Aim: To assess the effect of air, gas mixture composed of 50% nitrogen and 50% oxygen (nitrox 50), or gas mixture composed of 1% nitrogen and 99% oxygen (nitrox 99) on bubble formation and vascular/endothelial function during decompression after self-contained underwater breathing apparatus diving.
Methods: This randomized controlled study, conducted in 2014, involved ten divers. Each diver performed three dives in a randomized protocol using three gases: air, nitrox 50, or nitrox 99 during ascent. The dives were performed on three different days limited to 45 m sea water (msw) depth with 20 min bottom time. Nitrogen bubbles formation was assessed by ultrasound detection after dive. Arterial/endothelial function was evaluated by brachial artery flow mediated dilatation (FMD) before and after dive.
Results: Nitrox 99 significantly reduced bubble formation after cough compared with air and nitrox 50 (grade 1 vs 3 and vs 3, respectively, P=0.026). Nitrox 50 significantly decreased post-dive FMD compared with pre-dive FMD (3.62 ± 5.57% vs 12.11 ± 6.82% P=0.010), while nitrox 99 did not cause any significant change.
Conclusion: Nitrox 99 reduced bubble formation, did not change post-dive FMD, and decreased total dive duration, indicating that it might better preserve endothelial function compared with air and nitrox 50 dive protocols.
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http://dx.doi.org/10.3325/cmj.2019.60.265 | DOI Listing |
Sci Rep
December 2024
Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.
Polymer electrolyte membrane water electrolyzers (PEMWEs) are a critical technology for efficient hydrogen production to decarbonize fuels and industrial feedstocks. To make hydrogen cost-effective, the overpotentials across the cell need to be decreased and platinum-group metal loading reduced. One overpotential that needs to be better understood is due to mass transport limitations from bubble formation within the porous transport layer (PTL) and anode catalyst layer (ACL), which can lead to a reduction in performance at typical operating current densities.
View Article and Find Full Text PDFParasit Vectors
December 2024
State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, 130062, China.
Background: Echinococcosis is a zoonotic disease caused by an Echinococcus tapeworm infection. While diagnostic methods for humans often rely on ultrasound imaging and immunodiagnostic techniques, diagnosis in intermediate hosts typically has no widely used diagnostic markers, hampering disease control efforts.
Methods: The differences in serum metabolites of sheep infected with Echinococcus granulosus and a control group were analyzed using ultrahigh-performance liquid chromatography (UHPLC) separation with tandem mass spectrometry (MS/MS) detection.
Sci Rep
December 2024
Department of Pharmaceutical Chemistry, Dr. D. Y. Patil Institute of Pharmaceutical Sciences and Research, Pimpri, Pune, India.
The emergence of self-propelling magnetic nanobots represents a significant advancement in the field of drug delivery. These magneto-nanobots offer precise control over drug targeting and possess the capability to navigate deep into tumor tissues, thereby addressing multiple challenges associated with conventional cancer therapies. Here, Fe-GSH-Protein-Dox, a novel self-propelling magnetic nanobot conjugated with a biocompatible protein surface and loaded with doxorubicin for the treatment of triple-negative breast cancer (TNBC), is reported.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Italy.
Hypothesis: Bubbles oscillating near a free surface are common across numerous systems. Thin liquid films (TLFs) formed between an oscillating bubble and a free surface can exhibit distinct morphological features influenced by interfacial properties, evaporation, and deformation history. We hypothesize that a continuous film presence throughout oscillation results in a wimple morphology, whereas intermittent film presence leads to a dimple formation.
View Article and Find Full Text PDFLangmuir
December 2024
School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China.
This study explores the bubble nucleation process and heat transfer characteristics on nanostructured solid surfaces with mixed-wettable pillars using molecular dynamics simulations. Five different surfaces were designed by varying the wettability of the central pillars while keeping the lateral pillars hydrophilic. The nucleation behavior of argon bubbles was observed to differ significantly across these surfaces due to the combined effects of nanostructuring and mixed wettability.
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