Orthogonal Reference Surrogate Fuels for Operability Testing

The approval and evaluation process for sustainable aviation fuels (SAF) via ASTM D4054 is both cost- and volume-intensive, namely due to engine operability testing under severe conditions. Engine operability tests of combustor under figures of merit (FOM) limit phenomena are the fuel effects on lean blowout, high-altitude relight, and cold-start ignition. One method to increase confidence and reduce volume in tiered testing is to use surrogate fuels for manipulation of properties. Key fuel performance properties (surface tension, viscosity, density) for cold-start ignition was determined prior to this study. Prior work regarding this FOM has not considered the combination of these properties. A surface tension blending rule was validated and incorporated into the jet fuel blend optimizer (JudO). A generalized surrogate calculator for N-dimensional surrogate components and features was developed. Jet fuel surrogates developed in this study were a mixture of conventional and sustainable aviation fuels instead of pure components. These surrogates suggested to be tested in this study could illuminate near worst-case effects for sustainable aviation fuel in a given configuration/rig. With those scenarios tested, we can further understand the influence on the key properties relative to cold-start ignition. This work and supporting experimental evidence could potentially lower the barrier for SAF approval processes. Document type: Articl

Utility of Two-Stage Laryngotracheal Reconstruction in the Management of Subglottic Stenosis in Adults

No abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/83473/1/21521_ftp.pd

Global phylogeography and ancient evolution of the widespread human gut virus crAssphage

Microbiomes are vast communities of microorganisms and viruses that populate all natural ecosystems. Viruses have been considered to be the most variable component of microbiomes, as supported by virome surveys and examples of high genomic mosaicism. However, recent evidence suggests that the human gut virome is remarkably stable compared with that of other environments. Here, we investigate the origin, evolution and epidemiology of crAssphage, a widespread human gut virus. Through a global collaboration, we obtained DNA sequences of crAssphage from more than one-third of the world's countries and showed that the phylogeography of crAssphage is locally clustered within countries, cities and individuals. We also found fully colinear crAssphage-like genomes in both Old-World and New-World primates, suggesting that the association of crAssphage with primates may be millions of years old. Finally, by exploiting a large cohort of more than 1,000 individuals, we tested whether crAssphage is associated with bacterial taxonomic groups of the gut microbiome, diverse human health parameters and a wide range of dietary factors. We identified strong correlations with different clades of bacteria that are related to Bacteroidetes and weak associations with several diet categories, but no significant association with health or disease. We conclude that crAssphage is a benign cosmopolitan virus that may have coevolved with the human lineage and is an integral part of the normal human gut virome

Global phylogeography and ancient evolution of the widespread human gut virus crAssphage

Microbiomes are vast communities of microorganisms and viruses that populate all natural ecosystems. Viruses have been considered to be the most variable component of microbiomes, as supported by virome surveys and examples of high genomic mosaicism. However, recent evidence suggests that the human gut virome is remarkably stable compared with that of other environments. Here, we investigate the origin, evolution and epidemiology of crAssphage, a widespread human gut virus. Through a global collaboration, we obtained DNA sequences of crAssphage from more than one-third of the world’s countries and showed that the phylogeography of crAssphage is locally clustered within countries, cities and individuals. We also found fully colinear crAssphage-like genomes in both Old-World and New-World primates, suggesting that the association of crAssphage with primates may be millions of years old. Finally, by exploiting a large cohort of more than 1,000 individuals, we tested whether crAssphage is associated with bacterial taxonomic groups of the gut microbiome, diverse human health parameters and a wide range of dietary factors. We identified strong correlations with different clades of bacteria that are related to Bacteroidetes and weak associations with several diet categories, but no significant association with health or disease. We conclude that crAssphage is a benign cosmopolitan virus that may have coevolved with the human lineage and is an integral part of the normal human gut virome

International Consensus Statement on Rhinology and Allergy: Rhinosinusitis

Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR‐RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR‐RS‐2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence‐based findings of the document. Methods: ICAR‐RS presents over 180 topics in the forms of evidence‐based reviews with recommendations (EBRRs), evidence‐based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICAR‐RS‐2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence‐based management algorithm is provided. Conclusion: This ICAR‐RS‐2021 executive summary provides a compilation of the evidence‐based recommendations for medical and surgical treatment of the most common forms of RS

