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The NOAA Vents program was established in 1983 at the Pacific Marine Environmental Laboratory (PMEL; Hammond et al., 2015), just six years after the discovery of hydrothermal vents and their unique chemosynthetic ecosystems (Corliss et al., 1979). Because seafloor hydrothermal venting contributes significantly to the transfer of heat and mass from the solid Earth to the ocean, the program’s mission was to systematically explore, discover, and characterize the environmental impacts of submarine volcanism and hydrothermal venting on ocean physical, chemical, and biological processes. The program initially focused on the mid-ocean spreading centers in PMEL’s “backyard” (i.e., the Gorda, Juan de Fuca, and Endeavour Ridges in the Northeast Pacific) where segment-scale surveys detected plumes in the water column above the ridge crest that led to the discovery of numerous individual vent fields (see Hammond et al., 2015, and references therein). New technologies and techniques were created and/or adapted to address the challenges of finding and studying these vents. Repeat visits to the Northeast Pacific sites documented spatial and temporal changes, stimulating the development of new hypotheses about their associated biogeochemical processes. However, testing how broadly applicable these hypotheses would be on a global scale required discovering new vent sites from a far wider range of geological settings, and global-scale exploration requires significant resources.

The Coronavirus Disease 2019 (COVID-19) pandemic renewed interest in infectious aerosols and reducing risk of airborne respiratory pathogen transmission, prompting development of devices to protect healthcare workers during airway procedures. However, there are no standard methods for assessing the efficacy of particle containment with these protective devices. We designed and built an aerosol bio-containment device (ABCD) to contain and remove aerosol via an external suction system and tested the aerosol containment of the device in an environmental chamber using a novel, quantitative assessment method. The ABCD exhibited a strong ability to control aerosol exposure in experimental and computational fluid dynamic (CFD) simulated scenarios with appropriate suction use and maintenance of device seals. Using a log-risk-reduction framework, we assessed device containment efficacy and showed that, when combined with other protective equipment, the ABCD can significantly reduce airborne clinical exposure. We propose this type of quantitative analysis serves as a basis for rating efficacy of aerosol protective enclosures.

Xylella fastidiosa is a multi-continental, lethal, plant pathogenic bacterium that is transmitted by sharpshooter leafhoppers (Insecta: Hemiptera: Cicadellidae: Cicadellinae) and adult spittlebugs (Hemiptera: Aphrophoridae). The bacterium forms biofilms in plant xylem and the functional foregut of the insect. These biofilms serve as sources of inoculum for insect acquisition and subsequent inoculation to a healthy plant. In this study, 3D fluid dynamic simulations were performed for bidirectional cibarial propulsion of xylem sap through tube-like grapevine xylem and an anatomically accurate model of the functional foregut of the blue-green sharpshooter, Graphocephala atropunctata . The analysis supports a model of how fluid dynamics influence X . fastidiosa transmission. The model supports the hypothesis that X . fastidiosa inoculation is mostly driven by detachment of bacteria from the foregut due to high-velocity flow during egestion (outward fluid flow from the stylets). Acquisition occurs by fluid dynamics during both egestion and ingestion (fluid uptake through the stylets and swallowing). These simulation results are supported by previously reported X . fastidiosa colonization patterns in the functional foregut and sharpshooter stylet probing behaviors. The model indicates that xylem vessel diameter influences drag forces imposed on xylem wall-adherent bacteria; thus, vessel diameter may be an important component of the complex transmission process. Results from this study are directly applicable to development of novel grapevine resistance traits via electropenetrographic monitoring of vector acquisition and inoculation behaviors.

