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Abstract Background The formation of secondary organic aerosols (SOA) by atmospheric oxidation reactions substantially contributes to the burden of fine particulate matter (PM2.5), which has been associated with adverse health effects (e.g., cardiovascular diseases). However, the molecular and cellular effects of atmospheric aging on aerosol toxicity have not been fully elucidated, especially in model systems that enable cell-to-cell signaling. Methods In this study, we aimed to elucidate the complexity of atmospheric aerosol toxicology by exposing a coculture model system consisting of an alveolar (A549) and an endothelial (EA.hy926) cell line seeded in a 3D orientation at the air‒liquid interface for 4 h to model aerosols. Simulation of atmospheric aging was performed on volatile biogenic (β-pinene) or anthropogenic (naphthalene) precursors of SOA condensing on soot particles. The similar physical properties for both SOA, but distinct differences in chemical composition (e.g., aromatic compounds, oxidation state, unsaturated carbonyls) enabled to determine specifically induced toxic effects of SOA. Results In A549 cells, exposure to naphthalene-derived SOA induced stress-related airway remodeling and an early type I immune response to a greater extent. Transcriptomic analysis of EA.hy926 cells not directly exposed to aerosol and integration with metabolome data indicated generalized systemic effects resulting from the activation of early response genes and the involvement of cardiovascular disease (CVD) -related pathways, such as the intracellular signal transduction pathway (PI3K/AKT) and pathways associated with endothelial dysfunction (iNOS; PDGF). Greater induction following anthropogenic SOA exposure might be causative for the observed secondary genotoxicity. Conclusion Our findings revealed that the specific effects of SOA on directly exposed epithelial cells are highly dependent on the chemical identity, whereas non directly exposed endothelial cells exhibit more generalized systemic effects with the activation of early stress response genes and the involvement of CVD-related pathways. However, a greater correlation was made between the exposure to the anthropogenic SOA compared to the biogenic SOA. In summary, our study highlights the importance of chemical aerosol composition and the use of cell systems with cell-to-cell interplay on toxicological outcomes. Graphical Abstract

Abstract Peatlands in the northern hemisphere are a major carbon storage but face an increased risk of wildfires due to climate change leading to large-scale smoldering fires in boreal and Arctic peatlands. Smoldering fires release organic carbon rich particulate matter, which influences the earth’s radiative balance and can cause adverse health effects for humans. Here we characterize the molecular composition of biomass burning particulate matter generated by laboratory burning experiments of peat by electrospray ionization 21 T Fourier-transform ion cyclotron resonance mass spectrometry, revealing a highly complex mixture of aromatic and aliphatic organic compounds with abundant heteroatoms including oxygen, sulfur and up to five nitrogen atoms. Primary organosulfur species are identified in the emissions of peat-smoldering, in part also containing nitrogen. Differences are observed when comparing structural motifs as well as the chemical composition of boreal and Arctic peat burning emissions, with the latter containing compounds with more nitrogen and sulfur.

Background: Successful rescue after elective surgery is associated with increased healthcare costs, but costs vary widely. Treating all rescue events the same may overlook targeted opportunities for improvement. The purpose of this study was to predict high-cost rescue after elective colorectal surgery. Methods: We identified adult patients in the National Inpatient Sample (2016–2021) who underwent elective colectomy or proctectomy. Rescued patients were defined as those who underwent additional major procedures. Three groups were stratified: 1) uneventful recovery; 2) Low-cost rescue; 3) High-cost rescue. Multivariable Poisson regression was used to identify preoperative clinical predictors of high-cost versus low-cost rescue. Results: We identified 448,590 elective surgeries, and rescued patients composed 4.8 %(21,635) of the total sample. The median increase in costs in rescued patients was $25,544(p

AlCrN and AlCrVYN thin films were deposited by physical vapor deposition using dcMS, HiPIMS and hybrid dcMS/HiPIMS processes. Although all the thin films were produced using the same time-average power and show only slight differences in the chemical composition, significant differences regarding their structure, morphology, and mechanical properties were identified. Both dcMS-AlCrN and dcMS-AlCrVYN thin films show a column-like structure of sharply defined grains with large crystallites having size of 168 nm and 133 nm and exhibit a low hardness of (6.7 ± 1.3) GPa and (8.9 ± 1.0) GPa, respectively. In contrast, HiPIMS thin films, despite their lower deposition rate (especially evident in HiPIMS-AlCrVYN, which exhibited the lowest deposition rate among all examined films), show a denser structure predominantly composed of fcc-CrN and, in the case of HiPIMS- and dcMS/HiPIMS-AlCrN, small amounts of hcp-AlN. Consequently, the HiPIMS-AlCrN and HiPIMS-AlCrVYN thin films showed higher hardness values of 28.0 ± 2.1 GPa and 30.7 ± 1.9 GPa, respectively. Combining the two methods by using one cathode in dcMS mode and one in HiPIMS mode results in films with similar hardness values (26.9 ± 1.6 GPa for AlCrN and 28.7 ± 2.2 GPa for AlCrVYN) and morphologies comparable to the pure HiPIMS thin films, but with an increase in the deposition rate. This demonstrates the advantage of combining the two methods, especially for the AlCrVYN thin film production. In comparison to AlCrN, the AlCrVYN thin films generally exhibit higher hardness demonstrating the advantage of adding larger atoms into the thin film structure.

