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The widespread COVID-19 pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) necessitated measures aimed at preventing the spread of SARS-CoV-2. To mitigate the risk of fomite-mediated transmission, environmental cleaning and disinfection regimes have been widely implemented. However, conventional cleaning approaches such as surface wipe downs can be laborious and more efficient and effective disinfecting technologies are needed. Gaseous ozone disinfection is one technology which has been shown to be effective in laboratory studies. Here, we evaluated its efficacy and feasibility in a public bus setting, using murine hepatitis virus (a related betacoronavirus surrogate) and the bacteria Staphylococcus aureus as test organisms. An optimal gaseous ozone regime resulted in a 3.65-log reduction of murine hepatitis virus and a 4.73-log reduction of S. aureus, and decontamination efficacy correlated with exposure duration and relative humidity in the application space. These findings demonstrated gaseous ozone disinfection in field settings which can be suitably translated to public and private fleets that share analogous characteristics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Introduction: With the emergence of artificial intelligence (AI) in medical imaging, radiographers are likely to be at the forefront of this technological advancement. Studies have therefore been conducted recently to understand radiographers' opinions on AI adoption. This study extends that work by using a qualitative approach to further explore radiographers' knowledge, perceptions, and expectations of AI., Method: Six online focus groups were conducted with 22 radiographers from the three public healthcare clusters in Singapore. They were purposively sampled, and participants were recruited from a broad demographic background with varying years of working experience and designations. The focus group sessions were transcribed verbatim and thematic analysis was performed on their responses., Results: Participants demonstrated limited knowledge of AI. Their perceptions of AI were mixed, recognising its benefits in increasing efficiency and improving patient care, but also aware of its limitations in accuracy and bias. On how patients may perceive AI, participants felt that patients would accept AI if they felt it improves their care but may reject it once they lose trust in it. Expectations wise, participants envisioned several applications in pre-, peri‑, and post-procedural workflows including order vetting, patient positioning, language translation, and artefact removal. On radiographers' role and career opportunities, some participants see an opportunity for radiographers to specialise in AI, becoming involved in algorithm development and its clinical implementation., Discussion: Our findings suggest that widespread implementation of AI would require limited knowledge amongst radiographers and current AI limitations to be addressed. While radiographers are positively anticipating the integration of AI into their practices, they should also become actively involved in the development of AI tools such that those they envisioned. This would help align optimal use of AI tools and radiographer role changes. Patients' acceptance and reactions to AI also warrant further research., (Copyright © 2022. Published by Elsevier Inc.)

Cellular models exhibiting human physiological features of pseudostratified columnar epithelia, provide a more realistic approach for elucidating detailed mechanisms underlying PM 2.5 -induced pulmonary toxicity. In this study, we characterized the barrier and mucociliary functions of differentiated human small airway epithelial cells (SAECs), cultured at the air-liquid interface (ALI). Due to the presence of mucociliary protection, particle internalization was reduced, with a concomitant decrease in cytotoxicity in differentiated S-ALI cells, as compared to conventional submerged SAEC cultures. After 24-hour exposure to PM 2.5 surrogates, 117 up-regulated genes and 156 down-regulated genes were detected in S-ALI cells, through transcriptomic analysis using the Affymetrix Clariom™ S Human Array. Transcription-level changes in >60 signaling pathways, were revealed by functional annotation of the 273 differentially expressed genes, using the PANTHER Gene List Analysis. These pathways are involved in multiple cellular processes, that include inflammation and apoptosis. Exposure to urban PM 2.5 led to complex responses in airway epithelia, including a net induction of downstream pro-inflammatory and pro-apoptotic responses. Collectively, this study highlights the importance of using the more advanced ALI model rather than the undifferentiated submerged model, to avoid over-assessment of inhaled particle toxicity in human. The results of our study also suggest that reduction of ambient PM 2.5 concentrations would have a protective effect on respiratory health in humans., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Adverse