Ageism on Twitter during the COVID-19 pandemic.

The COVID-19 crisis has sparked a resurgence of scholarly interest in the issue of ageism. Whether the outbreak thwarts or facilitates efforts to combat ageism hinges upon public sentiments toward the older demographic. This study aims to explore discourse surrounding older adults by analyzing 183,179 related tweets posted during the COVID-19 pandemic from February to December 2020. Overall, sentiments toward older adults became significantly less negative over time, being the least negative in April, August, and October, though the score remained below the neutral value throughout the 11 months. Our topic modelling analysis generated four themes: "The Need to Protect Older Adults" (41%), "Vulnerability and Mortality" (36%), "Failure of Political Leadership" (12%), and "Resilience" (11%). These findings indicate nascent support for older adults, though attempts to show solidarity may well worsen benevolent ageism.

Regenerable and high-throughput surface plasmon resonance assay for rapid screening of anti-SARS-CoV-2 antibody in serum samples.

Current serological antibody tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) require enzyme or fluorescent labels, and the titer well plates cannot be reused. By immobilizing histidine (His)-tagged SARS-CoV-2 spike (S1) protein onto tris‒nitrilotriacetic acid (tris-NTA) sensor and using the early association phase for mass-transfer-controlled concentration determination, we developed a rapid and regenerable surface plasmon resonance (SPR) method for quantifying anti-SARS-CoV-2 antibody. On a five-channel SPR instrument and with optimized S1 protein immobilization density, each of the four analytical channels is sequentially used for multiple measurements, and all four channels can be simultaneously regenerated once they have reached a threshold value. Coupled with a programmable autosampler, each sensor can be regenerated at least 20 times, enabling uninterrupted assays of more than 800 serum samples. The accuracy and speed of our method compare well with those of the enzyme-linked immunosorbent assay (ELISA), and the detection limit (0.057 µg mL-1) can easily meet the requirement for screening low antibody levels such as those in convalescent patients. In addition, our method exhibits excellent channel-to-channel (RSD = 1.9%) and sensor-to-sensor (RSD = 2.1%) reproducibility. Obviation of an enzyme label drastically reduced the assay cost, rending our method (<60 cents) much more cost effective than those of commercial ELISA kits ($4.4-11.4). Therefore, our method offers a cost-effective and high-throughput alternative to the existing methods for serological measurements of anti-SARS-CoV-2 antibody levels, holding great promise for rapid screening of clinical samples without elaborate sample pretreatments and special reagents.

[Isothermal amplification technology based on microfluidic chip].

Polymerase chain reaction (PCR) is the gold standard for nucleic acid amplification in molecular diagnostics. The PCR includes multiple reaction stages (denaturation, annealing, and extension), and a complicated thermalcycler is required to repetitively provide different temperatures for different stages for 30-40 cycles within at least 1-2 hours. Due to the complicated devices and the long amplification time, it is difficult to adopt conventional PCR in point-of-care testing (POCT). Comparing to conventional PCR, isothermal amplification is able to provide a much faster and more convenient nucleic acid detection because of highly efficient amplification at a constant reaction temperature provided by a simple heating device. When isothermal amplification is combined with microfluidics, a more competent platform for POCT can be established. For example, various diagnosis devices based on isothermal amplification have been used to rapidly and conveniently detect SARS-CoV-2 viruses. This review summarized the recent development and applications of the microfluidics-based isothermal amplification. First, different typical isothermal amplification methods and related detection methods have been introduced. Subsequently, different types of microfluidic systems with isothermal amplification were discussed based on their characteristics, for example, functionality, system structure, flow control, and operation principles. Furthermore, detection of pathogens (e.g. SARS-CoV-2 viruses) based on isothermal amplification was introduced. Finally, the combination of isothermal amplification with other new technologies, e.g. CRISPR, has been introduced as well.

Pharmacy Student Challenges and Strategies towards Initial COVID-19 Curriculum Changes.

Due to COVID-19, tertiary institutions were forced to deliver knowledge virtually, which proposed challenges for both institutions and students. In this study, we aimed to characterize pharmacy students' challenges and strategies during COVID-19 curriculum changes, therefore developing a comprehensive understanding of students' learning, wellbeing, and resilience in the ever-changing situation. Data were collected from student written reflections across four year levels at one school of pharmacy from March-May 2020. In addition, data were collected from written responses of second-year pharmacy students responding to prompted questions. The data were qualitatively analyzed inductively by five coders using NVivo 12. For each piece of data, two coders independently coded the data, calculated the inter-rater agreement, and resolved discrepancies. The most coded challenges were 'negative emotional response' and 'communication barrier during virtual learning'. The most coded strategies were 'using new technology' and 'time management'. This study allows researchers and education institutions to gain an overview of pharmacy students' experiences during COVID-19, therefore helping universities to provide students with necessary support and techniques on how to self-cope with COVID-19 as well as stressful events in the future.

Rapid PCR powered by microfluidics: A quick review under the background of COVID-19 pandemic.

PCR has been widely used in different fields including molecular biology, pathogen detection, medical diagnosis, food detection and etc. However, the difficulty of promoting PCR in on-site point-of-care testing reflects on challenges relative to its speed, convenience, complexity, and even cost. With the emerging state-of-art of microfluidics, rapid PCR can be achieved with more flexible ways in micro-reactors. PCR plays a critical role in the detection of SARS-CoV-2. Under this special background of COVID-19 pandemic, this review focuses on the latest rapid microfluidic PCR. Rapid PCR is concluded in two main features, including the reactor (type, size, material) and the implementation of thermal cycling. Especially, the compromise between speed and sensitivity with microfluidic PCR is explored based on the system ratio of (thermal cycling time)/(reactor size). Representative applications about the detection of pathogens and SARS-CoV-2 viruses based on rapid PCR or other isothermal amplification are discussed as well.

Seepage Time Soft Sensor Model of Nonwoven Fabric Based on the Extreme Learning Machine Integrating Monte Carlo.

Nonwoven fiber materials are materials with multifunctional purposes, and are widely used to make masks for preventing the new Coronavirus Disease 2019. Because of the complexity and particularity of their structure, it becomes difficult to model the penetration and flow characteristics of liquid in nonwoven fiber materials. In this paper, a novel seepage time soft sensor model of nonwoven fabric, based on Monte Carlo (MC), integrating extreme learning machine (ELM) (MCELM) is proposed. The Monte Carlo method is used to expand data samples. Then, an ELM method is used to establish the prediction model of the dyeing time of the nonwoven fiber material overlaps with the porous medium, as well as the insertion degree and height of the different quantity of hides. Compared with the back propagation (BP) neural network and radial basis function (RBF) neural network, the results show that the prediction model based on the MCELM method has significant power in terms of accuracy and prediction speed, which is conducive to the precise and rapid manufacture of nonwoven fiber materials in practical applications between liquid seepage characteristics and structural characteristics of porous media. Furthermore, the relationship between the proposed models has certain value for predicting the behavior and use of nonwoven fiber materials with different structural characteristics and related research processes.