Mounting reports in the media suggest that the COVID-19 pandemic has intensified prejudice and discrimination against racial/ethnic minorities, especially Asians. Existing research has focused on discrimination against Asians and is primarily based on self-reported incidents or nonrepresentative samples. We investigate the extent to which COVID-19 has fueled prejudice and discrimination against multiple racial/ethnic minority groups in the United States by examining nationally representative survey data with an embedded vignette experiment about roommate selection (collected in August 2020; n = 5,000). We find that priming COVID-19 salience has an immediate, statistically significant impact: compared to the control group, respondents in the treatment group exhibited increased prejudice and discriminatory intent against East Asian, South Asian, and Hispanic hypothetical room-seekers. The treatment effect is more pronounced in increasing extreme negative attitudes toward the three minority groups than decreasing extreme positive attitudes toward them. This is partly due to the treatment increasing the proportion of respondents who perceive these minority groups as extremely culturally incompatible (Asians and Hispanics) and extremely irresponsible (Asians). Sociopolitical factors did not moderate the treatment effects on attitudes toward Asians, but prior social contact with Hispanics mitigated prejudices against them. These findings suggest that COVID-19–fueled prejudice and discrimination have not been limited to East Asians but are part of a broader phenomenon that has affected Asians generally and Hispanics as well.

ImportanceBirth in the periviable period between 22 weeks 0 days and 25 weeks 6 days’ gestation is a major source of neonatal morbidity and mortality, and the decision to initiate active life-saving treatment is challenging.ObjectiveTo assess whether the frequency of active treatment among live-born neonates in the periviable period has changed over time and whether active treatment differed by gestational age at birth and race and ethnicity.Design, Setting, and ParticipantsSerial cross-sectional descriptive study using National Center for Health Statistics natality data from 2014 to 2020 for 61 908 singleton live births without clinical anomalies between 22 weeks 0 days and 25 weeks 6 days in the US.ExposuresYear of delivery, gestational age at birth, and race and ethnicity of the pregnant individual, stratified as non-Hispanic Asian/Pacific Islander, non-Hispanic Black, Hispanic/Latina, and non-Hispanic White.Main Outcomes and MeasuresActive treatment, determined by whether there was an attempt to treat the neonate and defined as a composite of surfactant therapy, immediate assisted ventilation at birth, assisted ventilation more than 6 hours in duration, and/or antibiotic therapy. Frequencies, mean annual percent change (APC), and adjusted risk ratios (aRRs) were estimated.ResultsOf 26 986 716 live births, 61 908 (0.2%) were periviable live births included in this study: 5% were Asian/Pacific Islander, 37% Black, 24% Hispanic, and 34% White; and 14% were born at 22 weeks, 21% at 23 weeks, 30% at 24 weeks, and 34% at 25 weeks. Fifty-two percent of neonates received active treatment. From 2014 to 2020, the overall frequency (mean APC per year) of active treatment increased significantly (3.9% [95% CI, 3.0% to 4.9%]), as well as among all racial and ethnic subgroups (Asian/Pacific Islander: 3.4% [95% CI, 0.8% to 6.0%]); Black: 4.7% [95% CI, 3.4% to 5.9%]; Hispanic: 4.7% [95% CI, 3.4% to 5.9%]; and White: 3.1% [95% CI, 1.1% to 4.4%]) and among each gestational age range (22 weeks: 14.4% [95% CI, 11.1% to 17.7%] and 25 weeks: 2.9% [95% CI, 1.5% to 4.2%]). Compared with neonates born to White individuals (57.0%), neonates born to Asian/Pacific Islander (46.2%; risk difference [RD], −10.81 [95% CI, −12.75 to −8.88]; aRR, 0.82 [95% CI, [0.79-0.86]), Black (51.6%; RD, −5.42 [95% CI, −6.36 to −4.50]; aRR, 0.90 [95% CI, 0.89 to 0.92]), and Hispanic (48.0%; RD, −9.03 [95% CI, −10.07 to −7.99]; aRR, 0.83 [95% CI, 0.81 to 0.85]) individuals were significantly less likely to receive active treatment.Conclusions and RelevanceFrom 2014 to 2020 in the US, the frequency of active treatment among neonates born alive between 22 weeks 0 days and 25 weeks 6 days significantly increased, and there were differences in rates of active treatment by race and ethnicity.

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Modeling and trajectory tracking control of a novel six-rotor unmanned aerial vehicle (UAV) is concerned to solve problems such as smaller payload capacity and lack of both hardware redundancy and anticrosswind capability for quad-rotor. The mathematical modeling for the six-rotor UAV is developed on the basis of the Newton-Euler formalism, and a second-order sliding-mode disturbance observer (SOSMDO) is proposed to reconstruct the disturbances of the rotational dynamics. In consideration of the under-actuated and strong coupling properties of the six-rotor UAV, a nested double loops trajectory tracking control strategy is adopted. In the outer loop, a position error PID controller is designed, of which the task is to compare the desired trajectory with real position of the six-rotor UAV and export the desired attitude angles to the inner loop. In the inner loop, a rapid-convergent nonlinear differentiator (RCND) is proposed to calculate the derivatives of the virtual control signal, instead of using the analytical differentiation, to avoid “differential expansion” in the procedure of the attitude controller design. Finally, the validity and effectiveness of the proposed technique are demonstrated by the simulation results.

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