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AbstractObjectiveMethodsResultsConclusionDuring the COVID-19 pandemic, information sources such as public officials, national/international media, social media, public health agencies, college/university officials, etc., played a vital role in adherence to safety measures, including hygiene practices, social distancing, and mask-wearing. We analyze the role of trusted sources of information in adherence to safety measures and explore potential disparities among US college students during the pandemic.We analyze Healthy Minds Study (HMS) 2020–2021 COVID Module data and utilize multivariable logistic regressions controlling for sociodemographic and COVID-19-related factors. Subgroup analyses were conducted by gender, citizenship status, race, and educational level.Significant differences were found in adherence to safety measures when information was received from different sources. Demographic subgroups within the college student population depended on different sources of COVID-19-related information. Adherence to COVID-19-related safety measures also differed by demographic characteristics.This analysis supports the necessity for targeted health-related messaging among US college students. [ABSTRACT FROM AUTHOR]

This paper presents an intelligent design method for a corner-truncated microstrip patch antenna (CTMPA) operating at 32 GHz using various well-known machine learning (ML) techniques. Our objectives are to obtain a gain of >5 dBic across a 10% bandwidth, an axial ratio (AR) of <3 dB, and a return loss of <−10 dB. First, a dataset of 715 full-wave simulated samples is analyzed with four distinct antenna characteristics (viz. features), along with the related computed | S 11 | , gain, and AR. Using mean absolute error (MAE), mean square error (MSE), root mean square error (RMSE), and R 2 score, 12 ML regression models were examined to compare the training data with the new predicted values. Next, the model that best satisfies our objectives was chosen. Results showed that the artificial neural network (ANN) followed by k-nearest neighbor (KNN) regression produced the lowest error compared to all tested ML models. The design parameters that achieved our intended objectives were computed using the predicted results. The predicted design was validated using a full-wave simulation and a prototype measurement. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method to generate Vector Vortex Modes (VVM) inside a metallic cylindrical waveguide at microwave frequencies and demonstrate the experimental validation of the concept. Vector vortex modes of EM waves can carry both spin and orbital angular momentum as they propagate within a tubular medium. The existence of such waves in tubular media can be beneficial to wireless communication in such structures. These waves can carry different orbital angular momentum and spin angular momentum, and therefore, they feature the ability to carry multiple orthogonal modes at the same frequency due to spatial structure of the phase and polarization. In essence, high data rate channels can be developed using such waves. In free space, Orbital Angular Momentum carrying vortex waves have beam divergence issues and a central field-minima, which makes these waves unfavorable for free space communication. But vector vortex mode waves in guided structures do not suffer from these drawbacks. This prospect of enhancement of communication spectrum in waveguides provides the background for the study of vortex wave in circular waveguides. In this work, new feed structures and a radial array of monopoles are designed to generate the VVM carrying waves inside the waveguide. The experimental findings on the distribution of the amplitude and phase of the electromagnetic fields inside the waveguide are presented and the relationship between the waveguide fundamental modes and VVMs are discussed for the first time. The paper also presents methods for varying the cutoff frequency of the VVMs by introducing dielectric materials in the waveguide. [ABSTRACT FROM AUTHOR]

This study examines the online niches of English-language newspapers in Bangladesh by analyzing stories and user engagement on the Facebook pages of five highest circulated newspapers. Based on the theory of the niche, this study analyzed data on 17,687 Facebook posts downloaded programmatically. Results indicate that users read these newspapers for in-depth news stories and features on diplomacy, national security, lifestyle, science, technology, and international events. The study identified a gap between what these newspapers offer and what their users want. [ABSTRACT FROM AUTHOR]