Comorbidities of asthma and the unified airway

BACKGROUND: Asthma is a comorbid condition that may be seen by otolaryngic allergists when treating their patients with allergic rhinitis (AR). Often asthma is overlooked when aggressive treatment could prevent the development or progression of early disease. METHODS: This article is a retrospective review of the current literature on asthma as a comorbidity of the unified airway. The unified airway and asthma are clearly defined. The epidemiology, morbidity, mortality, pathophysiologic mechanisms, and the chronicity of asthma are reviewed. RESULTS: The otolaryngic allergist will become familiar the unified airway concept and the close relationships between AR, chronic rhinosinusitis, and asthma. CONCLUSION: Otolaryngologists should be aware of the unified airway in order to most effectively treat their patients with AR. Knowledge of the close relationships between asthma and AR will help prevent progression of disease, identify early asthma, and improve the outcomes and quality of life for our patients

Orthogonal Reference Surrogate Fuels for Operability Testing

The approval and evaluation process for sustainable aviation fuels (SAF) via ASTM D4054 is both cost- and volume-intensive, namely due to engine operability testing under severe conditions. Engine operability tests of combustor under figures of merit (FOM) limit phenomena are the fuel effects on lean blowout, high-altitude relight, and cold-start ignition. One method to increase confidence and reduce volume in tiered testing is to use surrogate fuels for manipulation of properties. Key fuel performance properties (surface tension, viscosity, density) for cold-start ignition was determined prior to this study. Prior work regarding this FOM has not considered the combination of these properties. A surface tension blending rule was validated and incorporated into the jet fuel blend optimizer (JudO). A generalized surrogate calculator for N-dimensional surrogate components and features was developed. Jet fuel surrogates developed in this study were a mixture of conventional and sustainable aviation fuels instead of pure components. These surrogates suggested to be tested in this study could illuminate near worst-case effects for sustainable aviation fuel in a given configuration/rig. With those scenarios tested, we can further understand the influence on the key properties relative to cold-start ignition. This work and supporting experimental evidence could potentially lower the barrier for SAF approval processes

More on the Role of the Mandible in Speech Production: Clinical Correlates of Green, Moore, and Reilly’s (2002) Findings \u3ci\u3eAND\u3c/i\u3e Methodological Issues in Studies of Early Articulatory Development: A Response to Dworkin, Meleca, and Stachler (2003)

Dworkin et al. comment: We would like to comment on Green, Moore, and Reilly’s article, which appeared in the February 2002 issue of this journal [Journal of Speech, Language, and Hearing Research]. In that investigation, these clinical researchers examined upper lip, lower lip, and mandibular movements during repetitive bisyllable word productions by infants, toddlers, young children, and adults with normal developmental and neurologic histories. Kinematic traces from these articulators were analyzed using a computer-based movement tracking system. Results revealed that these oral structures may have sequential neuromotor developmental schedules, characterized by more mature movement patterns for speech emerging earlier in the mandible than in either the upper or lower lip. That is, that normal speech development involves the integration of lip and tongue activities into a more well-established, biomechanically dominant jaw operating sensorimotor system. To facilitate our response to this investigation, we have chosen first to extend the results by elaborating on the causally related role of the mandible in certain speech disordered populations, and second, to highlight how adjunctive methods of data collection may have strengthened the validity of the overall findings. Green et al. respond: We appreciate the opportunity to clarify our previous findings in response to questions raised by Dworkin, Meleca, and Stachler (2003), who have cited our work with respect to its implications for the study and treatment of speech motor impairment. These researchers raise the possibility that differences in articulatory performance across the age groups may have been related to group differences in speech sampling methods rather than to development. They imply that because our younger (i.e., 1- or 2-years-old) participants’ utterances were obtained with reduced experimental control relative to the older participants’ (play vs. reading), their articulatory performance should have been less consistent than the older participants’ because of naturally occurring variations in loudness and rate, and potential “upstream” effects related to “torso and limb adjustments.” Several aspects of our experimental design mitigate these concerns and, most importantly, our findings are the opposite of predicted effects arising from speech sampling differences across age groups: (a)Adult-like stability was observed in the infants’ jaw movement patterns despite the fact that infant vocalizations were elicited under less controlled conditions. (b) Each participant served as his or her own control, which permitted the evaluation of differences across articulators during development. (c) Postprocessing techniques minimized linear-scaling differences in articulatory movement across repetitions. (d) Finally, trunk mobility was restricted during data collection