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Abstract Since 2002, three novel coronavirus outbreaks have occurred: severe acute respiratory syndrome coronavirus (SARS-CoV-1), Middle East respiratory syndrome coronavirus (MERS-CoV), and SARS-CoV-2. A better understanding of the transmission potential of coronaviruses will result in adequate infection control precautions and an early halt of transmission within the human population. Experiments on the stability of coronaviruses in the environment, as well as transmission models, are thus pertinent. Here, we show that transgenic mice expressing human DPP4 can be infected with MERS-CoV via the aerosol route. Exposure to 5 × 106 TCID50 and 5 × 104 TCID50 MERS-CoV per cage via fomites resulted in transmission in 15 out of 20 and 11 out of 18 animals, respectively. Exposure of sentinel mice to donor mice one day post inoculation with 105 TCID50 MERS-CoV resulted in transmission in 1 out of 38 mice via direct contact and 4 out of 54 mice via airborne contact. Exposure to donor mice inoculated with 104 TCID50 MERS-CoV resulted in transmission in 0 out of 20 pairs via direct contact and 0 out of 5 pairs via the airborne route. Our model shows limited transmission of MERS-CoV via the fomite, direct contact, and airborne routes. The hDPP4 mouse model will allow assessment of the ongoing evolution of MERS-CoV in the context of acquiring enhanced human-to-human transmission kinetics and will inform the development of other transmission models.

An animal model that fully recapitulates severe COVID-19 presentation in humans has been a top priority since the discovery of SARS-CoV-2 in 2019. Although multiple animal models are available for mild to moderate clinical disease, models that develop severe disease are still needed. Mink experimentally infected with SARS-CoV-2 developed severe acute respiratory disease, as evident by clinical respiratory disease, radiological, and histological changes. Virus was detected in nasal, oral, rectal, and fur swabs. Deep sequencing of SARS-CoV-2 from oral swabs and lung tissue samples showed repeated enrichment for a mutation in the gene encoding nonstructural protein 6 in open reading frame 1ab. Together, these data indicate that American mink develop clinical features characteristic of severe COVID-19 and, as such, are uniquely suited to test viral countermeasures.

Summary: Background: Crimean-Congo hemorrhagic fever virus is the cause of a severe hemorrhagic fever with cases reported throughout a wide-geographic region. Spread by the bite of infected ticks, contact with infected livestock or in the health care setting, disease begins as a non-specific febrile illness that can rapidly progress to hemorrhagic manifestations. Currently, there are no approved vaccines and antivirals such as ribavirin have unclear efficacy. Thus treatment is mostly limited to supportive care. Methods: In this report we evaluated an alphavirus-based replicon RNA vaccine expressing either the CCHFV nucleoprotein or glycoprotein precursor in a stringent, heterologous lethal challenge mouse model. Findings: Vaccination with the RNA expressing the nucleoprotein alone could confer complete protection against clinical disease, but vaccination with a combination of both the nucleoprotein and glycoprotein precursor afforded robust protection against disease and viral replication. Protection from lethal challenge required as little as a single immunization with 100ng of RNA. Unexpectedly, analysis of the immune responses elicited by the vaccine components showed that vaccination resulted in antibodies against the internal viral nucleoprotein and cellular immunity against the virion-exposed glycoproteins. Interpretation: Cumulatively this vaccine conferred robust protection against Crimean-Congo hemorrhagic fever virus and supports continued development of this vaccine candidate. Funding: This research was supported by the Intramural Research Program of the NIAID/NIH and HDT Bio.

Cellular and molecular mechanisms driving morbidity following SARS-CoV-2 infection have not been well defined. The receptor for advanced glycation end products (RAGE) is a central mediator of tissue injury and contributes to SARS-CoV-2 disease pathogenesis. In this study, we temporally delineated key cell and molecular events leading to lung injury in mice following SARS-CoV-2 infection and assessed efficacy of therapeutically targeting RAGE to improve survival. Early following infection, SARS-CoV-2 replicated to high titers within the lungs and evaded triggering inflammation and cell death. However, a significant necrotic cell death event in CD45– populations, corresponding with peak viral loads, was observed on day 2 after infection. Metabolic reprogramming and inflammation were initiated following this cell death event and corresponded with increased lung interstitial pneumonia, perivascular inflammation, and endothelial hyperplasia together with decreased oxygen saturation. Therapeutic treatment with the RAGE antagonist FPS-ZM1 improved survival in infected mice and limited inflammation and associated perivascular pathology. Together, these results provide critical characterization of disease pathogenesis in the mouse model and implicate a role for RAGE signaling as a therapeutic target to improve outcomes following SARS-CoV-2 infection.