Based on previously published hydroponic plant, planktonic bacterial, and soil microbial community research, manufactured nanomaterial (MNM) environmental buildup could profoundly alter soil-based food crop quality and yield. However, thus far, no single study has at once examined the full implications, as no studies have involved growing plants to full maturity in MNM-contaminated field soil. We have done so for soybean, a major global commodity crop, using farm soil amended with two high-production metal oxide MNMs (nano-CeO ₂ and -ZnO). The results provide a clear, but unfortunate, view of what could arise over the long term: (i) for nano-ZnO, component metal was taken up and distributed throughout edible plant tissues; (ii) for nano-CeO ₂, plant growth and yield diminished, but also (iii) nitrogen fixation—a major ecosystem service of leguminous crops—was shut down at high nano-CeO ₂ concentration. Juxtaposed against widespread land application of wastewater treatment biosolids to food crops, these findings forewarn of agriculturally associated human and environmental risks from the accelerating use of MNMs.

The powerful eruption of Hunga volcano (15‐January‐2022) excavated ∼6.3 km3 of pre‐existing material, leaving behind an 855 m deep crater. The scientific and humanitarian response to this event was challenging due to the remote location, safety concerns, and COVID‐19 pandemic restrictions. To investigate the status of ongoing eruptive/hydrothermal activity, this study used, for the first time, an un‐crewed surface vessel operated remotely from >16,000 km away to make direct water column measurements within the crater and map its structure in detail. Intense turbidity and oxidation‐reduction potential (ORP) anomalies located ongoing activity at sites on the steep inside crater slopes near both remaining islands. Mid‐water acoustic reflectors indicated ongoing degassing, and positive ORP anomalies suggested gas composition was dominated by CO2. At least 75% of the crater rim is shallower than 100 m, so any exchange with the surrounding ocean is limited by the depths of breaches in the rim (185 m between the islands and 290 m on the ENE side). This post‐eruption bathymetry results in accumulation of emission products within the deep crater. There were no indications of the ongoing activity visible at the ocean surface, which highlights the limitations and inherent biases associated with relying on discolored surface water and/or atmospheric disturbances to determine eruption start/end dates at submarine volcanoes. This study demonstrates the value and need to add repeat hydrothermal plume and bathymetric surveys to our toolbox for monitoring submarine volcanoes, and the potential for un‐crewed, remotely operated vessels to contribute significantly to these efforts. Plain Language Summary The powerful eruption of Hunga volcano on 15‐January‐2022 sent a plume to space and generated unusual tsunamis. How the eruption impacted the submarine environment was more difficult to determine. We used a highly innovative, un‐crewed vessel equipped with instruments to directly measure characteristics of the water within the 850 m deep crater excavated during the eruption and map the crater's shape in detail. These measurements showed there was ongoing hydrothermal/volcanic activity and CO2 degassing within the crater 7 months after the eruption. The deepest parts of the crater are isolated from the surrounding ocean, so products of this activity become trapped within the crater. While the most powerful eruptions are rare, they can be quite hazardous. The results from this study emphasize the importance of monitoring submarine volcanoes long after signs of eruptions are no longer visible at the ocean surface or atmosphere. Operation of the un‐crewed vessel >16,000 km from the study site was a major technological achievement and the first time that scientists could monitor operations in real time from anywhere around the globe. The success of this mission demonstrated the potential of this innovative technology to contribute to broader applications in ocean exploration, monitoring, and event response. Key Points Hydrothermal/volcanic activity and CO2 degassing continued at Hunga volcano 7 months after the explosive 15 January 2022 eruption Turbidity and CO2 are accumulating within the deep crater, which is isolated from the surrounding ocean deeper than ∼200 m First use of a novel un‐crewed vessel to conduct over‐the‐horizon bathymetric and water column surveys operated >16,000 km from the study site

