low-light condition. They are typically composed of three main components: a transparent conducting oxide (TCO) substrate-based working electrode with wide-bandgap semiconductors and dye sensitizer molecules, an electrolytic mediator based on redox couple species, and a TCO-based counter electrode consisting of catalyst materials. The development of intrinsic and functional organic, inorganic, metal oxide, composite, and carbon-based materials has been intensively studied to enhance the efficiency of DSSCs. A simple and low-cost fabrication process that uses natural products is also considered essential for further large-scale production. In this article, we review the fabrication of various functional materials and their effects on DSSC performance.

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