This article presents a validation study of the popular aeroservoelastic code suite OpenFAST leveraging weeks of measurements obtained during normal operation of a 2.8 MW land-based wind turbine. Measured wind conditions were used to generate one-to-one turbulent flow fields (i.e., comparing simulation to measurement in 10 min increments, or bins) through unconstrained and constrained assimilation methods using the kinematic turbulence generators TurbSim and PyConTurb. A total of 253 bins of 10 min of normal turbine operation were selected for analysis, and a statistical comparison in terms of performance and loads is presented. We show that successful validation of the model was not strongly dependent on the type of inflow assimilation method used for mean quantities of interest, which had median modeling errors per wind-speed interval generally within 5 %–10 % of the measurement. The type of inflow assimilation method did have a larger effect on the fatigue predictions for blade-root flapwise and tower-base fore–aft quantities, which surprisingly saw larger errors from the assumed higher-fidelity assimilation methods. Avenues for further work are discussed and include possible improvements to the aerodynamic, structural, and controller modeling that may offer insight on the origin of the up to ∼ 40 % median overprediction of fatigue for these quantities. [ABSTRACT FROM AUTHOR]

This paper is a socio-linguistic report of Veun Sai, a small Cambodian village in the Northeastern province of Ratanakiri near the border of Laos and Vietnam. The village is located in a multi-lingual context where Hakka Chinese, Khmer, and Laotian are spoken side-by-side and each language has a distinct role. Hence, the Veun Sai Chinese village is in fact a multi-cultural village bound together by a Chinese thread. This paper provides background on Chinese communities Cambodia historically and considers issues of identity relevant to Sino-Cambodians generally. The report is based on short interviews with 20 residents. [ABSTRACT FROM AUTHOR]

Should the writing construct be assessed through handwriting or keyboarding? As the only major language entirely without a syllabary or alphabet, the Chinese writing system is unique among modern languages, thus the question of writing proficiency is complicated by character recall. Most of the testing research comparing text entry methods has been conducted in English and has found that keyboarding and handwriting can be used interchangeably. This paper reports the outcome of a study comparing the results of handwritten and typed versions of the Chinese ACTFL Writing Proficiency Test (WPT). L2 Chinese students (n = 25) with Intermediate to Superior speaking skills were randomly divided into two groups and took both WPT versions in a counterbalanced design. Keyboarding resulted in significantly higher test scores [repeated measures ANOVA F(1, 23) = 62.7, p <.001, effect size partial eta squared =.73]. Keyboarding was on average 1.69 ACTFL sublevels higher than handwriting. Finally, this paper will discuss the writing construct in Chinese along with pedagogical implications around curricular decisions on teaching and assessing handwriting vs. keyboarding. [ABSTRACT FROM AUTHOR]

Abstract Background Though social determinants are the primary drivers of health, few studies of people living with HIV focus on non-clinical correlates of insecure and/or fragmented connections with the care system. Our team uses linked clinical and multisector non‐clinical data to study how residential mobility and connection to social services influence the HIV care continuum. We engage a diverse group of individuals living with HIV and other invested community members to guide and inform this research. Our objective is to generate consultant-informed, research-based interventions that are relevant to the community, and to share our engagement approach and findings so that other researchers can do the same. Methods Our research team partnered with the Indiana Clinical and Translational Sciences Institute’s Research Jam to develop and implement a human-centered design research plan to engage individuals with experience relevant to our research. We recruited a panel of consultants composed of people living with HIV and/or clinicians and individuals from agencies that provide medical and non-medical services to people living with HIV in Marion County, Indiana. To date, we have used a variety of human-centered design tools and activities to engage individuals during six sessions, with results informing our future engagement and research activities. Results Since the inception of the project, 48 consultants have joined the panel. Thirty-five continue to be actively engaged and have participated in one or more of the six sessions conducted to date. Consultants have helped guide and prioritize analyses, aided in identification of data missing from our ecosystem, helped interpret results, provided feedback on future interventions, and co-presented with us at a local health equity conference. Conclusions We utilize community engagement to expand the scope of our research and find that the process provides value to both consultants and the research team. Human-centered design enhances this partnership by keeping it person-centered, developing empathy and trust between consultants and researchers, increasing consultant retention, and empowering consultants to collaborate meaningfully with the research team. The use of these methods is essential to conduct relevant, impactful, and sustainable research. We anticipate that these methods will be important for academic and public health researchers wishing to engage with and integrate the ideas of community consultants.