Expedition Technology (United States)

Summary: Disaster response often requires complex, multi-agency efforts and brings together responders and leaders from various backgrounds. International response can be complicated by varying clinical practices, lack of coordination, and differing cultures and languages. Tabletop exercises are well-established techniques to improve readiness and coordination in disaster response. In April 2024, an international group of disaster medicine experts from the United States, Canada, and France designed, planned, and facilitated a multi-agency tabletop exercise for the disaster response elements based in Toulouse, France. A structured post-exercise debrief with this team was performed, and distinct themes were extrapolated, including successes, challenges, and lessons learned in designing, planning, and facilitating this tabletop. Successes in designing and planning the exercise included multidisciplinary collaboration, early coordination with the core planning team, detailed scenario design, the experience of planners, well-timed injects, and good stakeholder participation. Challenges include understanding the capabilities of responding agencies, language barriers, last-minute changes and participation, changing objectives, time zone coordination, and lack of follow up. Successes in facilitating the tabletop included clarity and design of the exercise, adequate logistics, an appropriate number of participants and facilitators, not deviating from the master scenario events list (MSEL), real-time translation, collaboration from various stakeholders, adaptability and flexibility of facilitators, and a well coordinated emergency operations center. Challenges in facilitating the tabletop included language barriers, facilitators’ lack of familiarity with the host country’s response system, perceived bias that affected communication, lack of communication method between facilitators, lack of pre-exercise introductions, and post exercise debrief role confusion. International multi-agency tabletop exercises pose unique challenges. The successful completion of these exercises is dependent on early and comprehensive planning, a thorough understanding of the stakeholder capabilities, clear and concrete objectives, adequate translation capabilities, good pre- and post-exercise follow up, and facilitator flexibility and adaptability.

<strong class="journal-contentHeaderColor">Abstract.</strong> Permafrost is degrading, raising concerns about its impact on global climate. Taliks, year-round unfrozen layers of ground in permafrost environments, affect Arctic hydrological and carbon dynamics and contribute to permafrost degradation. Despite their importance, they are seldom studied because of the difficulty in identifying them. Water tracks (zones overlying permafrost concentrating water flow) have an important role in controlling catchment hydrology, yet their contribution to talik formation remains poorly understood. The objective of this study is to detect and characterize suprapermafrost taliks in three-dimensions at high spatial resolution (dm-scale), with a specific focus on those located beneath water tracks. Fieldwork was conducted in a discontinuous permafrost area near Eight Mile Lake, Alaska (USA), during winter using a Ground-penetrating radar with a 600 MHz antenna. Ground-penetrating radar proved to be a reliable tool for imaging talik depth and extent. While talik tops were clearly detected with a root mean square error of 17 cm, their bottoms were less identifiable due to limited signal penetration. Both isolated and lateral suprapermafrost taliks were observed at the site. Importantly, taliks were more present, shallower and thicker in water tracks than in their adjacent areas. Additionally, thicker snow cover and topographic depressions were significantly associated with shallower taliks (respective significant correlations of -0.65 and 0.53). Water tracks thus appear to be hotspots for talik formation and expansion, with important implications for winter subsurface hydrological connectivity. These findings highlight the need for increased attention to the processes occurring during the winter in the water tracks environments.

The majority of our knowledge about plastic pollution is based on microplastics, defined as particles measuring between 500 µm and 5 mm. Due to technical limitations, our understanding of nanoplastics (smaller than 1 µm) remains limited. Nonetheless, it is widely accepted that nanoplastics are more abundant, more widely dispersed, and pose a potentially greater risk to ecosystems and human health than microplastics1. Nanoplastics also differ from microplastics in terms of transport mechanisms, reactivity with other particles, interaction with light, and bioavailability.Given these distinctions, since 2021, we have conducted several field campaigns to quantify nanoplastics in the Mediterranean Sea, using the research vessel Expedition 7th Continent. A rigorous methodology was developed, encompassing sampling, isolation, and quantification via Py-GC-MS/MS, to ensure highly reliable results2, 3. Particular attention was paid to quality control, which is a critical concern in nanoplastic analysis.We detected nanoplastic concentrations in the Mediterranean in the µg/L range. These high concentrations are notable and likely result from the fact that the semi-enclosed Mediterranean Sea serves as the ultimate sink for plastic pollution originating from coastal countries, where plastic waste degrades into nanoplastics. The presentation of these data will also address their impact on current ecological risk assessment thresholds for plastics in marine environments. References cited :Mitrano, D. M.; Wick, P.; Nowack, B., Placing nanoplastics in the context of global plastic pollution. Nat Nanotechnol 2021, 16, (5), 491-500. Albignac, M.; de Oliveira, T.; Landebrit, L.; Miquel, S.; Auguin, B.; Leroy, E.; Maria, E.; Mingotaud, A. F.; ter Halle, A., Tandem mass spectrometry enhances the performances of pyrolysis-gas chromatography-mass spectrometry for microplastic quantification. J. Anal. Appl. Pyrol. 2023, 172, 105993. Albignac, M.; Maria, E.; De Oliveira, T.; Roux, C.; Goudouneche, D.; Mingotaud, A. F.; Bordeau, G.; ter Halle, A., Assessment of nanoplastic extraction from natural samples for quantification purposes. Environmental Nanotechnology, Monitoring &amp; Management 2023, 20, 100862.

