A5046339009- Indoor Air Quality and Microbial Exposure
- Air Quality and Health Impacts
- Atmospheric chemistry and aerosols
- Air Quality Monitoring and Forecasting
- Infection Control and Ventilation
- Atmospheric aerosols and clouds
- Particle Dynamics in Fluid Flows
- COVID-19 and healthcare impacts
- COVID-19 epidemiological studies
- Orbital Angular Momentum in Optics
- SARS-CoV-2 detection and testing
- Atmospheric Ozone and Climate
- Aeolian processes and effects
- Spectroscopy Techniques in Biomedical and Chemical Research
- Infection Control in Healthcare
- CRISPR and Genetic Engineering
- Optical Polarization and Ellipsometry
- COVID-19 impact on air quality
- Microbial Community Ecology and Physiology
- Disaster Response and Management
- Microfluidic and Bio-sensing Technologies
- COVID-19 and Mental Health
- Viral Infections and Outbreaks Research
- Viral Infections and Immunology Research
- Atmospheric and Environmental Gas Dynamics
University of Nebraska Medical Center
2019-2025
National Strategic Research Institute
2019-2025
Strategic Analysis (United States)
2019-2023
Sandia National Laboratories
2013-2022
The National Institute for Strategic Studies
2020-2021
Baylor University
2020
Rambam Health Care Campus
2020
Nebraska Medical Center
2019
Indiana University Bloomington
2019
University of Nebraska–Lincoln
2019
Abstract The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) originated in Wuhan, China late 2019, and its resulting disease, COVID-19, was declared a pandemic by the World Health Organization on March 11, 2020. rapid global spread of COVID-19 represents perhaps most significant public health emergency century. As progressed, continued paucity evidence routes SARS-CoV-2 transmission has resulted shifting infection prevention control guidelines between classically-defined...
Abstract Lack of evidence on SARS-CoV-2 transmission dynamics has led to shifting isolation guidelines between airborne and droplet precautions. During the initial 13 individuals confirmed positive with COVID-19 infection, air surface samples were collected in eleven rooms examine viral shedding from isolated individuals. While all for SARS-CoV-2, symptoms environment varied considerably. Many commonly used items, toilet facilities, had contamination, indicating that is shed as expired...
Abstract Background Aerosol transmission of COVID-19 is the subject ongoing policy debate. Characterizing aerosol produced by people with critical to understanding role aerosols in transmission. Objective We investigated presence virus size-fractioned from six patients admitted into mixed acuity wards April 2020. Methods Size-fractionated samples and size distributions were collected positive patients. analyzed for viral RNA, cultured Vero E6 cells. Serial RT-PCR cells indicated where...
Liquid metal–elastomer composite is a promising soft conductor for skin-interfaced bioelectronics, robots, and others due to its large stretchability, ultrasoftness, high electrical conductivity, mechanical-electrical decoupling. However, it often suffers from deformation-induced leakage, which can smear skin, deteriorate device performance, cause circuit shorting. Besides, antimicrobial property desirable in conductors minimize microbial infections. Here, we report phase separation–based...
Viruses and other pathogens that transmit as aerosols pose a significant risk to the public, due potential for widespread disease transmission. These viral diseases may be transmitted from person-to-person, such SARS-CoV-2, or environmentally generated aerosols, like hantaviruses. The threat pathogen an aerosol depends on several factors, including its stability aerosol. Bioaerosol is generally studied decay of properties (e.g., viability, infectivity and/or detectability) in response...
Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission causing disease 2019 (COVID-19) may occur through multiple routes. We collected aerosol samples around six patients admitted into mixed acuity wards in April of 2020 to identify the risk airborne SARS-CoV-2. Measurements were made characterize size distribution particles, and size-fractionated, assess presence infectious virus particles sizes >4.1 µm, 1-4 <1 µm patient environment. Samples analyzed by...
<h3>Importance</h3> Scalable programs for school-based SARS-CoV-2 testing and surveillance are needed to guide in-person learning practices inform risk assessments in kindergarten through 12th grade settings. <h3>Objectives</h3> To characterize infections staff students an urban public school setting evaluate test-based strategies support ongoing assessment mitigation learning. <h3>Design, Setting, Participants</h3> This pilot quality improvement program engaged 3 schools Omaha, Nebraska,...