Abstract Objectives To examine the military-civilian collaborative efforts which addressed the unprecedented challenges of the COVID-19 pandemic, particularly in areas including provision of supplies, patient and provider support, and development and dissemination of new vaccine and drug candidates. Methods We examined peer reviewed and grey literature from September 2020 to June 2021 to describe the relationship between the U.S. healthcare system and Military Health System (MHS). For analysis, we applied the World Health Organization framework for health systems, which consists of six building blocks. Results The strongest collaborative efforts occurred in areas of medicine and technology, human resources, and healthcare delivery, most notably in the MHS supplying providers, setting up treatment venues, and participating in development of vaccines and therapeutics. Highlighting that the MHS, with its centralized structure and ability to deploy assets rapidly, is an important contributor to the nation’s ability to provide a coordinated, large-scale response to health emergencies. Conclusions Continuing the relationship between the two health systems is vital to maintaining the nation’s capability to meet future health challenges.

# Background Latent trigger points have been identified as a source of impaired muscle function giving rise to a reduction in force production and alterations in muscle activation patterns and movement efficiency. There is limited investigation into the effectiveness of a treatment in reducing these clinical manifestations. # Purpose To investigate whether the application of trigger point dry needling (TDN) to latent trigger points within the gluteus medius musculature affected strength measurements and muscle activation levels immediately following intervention. # Design Quasi experimental, single group, pretest-posttest, randomized control study # Methods A control and an intervention side were randomly assigned for each participant (_N_ = 39). Hand held dynamometer (HHD) force measurements and raw surface electromyography (sEMG) amplitude readings were recorded during maximal volitional isometric contractions of the gluteus medius in two separate positions before and after application of TDN. Comparison of within and between group data were conducted. # Results A statistically significant interaction between time (pre-TDN to post-TDN) and groups (intervention side and control side), _p_ < 0.001 was found for HHD measurements in both positions. Post hoc analysis revealed a statistically significant difference (_p_ < 0.001) for all comparisons in the side lying neutral (SL0) position, while statistically significant differences (_p_ < 0.001) were found for pre and post-TDN measurements within intervention side as well as between the intervention and control side for post-TDN measurements in the side lying internal rotation (SLIR) position. For sEMG amplitude measurements, statistically significant differences were found only in the SL0 position for within group comparisons on the intervention side (_p_ = 0.009) and for between group comparisons for post-TDN measurements (_p_ = 0.002). # Conclusion Application of TDN to latent trigger points within the gluteus medius can significantly increase gluteus muscle force production immediately following intervention while reducing the level of muscle activation required during contraction. # Level of Evidence Level 2

The health effects of exposure to secondary organic aerosols (SOAs) are still limited. Here, we investigated and compared the toxicities of soot particles (SP) coated with β-pinene SOA (SOAβPin-SP) and SP coated with naphthalene SOA (SOANap-SP) in a human bronchial epithelial cell line (BEAS-2B) residing at the air–liquid interface. SOAβPin-SP mostly contained oxygenated aliphatic compounds from β-pinene photooxidation, whereas SOANap-SP contained a significant fraction of oxygenated aromatic products under similar conditions. Following exposure, genome-wide transcriptome responses showed an Nrf2 oxidative stress response, particularly for SOANap-SP. Other signaling pathways, such as redox signaling, inflammatory signaling, and the involvement of matrix metalloproteinase, were identified to have a stronger impact following exposure to SOANap-SP. SOANap-SP also induced a stronger genotoxicity response than that of SOAβPin-SP. This study elucidated the mechanisms that govern SOA toxicity and showed that, compared to SOAs derived from a typical biogenic precursor, SOAs from a typical anthropogenic precursor have higher toxicological potency, which was accompanied with the activation of varied cellular mechanisms, such as aryl hydrocarbon receptor. This can be attributed to the difference in chemical composition; specifically, the aromatic compounds in the naphthalene-derived SOA had higher cytotoxic potential than that of the β-pinene-derived SOA.

While it is well known that wildfires can greatly contribute to soil water repellency by changing soil chemical composition, the mechanisms of these changes are still poorly understood. In the past decade, the number, size, and intensity of wildfires have greatly increased in the western USA. Recent megafires in California (i.e., the Dixie, Beckwourth Complex, Caldor, and Mosquito fires) provided us with an opportunity to characterize pre- and post-fire soils and to study the effects of fires on soil water repellency, soil organic constituents, and connections between the two. Water drop penetration time (WDPT) tests performed in the field showed a significant increase (from 600 s) in WDPT from pre- to post-fire soils. This increase in soil water repellency after fires was confirmed by increases in apparent contact angle (ACA) between 1.1 and 9 times from unburned to burned soils. The chemical characterization of burned soils with high resolution mass spectrometry showed the increased abundance of hydrophobic organics (e.g., PAH-like compounds and organic molecules with a low number of oxygen atoms) as well as the correlation of the average H/C ratio and aromaticity index (AI) with ACA. Most likely, these compounds contribute to post-fire soil water repellency that triggers hydrological effects such as landslides, flooding, and debris flows.