The prevalence of urinary incontinence (UI) in older women in low- and middle-income countries (LMICs) is not well understood. We conducted a rapid literature review to assess the burden of UI in this population and contextualize findings from a household survey of women aged 40 and older in Nouna, in northwestern Burkina Faso. The rapid review included 21 survey articles. UI prevalence for LMIC women 40 or older varied greatly (6%-80%), with differences by socio-demographics, gynecological factors (menopausal status, birth outcomes), comorbidities (age, education, obesity, diabetes, hypertension, arthritis), behaviors (smoking status) and survey location. The studies used validated tools-the International Consultation on Incontinence Urinary Incontinence Short Form (ICIQ UI-SF) was most common (n = 4, 19%)-and bespoke tools that have not yet been validated. In Nouna, 983 (64.5%) of 1,524 women, completed the ICIQ UI-SF. Overall UI prevalence, defined as reporting leakage at least 2-3 times a week, was 2.6% (95% CI 1.73%-3.85%), descriptively increased with age from 0.5% in 40-49 year-olds to 6.6% in those 70 and over. Of those with UI, 88.5% experienced leakage daily, and 50% reported moderate or greater interference with daily life, yet most (88.5%) had not spoken to a healthcare provider. Multivariable analysis revealed that UI was more common among women who were not currently married and decreased with higher education levels. Both the rapid review and survey highlight the burden of UI among older women in LMICs, particularly as they age beyond 60. Given UI's association with physical and mental health, it is crucial to raise awareness of its burden, improve healthcare access, and integrate routine screening into basic healthcare services. Additionally, training healthcare providers and developing culturally appropriate interventions will help address stigma and ensure effective management of UI in this vulnerable population.

The International Ocean Discovery Program (IODP) Expedition 386, Japan Trench Paleoseismology, represents the first utilization of giant piston coring (GPC) within scientific ocean research drilling. This allowed for a Mission Specific Platform (MSP) multi-site, multi-hole, shallow subsurface coring in an ultra-deep water subduction zone trench. The primary objective of the expedition was to investigate the concept of submarine paleoseismology in the Japan Trench, which involves studying long-term records of deposits in the deep sea that can provide insights into past earthquake events. In this paper, we compile and interpret initial shipboard data and results to (1) establish first-order event stratigraphic correlation of thick event beds (> 50 cm in thickness) between sites, (2) test previously published event-stratigraphic predictions of earthquake-related event deposits as proposed based on high-resolution hydro-acoustic subbottom profiler (SBP) data, and (3) derive SBP-scale event deposits age estimates to (4) discuss the advantages and limitations of giant piston coring for scientific drilling operations and the potential of new event stratigraphy results for advancing submarine paleoseismology.The findings of the study identified a total of 77 SBP-scale event beds across 15 sites along a trench-parallel transect spanning over 600 km. These event beds exhibit clear expressions in SBP data, with approximately 49 % matching precisely with SBP units previously identified by Kioka et al. (2019a). For the remaining 51 % of SBP-scale event beds, thin, acoustically-transparent bodies were observed between high-amplitude horizons, for which SBP-based seismic interpretation alone would not be definitive. Consequently, the study concluded that the SBP-scale event-stratigraphy observed in IODP 386 cores validates the event-bed mapping conducted by Kioka et al. (2019a) and improves SBP interpretation for event beds in the 0.5 to 1 m thickness range.The initial age constraints obtained from shipboard radiolarian biostratigraphy enable us to provide rough estimates of event ages by linearly interpolating between previously dated events occurring less than 2000 years ago and a datum around 11,000 years ago reported in four boreholes from trench basins in the Southern, Central, and Northern Japan Trench. Inter-site stratigraphic correlation reveals distinct SBP-scale event stratigraphies for the trench segments located to the north and south of the structurally complex “boundary area” at approximately 39.3–39.4°N, which is hypothesized to potentially act as a persistent rupture barrier for megathrust earthquakes. We observe more frequent but thinner event deposits in the Southern and Central Japan Trench, and fewer but thicker event beds in the Northern Japan Trench. This spatial variation may be related to the different seismogenic behavior of the various asperities along the Japan Trench megathrust and/or to differences in the response of slope sediments to earthquake shaking. However, here-presented investigations at the SBP-scale level are deemed too simplistic for robust application of the “submarine paleoseismology” approach. The extensive and high-quality dataset from IODP GPC, coupled with the encouraging initial correlation results presented here, leads us to hypothesize that further detailed studies can identify and characterize event deposition dynamics at the micro-facies level, refine sediment provenance, and constrain precise event ages necessary for evaluating synchronicity in paleoseismological interpretation. These studies will also enable robust exploration of along-strike correlations or variations, facilitating the extraction of paleo-earthquake signals from Japan Trench event stratigraphies.