Elastic light scattering (ELS) from single micron-sized particles has been used as a fast, non-destructive diagnostic tool in life science, physics, chemistry, climatology, and astrophysics. Due to the large cross-section, ELS can be find trace amounts of suspect such bioaerosols among complex, diverse atmospheric aerosols, based on single-particle interrogation. In this article, we briefly summarized main computational models instrumentation developed for ELS, then reviewed how properties...
Aerosols generated from the human respiratory tract containing infectious virus can be challenging to measure due a number of factors that impact infectivity they contain. These include limitations in understanding aerosol composition, chemical processes change composition and infectivity, effects collection process. The aerobiological pathway represents framework understand how influencing these particles collectively contribute overall their potential infectiousness. Here, is used...
This paper describes a mathematical model of fluorescent biological particles composed bacteria, viruses, or proteins. The and/or light absorbing molecules included in the are amino acids (tryptophan, etc.); nucleic (DNA, RNA, coenzymes (nicotinamide adenine dinucleotides, flavins, and vitamins B₆ K variants these); dipicolinates. concentrations, absorptivities, fluorescence quantum yields estimated from literature, often with large uncertainties. bioparticles spherical homogeneous....
This paper uses a mathematical model of fluorescent biological particles composed bacteria and/or proteins (mostly as in Hill et al., 2013 [23]) to investigate the size-dependence total fluorescence emitted all directions. The applies which have negligible reabsorption within particle. specific modeled here are ovalbumin and generic Bacillus. need not be spherical, some cases homogeneous. However, results calculated this for spherical homogeneous particles. Light absorbing fluorescing...
Following the COVID-19 outbreak, swabs for biological specimen collection were thrust to forefront of healthcare materials. Swab sample and recovery are vital reducing false negative diagnostic tests, early detection pathogens, harvesting DNA from limited samples. In this study, we report a new class nanofiber tipped with hierarchical 3D objects produced by expanding electrospun membranes solids-of-revolution-inspired gas foaming technique. Nanofiber significantly improve absorption release...
We describe an integrated opto-aerodynamic system and demonstrate that it enables us to trap absorbing airborne micron-size particles from air, hold them then release them, repeat this sequence many times as would be appropriate for continuous sampling of air. The key parts the are a conical photophoretic optical counter-flow coaxial-double-nozzle concentrates slows trapping. This technology should useful on-line applications require monitoring (by single particle analyses) series...
During the summer of 2002 a modified tandem differential mobility analyzer (TDMA) was used to examine size‐resolved hydration state ambient aerosol in southeast Texas. Throughout study period sampled had been exposed relative humidity (RH) greater than 80% before or soon after sunrise, while RH during sampling ranged from about 50 70%. To any possible size dependence, also maximizing time resolution, 160 and 320 nm particles were analyzed. assist interpretation these data, second,...
A system for measuring spectrally-resolved fluorescence cross sections of single bioaerosol particles has been developed and employed in a biological safety level 3 (BSL-3) facility at Edgewood Chemical Biological Center (ECBC). It is used to aerosolize the slurry or solution live agents surrogates into dried micron-size particles, measure spectra sizes one time. Spectrally-resolved were measured (1) bacterial spores: Bacillus anthracis Ames (BaA), B. atrophaeus var. globigii (BG) (formerly...
Detection and characterization of the presence chemical agent aerosols in various complex atmospheric environments is an essential defense mission. Raman spectroscopy has ability to identify molecules, but there are limited numbers photons detectable from single airborne aerosol particles as they flowing through a detection system. In this paper, we report on single-particle spectrometer system that can measure strong spontaneous, stimulated, resonance spectral peaks laser-trapped particle,...
A laboratory system for exposing aerosol particles to ozone and rapidly measuring the subsequent changes in their single-particle fluorescence is reported. The consists of a rotating drum chamber spectrometer (SPFS) utilizing excitation at 263 nm. Measurements made with this show preliminary results on ultra-violet laser-induced-fluorescence (UV-LIF) spectra single aerosolized Yersinia rohdei, MS2 (bacteriophage) exposed ozone. When bioparticles are emission peak around 330 nm: i) decreases...
The effects of ozone and relative humidity (RH) at common atmospheric levels on the properties single octapeptide bioaerosol particles were studied using an improved rotating reaction chamber, aerosol generator, ultraviolet aerodynamic particle sizer (UVAPS), fluorescence spectrometer (SPFS), equipments to generate, monitor control RH. Aerosol (mean diameter ~2 μm) generated from a slurry in phosphate buffered saline, injected into kept airborne for hours. Bioaerosols sampled chamber hourly...