health effects arising from exposure to fine particulates have become a major concern. Angiogenesis is a vital physiological process for the growth and development of cells and structures in the human body, whereby excessive or insufficient vessel growth could contribute to pathogenesis of diseases. We therefore evaluated indirect effects of carbon black (CB) and inhalable airborne particles on the angiogenic ability of unexposed Human Umbilical Vein Endothelial Cells (HUVECs) by co-culturing HUVECs with pre-exposed Small Airway Epithelial Cells (SAECs). As endothelial cells are major components of blood vessels and potential targets of fine particles, we investigated if lung epithelial cells exposed to ambient PM 2.5 surrogates could induce bystander effects on neighboring unexposed endothelial cells in an alveolar-capillary co-culture lung model. Epithelial exposure to CB at a non-toxic dose of 25 μg/mL reduced endothelial tube formation and cell adhesion in co-cultured HUVECs, and decreased expression of angiogenic genes in SAECs. Similarly, exposure of differentiated SAECs to PM 2.5 surrogates reduced cell reproductive ability, adhesion and tube formation of neighboring HUVECs. This indicates epithelial exposure to CB and urban PM 2.5 surrogates both compromised the angiogenic ability of endothelial cells through bystander effects, thereby potentially perturbing the ventilation-perfusion ratio and affecting lung function., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The quantification of canopy photosynthesis and evapotranspiration of crops (ET c ) is essential to appreciate the effects of environmental changes on CO 2 flux and water availability in agricultural ecosystems and crop productivity. This study simulated the canopy photosynthesis and ET processes of paddy rice (Oryza sativa) based on the development of physiological modules (i.e., gross primary production [GPP] and ET c ) and their incorporation into the GRAMI-rice model that uses remote sensing data. We also projected spatiotemporal variations in the GPP, ET, yield, and biomass of paddy rice at maturity using the updated GRAMI-rice model combined with geostationary satellite images to identify the relationships of canopy photosynthesis and ET c with crop productivity. GPP and ET data for paddy rice were obtained from three KoFlux sites in South Korea in 2015 and 2016. Vegetation indices were acquired from the Geostationary Ocean Color Imager (GOCI) of the Communication Ocean and Meteorological Satellite (COMS) from 2012 to 2017 and integrated into GRAMI-rice. GPP and ET c estimates using GRAMI-rice were in close agreement with flux tower estimates with Nash-Sutcliffe efficiency ranges of 0.40-0.79 for GPP and 0.49-0.62 for ET c . Also, GRAMI-rice was reasonably well incorporated with the COMS GOCI imagery and reproduced spatiotemporal variations in the GPP and ET of rice in the Korean peninsula. The current study results demonstrate that the updated GRAMI-rice model with the canopy photosynthesis and ET c modules is capable of reproducing spatiotemporal variations in CO 2 assimilation and ET of paddy rice at various geographical scales and for regions of interest that are observable by satellite sensors (e.g., inaccessible North Korea)., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Gold nanoparticles (AuNPs) have emerging applications in biomedicine and the industry. Exposure to AuNPs has previously been shown to alter the transcriptional activity of nuclear factor kappa B (NF-kB), which is known to mediate physiological and pathological processes. This study seeks to provide mechanistic insights into AuNP-induced NF-kB activation in Small Airway Epithelial Cells (SAECs) in vitro. Increased NF-kB transcriptional activity (quantified by the luciferase reporter assay) was observed in AuNP-treated SAECs. Transcriptomic analysis revealed differential expression of 42 genes, which regulate functional processes that include cellular response to stimulus, chemicals and stress as well as immune response. Notably, the gene expression of serum amyloid A1 (SAA1), an acute phase protein and Toll-like receptor 2 (TLR2) were found to be up-regulated. As TLR2 is known to be a functional receptor of SAA1, a co-immunoprecipitation assay was performed. SAA1 was observed to be co-immunoprecipitated with the TLR2 protein and this protein-protein interaction was further supported by in silico computer based protein modeling. The present study suggests that AuNPs may potentially induce SAA1-TLR2-mediated NF-kB transcription factor activation in lung epithelial cells, highlighting that nano-bio interactions could result in biological effects that may affect cells., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A 57-year-old man was incidentally found to have a dissected diverticulum of Kommerell originating from aberrant origin of right subclavian artery during follow-up for treated colon cancer. A right carotid-axillary bypass was followed by embolization of