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Health care facility ventilation design greatly affects disease transmission by aerosols. The desire to control infection in hospitals and at the same time to reduce their carbon footprint motivates the use of unconventional solutions for building design and associated control measures. This paper considers indoor sources and types of infectious aerosols, and pathogen viability and infectivity behaviors in response to environmental conditions. Aerosol dispersion, heat and mass transfer, deposition in the respiratory tract, and infection mechanisms are discussed, with an emphasis on experimental and modeling approaches. Key building design parameters are described that include types of ventilation systems (mixing, displacement, natural and hybrid), air exchange rate, temperature and relative humidity, air flow distribution structure, occupancy, engineered disinfection of air (filtration and UV radiation), and architectural programming (source and activity management) for health care facilities. The paper describes major findings and suggests future research needs in methods for ventilation design of health care facilities to prevent airborne infection risk

Cognitive interviewing of the US National Cancer Institute’s Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE)

The National Cancer Institute’s Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) is a library of question items that enables patient reporting of adverse events (AEs) in clinical trials. This study contributes content validity evidence of the PRO-CTCAE by incorporating cancer patient input of the relevance and comprehensiveness of the item library

Validity and Reliability of the US National Cancer Institute’s Patient-Reported Outcomes Version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE)

Symptomatic adverse events (AEs) in cancer trials are currently reported by clinicians using the National Cancer Institute's (NCI) Common Terminology Criteria for Adverse Events (CTCAE). To integrate the patient perspective, the NCI developed a patient-reported outcomes version of the CTCAE (PRO-CTCAE) to capture symptomatic AEs directly from patients

Aerosol dynamics of agglomerates

The mobility, charging, coagulation and mass-transfer properties of aerosol agglomerates were related to the particle and the background gas mean free path λ. The mobility-equivalent diameter dm of a self-similar cluster of spheres in the continuum regime λ&#60;&#60;dm was calculated to be proportional to the radius of gyration Rg of the cluster for fractal dimension Df&#62;1.3. Slender-body behavior is approached for Df&#60;1.3. In the free-molecule regime dm&#60;&#60;λ, dm is nearly equal to the projected-area diameter dA. In the transition regime dm~λ, dm depends on both dA and Rg. In general, there is a divergence of dA and Rg as the agglomerate size increases, but it is very gradual for typical aerosol agglomerates, for which dm~dA in the transition regime. The mass transfer of nanometer-sized 211Pb clusters to TiO2 agglomerates was investigated with an Epiphaniometer. The measured mass-transfer-equivalent diameters of the agglomerates were within 10% of dm. The lead cluster mean free path was nearly the same as λ. For an analogous phenomenon, the bipolar diffusion charging of agglomerates, it was found that the charging-equivalent diameter of the agglomerates was ~10% larger than dm. These measurements were incorporated into a model describing the coagulation of agglomerates in the transition regime. Particles smaller than the primary particle diameter d1 were assumed to coalesce rapidly, while large particles were assumed to be solid with a fractal structure. In the transition regime, the agglomerate mean free paths are much smaller than dm even when dm&#60; λ. This leads to distinctly different dynamic behavior than predicted by previous models developed for the continuum or free-molecule regimes. The enhancement of coagulation over that of dense spheres is large for aerosols with median diameters slightly greater than d1 but smaller for aerosols consisting of much larger particles.</p

The Effect of Primary Particle Polydispersity on the Morphology and Mobility Diameter of the Fractal Agglomerates in Different Flow Regimes

Properties of colloidal and aerosol agglomerates depend on their morphology. Accurate estimation of the mobility-equivalent diameter m in different flow regimes is essential in many industrial processes and measurements. Previous work on the hydrodynamic properties of clusters focussed on agglomerates composed of monodisperse primary particles. However aggregates formed in real processes, e.g. soot particles, are usually formed from polydisperse monomers. Using numericallygenerated agglomerates it is shown here that the radius of gyration, surface area, and mass of the agglomerates increase with primary particle polydispersity (given constant geometric mean primary particle size pg). Here, m is taken as the projected area-equivalent diameter for the free molecular regime; Stokesian Dynamics is used to compute m in the continuum flow regime. For fixed number of primaries and pg, m increases with polydispersity in both free molecular and continuum regimes (>20% for large particles at high polydispersity). Considering an aerosol population with polydisperse primary particles, this increase is found to depend on whether the variations in primary particle size occur within aggregates or between aggregates; this can be important in the interpretation of measurements. Finally, mobility diameters are correlated with total number, median diameter and its geometric standard deviation of the primary particles.Applied Science, Faculty ofMechanical Engineering, Department ofReviewedFacultyGraduat