In addition to high‐temperature vents, lower‐temperature flow (LTF) (<300°C) is abundant along mid‐ocean ridges and contributes globally‐important fluxes of heat and water along with largely‐unconstrained geochemical influences on the ocean. We examined the impact of on‐axis LTF on the chemical composition of the overlying water column (<40 m above seafloor) along the 16.5°–18.0°S sector of the ultrafast‐spreading southern East Pacific Rise using autonomous underwater vehicle Sentry surveys and conductivity‐temperature‐depth rosette casts. LTF sites were typically spatially isolated from high‐temperature systems and imparted unique chemical signatures to the overlying ocean. Water column samples impacted by LTF exhibited low particulate iron:sulfur ratios and high methane: total‐dissolvable manganese ratios, whereas samples influenced by high‐temperature venting exhibited opposite trends. We confirmed that LTF imparts a distinct and measurable chemical signature to the water column, independent from high‐temperature vents. Isolated, on‐axis LTF will be important to consider when assessing hydrothermal circulation impacts upon ocean biogeochemistry.

Efficient photocatalytic disinfection of Escherichia coli O157:H7 was achieved by using a C 70 modified TiO 2 (C 70 -TiO 2 ) hybrid as a photocatalyst under visible light (λ > 420 nm) irradiation. Disinfection experiments showed that 73% of E. coli O157:H7 died within 2 h with a disinfection rate constant of k  = 0.01 min −1 , which is three times that measured for TiO 2 . The mechanism of cell death was investigated by using several scavengers combined with a partition system. The results revealed that diffusing hydroxyl radicals play an important role in the photocatalytically initiated bacterial death and direct contact between C 70 -TiO 2 hybrid and bacteria is not indispensable in the photocatalytic disinfection process. Extracellular polymeric substances (EPS) of bacteria have little effect on the disinfection efficiency. Analyses of the inhibitory effect of C 70 -TiO 2 thin films on E. coli O157:H7 showed a decrease of the bacterial concentration from 3 × 10 8 to 38 cfu mL −1 in the solution with C 70 -TiO 2 thin film in the first 2 h of irradiation and a complete inhibition of the growth of E. coli O157:H7 in the later 24 h irradiation.

Clay minerals and metal oxides, as important parts of the soil matrix, play crucial roles in the development of microbial communities. However, the mechanism underlying such a process, particularly on the formation of soil biofilm, remains poorly understood. Here, we investigated the effects of montmorillonite, kaolinite, and goethite on the biofilm formation of the representative soil bacteria Bacillus subtilis . The bacterial biofilm formation in goethite was found to be impaired in the initial 24 h but burst at 48 h in the liquid–air interface. Confocal laser scanning microscopy showed that the biofilm biomass in goethite was 3–16 times that of the control, montmorillonite, and kaolinite at 48 h. Live/Dead staining showed that cells had the highest death rate of 60% after 4 h of contact with goethite, followed by kaolinite and montmorillonite. Atomic force microscopy showed that the interaction between goethite and bacteria may injure bacterial cells by puncturing cell wall, leading to the swarming of bacteria toward the liquid–air interface. Additionally, the expressions of abrB and sinR , key players in regulating the biofilm formation, were upregulated at 24 h and downregulated at 48 h in goethite, indicating the initial adaptation of the cells to minerals. A model was proposed to describe the effects of goethite on the biofilm formation. Our findings may facilitate a better understanding of the roles of soil clays in biofilm development and the manipulation of bacterial compositions through controlling the biofilm in soils. Soil: Mineral effects on biofilms The effect of three soil minerals on biofilm production is clarified by research using the common soil bacterium Bacillus subtilis . The mineral composition of soil is known to affect biofilm production, but the mechanisms underpinning minerals’ influences have not been well studied. Peng Cai and colleagues at Huazhong Agricultural University in China, with co-workers in the United States and Singapore, studied Bacillus subtilis growing in the presence of the minerals montmorillonite, kaolinite, and goethite. Their results suggest the minerals, especially goethite, can encourage biofilm formation by promoting the bursting of bacterial cells. The effect of goethite was attributed to the size of its grains being generally smaller than the bacterial cells. By quantifying the effect of these minerals, the research will assist understanding of biofilm formation and the growth and persistence of bacterial populations in soils.

