Ball pen writing-without-ink: a truly simple and accessible method for sensitivity enhancement in lateral flow assays

A ball pen writing-without-ink method was developed to amplify the detection signal of LFAs through controlling fluid flow rate.

Feasibility of Producing Core-Shell Filaments through Fused Filament Fabrication

Fused filament fabrication is a technology of additive manufacturing that uses molten thermoplastics for building parts. Due to the convenient shape of the raw material, a simple filament, the market offers a great variety of materials from simple to blends of compatible materials. However, finding a material with the desired properties can be difficult. Making it in-house or using a material manufacturer can be costly and time-consuming, especially when the optimum blend ratios are unknown or new design perspectives are tested. This paper presents an accessible method of producing core-shell filaments using material extrusion 3D printing. The printed filaments are characterised by a polycarbonate (PC) core and acryl butadiene styrene (ABS) shell with three material ratios. Their performance was investigated through printed samples. Additionally, the material mixing degree was studied by varying the extrusion temperature, nozzle feeding geometry, and layer thickness. The influence of all four factors was evaluated using a graphical representation of the main effects. The results showed that a core-shell filament can be processed using a 3D printer with a dual extrusion configuration and that the mechanical properties of the samples can be improved by varying the PC–ABS ratio. This research provides an accessible method for developing new hybrid filaments with a predesigned structure using a 3D printer.

COVID-19 PREVENTIVE BEHAVIOURS

COVID-19 is an infectious disease attributable to SARS-CoV-2, which is transmitted by direct and indirect transmission. There are some measures that have been introduced to society in order to prevent the spread of COVID-19 including face masks, hand hygiene, face shields, and social distancing. Face masks have become one of the most common preventive instruments against viral spreading. The primary use of face masks is to protect or contain the viral mode of transmission such as droplets. Face masks have different types that demonstrate specific uses. Hand hygiene is an accessible method that people can follow. The benefit of hand hygiene appears to be the ability to trap germs and remove them away. In a more sophisticated use, face shields are used together with face masks in order to better the performance of protecting the virus from different directions. Social distancing is known as one of the popular measures among many countries. To decrease the rate of COVID-19 infection, standing 1-2 metres is recommended. We hope that our review paper would provide useful information for the readers, which could be applied in real life. Also, we fully appreciate being a reliable supplement for the following research.

Method for Fabricating Transparent Patient-Specific Vocal Tract Replicas

Introduction Transparent, patient-specific vocal tract replicas are helpful in research and educational endeavors but challenging to procure. An accessible method for fabricating these models, improving on previously suggested processes, would make them more widely available. Method Detailed instructions for fabricating a transparent, patient-specific vocal tract model were addressed. The broad steps were (1) digitally reconstructing (patient-specific) vocal tract geometry, (2) producing a vocal tract mold (using methods such as three-dimensional [3D] printing), and (3) casting transparent material (such as silicone) around the vocal tract mold and removing the mold. The cavities remaining within the cast represented the exact geometry of the vocal tract. Discussion A combination of 3D printing and silicone casting can produce useful vocal tract replicas. Several simple changes to previous methods can improve consistency and reduce the labor and cost of production. Limitations and potential modifications to expand the applications of this method are discussed.

Irradiance footprint of phototherapy devices: a comparative study

Background Phototherapy (PT) is the standard treatment of neonatal unconjugated hyperbilirubinemia. The irradiance footprint, i.e., the illuminated area by the PT device with sufficient spectral irradiance, is essential for PT to be effective. Irradiance footprint measurements are not performed in current clinical practice. We describe a user-friendly method to systematically evaluate the high spectral irradiance (HSI) footprint (illuminated area with spectral irradiance of ≥30 μW cm−2 nm−1) of PT devices in clinical practice. Materials and methods Six commercially available LED-based overhead PT devices were evaluated in overhead configuration with an incubator. Spectral irradiance (µW cm−2 nm−1) and HSI footprint were measured with a radiospectrometer (BiliBlanket Meter II). Results The average measured spectral irradiance ranged between 27 and 52 μW cm−2 nm−1 and HSI footprint ranged between 67 and 1465 cm2, respectively. Three, two, and one PT devices out of six covered the average BSA of an infant born at 22, 26–32, and 40 weeks of gestation, respectively. Conclusion Spectral irradiance of LED-based overhead PT devices is often lower than manufacturer’s specifications, and HSI footprints not always cover the average BSA of a newborn infant. The proposed measurement method will contribute to awareness of the importance of irradiance level as well as footprint measurements in the management of neonatal jaundice. Impact While a sufficient spectral irradiance footprint is essential for PT to be effective, some PT devices have spectral irradiance footprints that are too small to cover the entire body surface area (BSA) of a newborn infant. This study introduces a user-friendly, accessible method to systematically evaluate the spectral irradiance level and footprint of PT devices. This study supports awareness on the role of the spectral irradiance footprint in the efficacy of PT devices. Irradiance footprint can be easily measured during phototherapy with the proposed method.