aberrant artery and the diverticulum by deployment of multiple detachable coils using the Penumbra Ruby System (Penumbra, Alameda, CA). Angiography after embolization showed exclusion of flow to the aberrant artery and a patent right carotid-axillary bypass. The patient recovered uneventfully and remained well for 12 weeks after the operation, without any complications. We believe this targeted endovascular approach can avoid complications related to the coverage of thoracic aorta and reduce the risk of access vessel trauma., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Urban roughness is a major factor governing the flows and scalar transport in the atmospheric boundary layer (ABL) but our understanding is rather limited. The ventilation and pollutant removal of hypothetical urban areas consisting of various types of street canyons are examined using computational fluid dynamics (CFD). The aerodynamic resistance, ventilation efficiency, and pollutant removal are measured by the friction factor f, air exchange rate (ACH), and pollutant exchange rate (PCH), respectively. Two source configurations of passive tracer, ground-level-only (Tracer 0) and all-solid-boundary (Tracer 1) are employed to contrast their transport behavior. It is found that the ventilation and pollutant removal are largely attributed to their turbulent components (over 60%). Moreover, with a consistent support from analytical solution and CFD results, the turbulent ACH is a linear function of the square root of the friction factor (ACH'∝f(1/2)) regardless of building geometry. Tracer 0 and Tracer 1 exhibit diversified removal behavior as functions of friction factor so analytical parameterizations have not yet been developed. In view of the large portion of aged air removal by turbulence, it is proposed that the aerodynamic resistance can serve as an estimate to the minimum ventilation efficiency of urban areas., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Although expression quantitative trait locus, eQTL, serves as an explicit indicator of gene-gene associations, challenges remain to disentangle the mechanisms by which genetic variations alter gene expression. Here we combined eQTL and molecular analyses to identify an association between two seemingly non-associated genes in brain expression data from BXD inbred mice, namely Ptpn21 and Nrg3. Using biotinylated receptor tracking and immunoprecipitation analyses, we determined that PTPN21 de-phosphorylates the upstream receptor tyrosine kinase ErbB4 leading to the up-regulation of its downstream signaling. Conversely, kinase-dead ErbB4 (K751R) or phosphatase-dead PTPN21 (C1108S) mutants impede PTPN21-dependent signaling. Furthermore, PTPN21 also induced Elk-1 activation in embryonic cortical neurons and a novel Elk-1 binding motif was identified in a region located 1919bp upstream of the NRG3 initiation codon. This enables PTPN21 to promote NRG3 expression through Elk-1, which provides a biochemical mechanism for the PTPN21-NRG3 association identified by eQTL. Biologically, PTPN21 positively influences cortical neuronal survival and, similar to Elk-1, it also enhances neuritic length. Our combined approaches show for the first time, a link between NRG3 and PTPN21 within a signaling cascade. This may explain why these two seemingly unrelated genes have previously been identified as risk genes for schizophrenia., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Viruses must modulate or suppress their host's immune system in order to persist. In this review, we discuss the means in which the lympocytic choriomenengitis virus targets and infects an essential component of the immune system, the dendritic cell, essential to bridging the innate and adaptive immune response. Infection of these cells results in pleiotropic effects that serve to deregulate the host immune response.

The solubility parameters of a range of saturated hydrocarbons were calculated from vapor pressures and heats of vaporization. Solubilities of testosterone propionate were determined in these solvents at 25 degrees and yielded solute solubility parameters which varied from solvent to solvent. The solubility parameter of testosterone propionate was determined by several other methods, and support was found for the previously published figure of 9.5 cal(1/2) cm(-3/2). The geometric mean coefficient (l(12)) in saturated hydrocarbons was found to be a rectilinear function of the branching ratio (r). The mean l(12) of androstanolone and testosterone propionates was used to calculate the solubilities of other esters, giving good agreement with experimental results. IR data, presented as the sum of the shifts of the 3-keto and 17-ester carbonyl stretching frequencies in polar solvents, correlated rectilinearly with the geometric mean coefficients and the plot extrapolated to the l(12) value of n-hexane, calculated from the branching ratio plot. Attempts to predict solubilities of other esters in polar solvents using l(12) values achieved only limited success.