Site Of Deposition Research Articles

Simulation of Dendrite Growth with a Diffusion-Limited Aggregation Model Validated by MRI of a Lithium Symmetric Cell during Charging

Lithium metal batteries offer high energy density but are challenged by dendrite growth, which can lead to short circuits and battery failure. Multiple models with varying degrees of accuracy and computational cost have been developed to understand and predict dendrite growth. This study presents a simple model to simulate macroscale dendrite growth on lithium metal electrodes. The model uses a 3D single-particle Diffusion-Limited Aggregation (DLA) algorithm with an electric field bias to simulate dendrite growth. The electric field bias was introduced into the model with an important parameter, namely the biasing factor c, which determines the balance between diffusion and electric field effects. Before performing the simulation with the proposed model, the dendrite growth in a lithium symmetric cell during charging was measured by sequential 3D magnetic resonance imaging (MRI). These data were then used to validate the simulation, as the dendrite structure in each measured MRI time frame was used a starting point for a new simulation, the results of which were then validated with the measured dendrite structure of the next time frame. The best agreement between the simulated and measured dendrite structures using the overlap and displacement of deposition sites metrics was obtained at the biasing factor c = 0.7. This agreement was also good in terms with the fractal dimension of the dendrite structures. The proposed method offers a simple, accurate, and scalable framework for predicting dendrite growth over long deposition periods, making it a valuable tool for studying dendrite suppression under real-world battery charging conditions.

Particulate matter-induced epigenetic modifications and lung complications.

Air pollution is one of the leading causes of early deaths worldwide, with particulate matter (PM) as an emerging factor contributing to this trend. PM is classified based on its physical size, which ranges from PM10 (diameter ≤10 μm) to PM2.5 (≤2.5 μm) and PM0.5 (≤0.5 μm). Smaller-sized PM can move freely through the air and readily infiltrate deep into the lungs, intensifying existing health issues and exacerbating complications. Lung complications are the most common issues arising from PM exposure due to the primary site of deposition in the respiratory system. Conditions such as asthma, COPD, idiopathic pulmonary fibrosis, lung cancer and various lung infections are all susceptible to worsening due to PM exposure. PM can epigenetically modify specific target sites, further complicating its impact on these conditions. Understanding these epigenetic mechanisms holds promise for addressing these complications in cases of PM exposure. This involves studying the effect of PM on different gene expressions and regulation through epigenetic modifications, including DNA methylation, histone modifications and microRNAs. Targeting and manipulating these epigenetic modifications and their mechanisms could be promising strategies for future treatments of lung complications. This review mainly focuses on different epigenetic modifications due to PM2.5 exposure in the various lung complications mentioned above.

Divergent seed dispersal outcomes: Interactions between seed, disperser, and forest traits.

Animals disperse seeds in various ways that affect seed deposition sites and seed survival, ultimately shaping plant species distribution, community composition, and ecosystem structure. Some animal species can disperse seeds through multiple pathways (e.g., defecation, regurgitation, epizoochory), each likely producing distinct seed dispersal outcomes. We studied how seed traits (size and toughness) interact with disperser species to influence seed dispersal pathway and how this ultimately shapes the proportion of seeds deposited in various habitat types. We focused on three frugivorous species of duikers (African forest antelopes) in the Dja Faunal Reserve, a tropical rainforest in southern Cameroon. Duikers can both defecate and regurgitate seeds, the latter predominantly occurring during rumination at their bedding sites (or "nests"). We located duiker nests and dungs along 18 linear 1-km-transects to assess: (1) how seed traits affect the likelihood of dispersal via defecation versus regurgitation, (2) if defecated versus regurgitated seeds are deposited at different rates in different forest types (assessed by indigenous Baka), microhabitats, and forest structural attributes (measured by drone lidar), and (3) if these differ between three duiker species that vary in size and diel activity patterns. We found that duikers predominantly defecated small seeds (<3 mm length) and regurgitated larger and tougher seeds (>10 mm length), the latter including 25 different plant species. The three duiker species varied in their nesting habits, with nocturnal bay duikers (Cephalophus dorsalis) nesting in dense understory vegetation at proportions 3-4 times higher than Peter's and yellow-backed duikers (Cephalophus callipygus and Cephalophus silvicultor). As a result, bay duikers deposited larger regurgitated seeds at a higher rate in habitats with denser understory where lianas and palms predominate and near fallen trees. This directed regurgitation seed deposition likely plays an important and unique role in forest succession and structure. This study highlights the importance of ungulate seed dispersal by regurgitation, a vastly understudied process that could impact many ecosystems given the prevalence of ruminating ungulates worldwide.