Development and Clinical Validation of CT-Based Regional Centiloid Method for Amyloid PET

Background: We developed and validated CT-based regional Centiloid. A CT-based regional Centiloid was developed and validated in the present study. Methods: For development ofMRI-based or CT-based regional CLs,the cohort consist of 63 subjects (20 young controls (YC) and18 old controls (OC), and 25 Alzheimer’s disease dementia (ADD)).We used direct comparison of FMM-FBB CL (dcCL) method using MRI and CT images to define a common target region and six regional VOIs including the frontal, temporal, parietal, posterior cingulate, occipital and striatal regions. Global and regional dcCL scales were compared between MRI-based and CT-based methods. For clinical validation, cohortconsisted of 2,245subjects (627 in CN, 933 in MCI, and 685 in ADD). Results: Both MRI-based and CT-based dcCL scales showed that FMM and FBB were highly correlated with each other, globally and regionally (R2 = 0.96~0.99). Both FMM and FBB showed that CT-based regional dcCL scales were highly correlated with MRI-based regional dcCL scales (R2 = 0.97~0.99). Absolute differences in regional CL scales between CT-based and MRI-based methods seemed to be relatively insignificant (p>0.05). In our clinical validation study, the G(-)R(+) and G(+)Str(+) groups predict worse neuropsychological performance than the G(-)R(-) and the G(+)Str(-) groups (p< 0.05) respectively.Conclusions: Our findings suggested that it is feasible to convert FMM or FBB dcSUVR values into the dcCL scales regionally without additional MRI scans, which might in turn become a more easily accessible method for researchers and be applicable to a variety of different conditions.

Biomarkers Utility: At the Borderline between Cardiology and Neurology

Biomarkers are important diagnostic and prognostic tools as they provide results in a short time while still being an inexpensive, reproducible and accessible method. Their well-known benefits have placed them at the forefront of research in recent years, with new and innovative discoveries being implemented. Cardiovascular and neurological diseases often share common risk factors and pathological pathways which may play an important role in the use and interpretation of biomarkers’ values. Among the biomarkers used extensively in clinical practice in cardiology, hs-TroponinT, CK-MB and NTproBNP have been shown to be strongly influenced by multiple neurological conditions. Newer ones such as galectin-3, lysophosphatidylcholine, copeptin, sST2, S100B, myeloperoxidase and GDF-15 have been extensively studied in recent years as alternatives with an increased sensitivity for cardiovascular diseases, but also with significant results in the field of neurology. Thus, given their low specificity, the values interpretation must be correlated with the clinical judgment and other available investigations.

Clinical Validation of Rapid Gout Detection Method and Kit

Gout is an inflammatory arthritis, which causes intense, acute pain due to the buildup of uric acid crystals in synovial fluid. The gold standard for gout diagnosis consists of synovial fluid analysis by polarized light microscopy, which is costly, time-intensive, and technique-dependent, therefore meriting a more efficient, inexpensive, and accessible method for diagnosis. We previously developed and validated a novel colorimetric gout detection method and device based on the reduction of silver nitrate by uric acid; here, we clinically validated our method and device using arthroscopically obtained synovial fluid samples from gout patients. We successfully identified uric acid crystals in clinical samples via our colorimetric method, visualized uric acid crystals in synovial fluid via handheld microscopy, and determined that silver nitrate stain did not interfere with the microscopic visualization of uric acid crystals necessary for diagnosis. We also developed and validated a method of processing turbid clinical samples for use in our device to prevent the obscuration of uric acid crystals by suspended material. Our method and device will clinically facilitate the immediate colorimetric diagnosis of gout and the subsequent bedside visualization of uric acid crystals in both ideal and turbid synovial fluid samples, allowing for a point-of-care diagnosis of gout.

Fast Fabrication of Solid-State Nanopores for DNA Molecule Analysis

Solid-state nanopores have been developed as a prominent tool for single molecule analysis in versatile applications. Although controlled dielectric breakdown (CDB) is the most accessible method for a single nanopore fabrication, it is still necessary to improve the fabrication efficiency and avoid the generation of multiple nanopores. In this work, we treated the SiNx membranes in the air–plasma before the CDB process, which shortened the time-to-pore-formation by orders of magnitude. λ-DNA translocation experiments validated the functionality of the pore and substantiated the presence of only a single pore on the membrane. Our fabricated pore could also be successfully used to detect short single-stranded DNA (ssDNA) fragments. Using to ionic current signals, ssDNA fragments with different lengths could be clearly distinguished. These results will provide a valuable reference for the nanopore fabrication and DNA analysis.

Submersed micropatterned structures control active nematic flow, topology, and concentration

Coupling between flows and material properties imbues rheological matter with its wide-ranging applicability, hence the excitement for harnessing the rheology of active fluids for which internal structure and continuous energy injection lead to spontaneous flows and complex, out-of-equilibrium dynamics. We propose and demonstrate a convenient, highly tunable method for controlling flow, topology, and composition within active films. Our approach establishes rheological coupling via the indirect presence of fully submersed micropatterned structures within a thin, underlying oil layer. Simulations reveal that micropatterned structures produce effective virtual boundaries within the superjacent active nematic film due to differences in viscous dissipation as a function of depth. This accessible method of applying position-dependent, effective dissipation to the active films presents a nonintrusive pathway for engineering active microfluidic systems.