Object detection in 3D point clouds is essential in fields such as geospatial intelligence and autonomous driving. The common machine learning problem of scarce labeled training data is even more acute with 3D point cloud data. Active learning provides a framework to prioritize the additional effort to manually annotate unlabeled training data. Most active learning methods for deep learning fall into one of two categories: uncertainty methods and diversity methods. Uncertainty methods select data by assessing model outputs for their confidence and consistency and are therefore dependent on the expected output of each deep learning task. These methods tend to select batches of informative yet highly similar samples to label. Diversity-based active learning aims to create a labeled dataset that is both varied and representative of the remaining unlabeled data. Diversity methods operate directly on the feature representations of the inputs and are thus more flexible with respect to the specifics of the deep learning task. Our current work explores applying diversity methods and uncertainty-diversity hybrid methods to 3D object detection. We evaluate various approaches to incorporate diversity, including K-Medoids clustering, core set selection, and furthest nearest neighbors. We address the high dimensionality of the features extracted from a VoxelNet-based object detector by varying the distance metric used in the active learning algorithms. Furthermore, we compare our results to those obtained using only uncertainty methods. We assess the performance and efficiency of each active learning method in addition to the representativeness and diversity of the labeled datasets produced. We find that hybrid uncertainty-diversity methods outperform other methods in terms of object detection AP50 throughout active learning, annotation efficiency, and class balance.

EXP’s IC3D system classifies SAR or LiDAR derived 3D point clouds using a deep representation learning approach, producing as output a vector of categorical posterior probabilities of target classifications. Such posterior probabilities are suitable observational inputs to a Bayesian belief network (BBN), such as the EXP Shadow Compass system. In concert with conditional probabilities of intermediate events depending on the observation states, the Bayesian network computes posterior probabilities for events conditionally dependent on those intermediate event states. We demonstrate this approach by computing posterior event probabilities for sample analyst scenarios with intermediate event conditional probabilities specified by analysts. Future work could include extending the Bayesian network approach to discovery of the network topology from analyst data.

Abstract Monitoring nuclear reactors is an important safety and security task with growing requirements. We explore the possibility of using seismic and acoustic data for inferring the power level of an operating reactor. Continuous data recorded at a single seismoacoustic station that is located about 50 m away from a research reactor was visualized and analyzed. The data show a clear correlation between seismoacoustic features and reactor main operational states. We designed a workflow that includes two machine learning (ML) models to classify the reactor operational states (OFF, transition, and ON) and estimate reactor power levels (10%, 30%, 50%, 70%, and 90%). We applied and compared five ML algorithms for the reactor OFF-transition-ON and four approaches for the power level classification. We also compared the performance of ML models trained with seismic-only, acoustic-only, and both types of data. Five-fold cross validations were implemented to assure a thorough evaluation of the model performances. The results show the extreme boosting gradient algorithm worked best for the first model, whereas random forests performed best for the second model. Combining seismic and acoustic data leads to better performance than using a single type of data. Seismic data contributed more than acoustic data for both models. We reached an accuracy of 0.98 for reactor OFF and ON. The accuracies for the transition state and power levels are less optimal with a minimum accuracy of 0.66. However, our results suggest seismic and acoustic data contain useful information about the transition state as well as power levels. Seismic and acoustic data could be integrated with other observations to improve monitoring performance.

Les récipients à eau façonnés en algue sont des biens emblématiques de la culture matérielle aborigène de lutruwita (Tasmanie). C’est la quête du plus ancien spécimen connu, collecté lors de l’expédition de Bruni d’Entrecasteaux (1791-1794), que retrace cet article. Depuis longtemps, cet objet inestimable, entré au musée de Marine du Louvre par le biais de la collection Denon, semblait avoir disparu. Il se cachait, anonyme, parmi les biens orphelins des collections du musée du quai Branly - Jacques Chirac.

Liquid lead-bismuth eutectic (LBE) is an important candidate to become the primary coolant of future, generation IV, nuclear fast reactors and Accelerator Driven System (ADS) concepts. One of the main challenges with the use of LBE as a coolant is to avoid its oxidation which results in solid lead oxide (PbO) precipitation. The chemical equilibria governing PbO formation are well understood. However, insufficient kinetic information is currently available for the development of LBE-based nuclear technology. Here, we report the results of experiments in which the nucleation, growth and dissolution of PbO in LBE during temperature cycling are measured by monitoring dissolved oxygen using potentiometric oxygen sensors. The metastable region, above which PbO nucleation can occur, has been determined under conditions relevant for the operation of LBE cooled nuclear systems and was found to be independent of setup geometry and thus thought to be widely applicable. A kinetic model to describe formation and dissolution of PbO particles in LBE is proposed, based on Classical Nucleation Theory (CNT) combined with mass transfer limited growth and dissolution. This model can accurately predict the experimentally observed changes in oxygen concentration due to nucleation, growth and dissolution of PbO, using the effective interfacial energy of a PbO nucleus in LBE as a fitting parameter. The results are invaluable to evaluate the consequences of oxygen ingress in LBE cooled nuclear systems under normal operating and accidental conditions and form the basis for the development of cold trap technology to avoid PbO formation in the primary reactor circuit.