Assessment of Optical and Scanning Electron Microscopies for the Identification and Quantification of Asbestos Fibers and Typical Asbestos Bodies in Human Colorectal Cancer Tissues

Asbestos research, identification, and quantification have been performed over the years, and the relationship between fiber inhalation and lung disease development is well defined. The same cannot be said for the gastroenteric system: the International Agency for Research on Cancer (IARC) believes that colorectal cancer (CRC) could be associated with asbestos exposure, but research has not demonstrated a casual nexus between exposure and CRC, despite highlighting an association tendency. The combination of scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) is the most applied technique in asbestos fiber identification in tissues and intestinal mucosa. In this study, SEM/EDS was applied to evaluate the presence of asbestos fibers and bodies (ABs) inside the tissue of eleven patients affected by CRC who had undergone environmental exposure due to living in an asbestos-polluted area where an Eternit plant had been active in the past. This technique was coupled with optical microscopy (OM) to verify whether the latter could be applied to evaluate the presence of these mineral phases, with the goal of understanding its suitability for identifying fibers and ABs in colon tissues. In addition to verifying the presence of fibers, this study allowed us to identify the deposition site of said fibers within the sample and possibly detect associated tissue reactions using OM, over a shorter time and at lower costs. Despite being a preliminary and descriptive work, the obtained results allowed us to propose a method involving first-sample OM observation to identify regulated (fibers with a length ≥ 5 μm, a thickness ≤ 3 μm, and a length/thickness ratio &gt; 3) asbestos phases and ABs in the extra-respiratory system. In fact, OM and SEM/EDS provided similar information: no asbestiform morphology or ABs were found, but phyllosilicates and other inorganic materials were identified. This research needs to be continued using higher-resolution techniques to definitively rule out the presence of these fibers inside tissues whilst also increasing the number of patients involved.

Zinc Affinity and Hydrogen Evolution Trade‐Off for Homogenous Zn Deposition in Reversible Zn Ion Batteries

AbstractZn ion batteries (ZIBs) are promising for large‐scale energy storage but their practical application is plagued by inhomogeneous Zn deposition. Despite much effort, the harm of simultaneous hydrogen evolution reaction (HER) during plating to Zn deposition, has not received sufficient studies. Herein, Sn‐modified Cu nanowires (Sn@CuNWs) with Sn‐Cu core–shell nanostructure to achieve uniform Zn deposition by zinc affinity‐HER tendency trade‐off are fabricated. Confirmed by both theoretical calculation and practical characterization, the nanowires with high zinc affinity and large deposition sites facilitate Zn deposition, while the enlarged HER tendency harmful to Zn plating is inhibited by Sn nanoshell. Therefore, the Zn deposited Sn@CuNWs anode delivers a long lifespan of 800 h at 5 mA cm−2, and the full cell exhibits a high capacity of 294.4 mAh g−1 at 5 A g−1 and a high capacity retention of 97.8% after 2500 cycles. This work reveals the importance of HER regulation for reversible Zn deposition, which should be noticed in further research.

Modelling chronologically ordered radiocarbon dates in R

Abstract Studies with multiple radiocarbon dates often contain useful information on the relative locations of the dated levels. Such information can be used to obtain robust, integrated site chronologies, with at times more precise ages than those of the individual dates, where outliers can be identified and downweighted, and where the ages of any undated levels can also be estimated. Examples include trees with radiocarbon dates separated by exactly known amounts of yearly tree-rings, or sedimentary sites where ages further down the stratigraphy can be assumed to be older than ages further up. Here we present coffee, an R package for Bayesian models that apply chronological ordering for fossils and environmental events. Coffee runs natively within the popular and versatile R environment, with no need for importing or exporting data or code from other programs, and works with plain-text input files that are relatively easy to read and write. It thus provides a new, transparent and adaptable educational and research platform designed to make chronology building more accessible.

Santos Basin as an Example of a Shear-Driven Core Complex in a Transform Marginal Plateau