As previously summarized by Hammond et al. (2015), from 1983 to 2013, the NOAA Vents program conducted systematic and multidisciplinary exploration, discovery, and research related to hydrothermal vents, submarine volcanic eruptions, and associated ocean physical, chemical, and biological processes. In 2014, Vents divided into two programs, Earth-Ocean Interactions (EOI) and Acoustics, and considered a broader range of questions about how seafloor and subseafloor processes contribute to ocean health, biogeochemical cycles, ecosystem diversity, and climate change. Here, we highlight major accomplishments since 2014, including deep-sea technologies that EOI, Vents, and Pacific Marine Environmental Laboratory (PMEL) Engineering have developed to advance marine science. EOI research is driven by a need for better observational data on issues of global importance, including the role of continental margin seeps in the global methane/carbon cycle, benthic ecology, and fisheries habitat; the role of hydrothermal systems in global biogeochemical cycles, including carbon dioxide removal; the potential impact of deep-sea mining of metal sulfides on ecosystem services provided by hydrothermal vents; and how hydrothermal iron functions as an essential nutrient. NOAA Ocean Exploration, the Schmidt Ocean Institute, the Ocean Exploration Trust, and the National Science Foundation have supported and collaborated in this work. Global exploration of the deep sea with the purpose of understanding global ocean processes remains a cornerstone of EOI science.

Methane gas plumes have been discovered to issue from the seafloor in the Puget Sound estuary. These gas emission sites are co‐located over traces of three major fault zones that fracture the entire forearc crust of the Cascadia Subduction Zone. Multibeam and single‐beam sonar data from cruises conducted in years 2011, 2018, 2019, 2020, and 2021 identified the acoustic signature of 349 individual bubble plumes. Dissolved CH4 gas from the plumes combines to elevate seawater methane concentrations of the entire Puget Sound estuary. Fluid samples from adjacent terrestrial hot springs and deep‐water wells surrounding the estuary contain a helium‐3 isotope signature, suggesting a deep fluid source located near the underlying Cascadia Subduction Zone plate interface. However, limited data from this pilot study suggest that Puget Sound seawater emission sites lack both similar chemical isotope signatures and elevated thermal anomalies that would be expected from association with a deep plate‐interface reservoir. A shallow reservoir within the Holocene sediments that cover the older Puget Sound basement with horizontal transfer to the thinly covered Alki Point and Kingston Arch anticlines is also a possibility, as has been suggested for other methane seep areas. The existence of vigorous marine methane plumes arising from areas of thin sediment cover associated with deeply penetrating forearc fault zones but presenting no thermal or chemical anomalies found in other similar forearc environments, remains an unresolved paradox. Plain Language Summary Puget Sound is a large inland sea located in western Washington State where seawater circulation is dominated by vigorous tidal forcing from the North Pacific Ocean. The deep Puget Sound is the largest estuary in North America measured by contained water volume and the second largest estuary after Chesapeake Bay in terms of area. Shipboard sonar images have revealed approximately 349 bubble plumes of methane gas and fluid rising from the seafloor of the estuary. Large clusters of bubble plume sites are concentrated over the major regional fault zones that penetrate the western North American plate beneath Puget Sound, including the South Whidbey Island Fault, the Seattle Fault, and the Tacoma Fault Zones. Although the forearc Puget Basin is surrounded by terrestrial hot springs and water wells that show a clear chemical isotope signature of fluid arising from the underlying Cascadia Subduction Zone plate interface, based on our limited sampling there is currently no evidence for similar chemical or temperature anomalies in the Puget Sound plumes and the source of the methane bubble plumes is still unidentified. Key Points Extensive methane bubble plumes have been discovered on the Puget Sound seafloor The emission sites of these plumes are associated with major fault zones that penetrate the Cascadia forearc Dissolved methane arising from the plumes is mixed throughout the estuary by tides and local mixing