It is proposed a new model on the kinematics of strain partitioning for the breakup of the Santos and Namibe conjugate basins. The model is based on observed strike-slip corridors and low-angle detachments with metamorphic core complexes, which accommodated the deformation in a mega relay zone. Through detailed reconstructions of this segment of the South Atlantic, collecting multidisciplinary data from previous researchers, and considering the relative relationship between Africa and South America during the breakup process, it is herein reexamined key evidence of how the Brazilian side became so wide, and acted as an accommodation zone during the Aptian. The 600 km Long transpressional-dextral Proterozoic Ribeira Belt is the cradle of the transtensional-sinistral Santos-Namibe strike-slip rift propagator. These conjugate basins evolved as a large-scale relay zone, developing an oblique-left-lateral extensional corridor during the Aptian, balancing mechanically coeval deformations from two sub-parallel spreading branches, traveling from North and South, but hundreds of kilometers apart from each other. Proterozoic inheritance, and the dynamic clockwise rotation of South America (far-field stresses) controlled strain partitioning between the Campos/Benguela basins and the Pelotas/Walvis basins. The onset of seafloor spreading around the Falkland (Malvinas) Island, triggered the relative clockwise rotation of the southernmost tip of the South America plate, and the intrusion of transversal dike swarms of the Ponta Grossa Arch, which is interpreted as fissural magmatism, comparable to a regional opening mode(type I) fracture system. Plate kinematic transport direction inferred from plate reconstructions is mainly EW. The step-over oblique-slip of this relay zone widened the Santos Basin in the NW-SE direction, often mistakenly misinterpreted as the extension direction in the Santos Basin. This NW path is the direction of the maximum elongation within an E-W shear corridor. Our work details a new and unprecedented strike-slip structural framework of the Santos Basin, with large-scale basement-involved folding around the Outer High, which evolved to an obliquely sheared active low-angle detachment system, simultaneously influenced by the thermal anomaly of the Tristan-Gough plume, responsible for magmatic thermal weakening and thermal-induced uplift. Magmatic underplating may have facilitated the doming process. The Santos Basin is located at the heart of a Transform Marginal Plateau, as previously proposed. It is composed of a magmatic crust, with fragmented slices of continental crust, obliquely sheared during successive transform movements, with possible magmatic underplating. This kinematically linked system of normal faults, strike-slip faults, flexural folds, and detachment faults has direct impact on understanding the properties of world-class oil and gas reservoirs in the Brazilian Pre-Salt Supergiant Province. With the ongoing regional transgression, the active structural highs were the site of deposition of the carbonate reservoirs that host an in-place volume around a hundred billion barrels of hydrocarbons, considering the whole province.

Spatially Confined Alloying of Pt Accelerates Mass Transport for Fuel Cell Oxygen Reduction.

Pt-based alloy with high mass activity and durability is highly desired for proton exchange membrane fuel cells, yet a great challenge remains due to the high mass transport resistance near catalysts with lowering Pt loading. Herein, an extensible approach employing atomic layer deposition to accurately introduce a gas-phase metal precursor into platinum nanoparticles (NPs) pre-filled mesoporous channels is reported, achieved by controlling both the deposition site and quantity. Following the spatially confined alloying treatment, the prepared PtSn alloy catalyst within mesopores demonstrates a small size and homogeneous distribution (2.10 ± 0.53nm). The membrane electrode assembly with mesoporous carbon-supported PtSn alloy catalyst achieves a high initial mass activity of 0.85 A at 0.9V, which is attributed to the smallest local oxygen transport resistance (3.68 S m-1) ever reported. The mass activity of the catalyst only decreases by 11% after 30000 cycles of accelerated durability test, representing superior full-cell durability among the reported Pt-based alloy catalysts. The enhanced activity and durability are attributed to the decreased adsorption energy of oxygen intermediates on Pt surface and the strong electronic interaction between Pt and Sn inhibiting Pt dissolution.

The influence of topography on subaqueous gravity flows: a case study from the Jurassic Los Molles Formation, Neuquén Basin, Argentina

ABSTRACT Subaqueous sediment gravity flows experience modifications when they interact with slope and basin-floor topography, impacting facies, geometries, and architectural patterns of the deposits. Understanding these processes is critical for reservoir-quality and trap predictions in deep-water stratigraphic plays. A comprehensive literature summary of the topographic influence on subaqueous gravity flows and an interpretation applied to the basin-floor turbidite system of the late synrift Los Molles Formation in the Neuquén Basin of Argentina are provided. In the study area, a high-resolution satellite image, drone imagery, and 30 logs (about 5000 m total thickness) were measured, focusing on facies analysis, paleocurrents, bed thicknesses, and large-scale thickness variations. Studies describing topographic confinement of sediment gravity flows have used five approaches: 1) Paleocurrent analysis: paleocurrents following structural trends and variations within the same bed (flow deflection and reflection). 2) Facies analysis: complex facies variations on short distances and increased number of hybrid beds and debrites near barriers (flow transformation), loading, convoluted structures, and bidirectional ripples (flow reflection), and sand–mud couplets or thick mudcaps (flow ponding). 3) Small-scale (decimeter to meter) thickness variations: beds thickening towards topography, beds thinning on top of topography (onlaps), and low thinning rates (loss of flow competence, flow containment). 4) Architectural analysis: aggradational stacking, lateral stacking away from topographic barriers, and fill–spill successions. 5) Large-scale thickness (tens of meters) variations: increased fan system thickness across topographic lows. An extended version of an existing classification scheme on degree of confinement is proposed: C0 (unconfined): no flow modification evidence present, and compensational stacking is a classic architectural pattern. C1 (weakly confined): variations in regional paleocurrent directions, minor thickness variations against small-relief barriers, large (basin scale) thickness variations. C2a (confined) to C2b (highly confined): onlaps against high-relief barriers, paleocurrent direction variations on the same bed, bed thickening against topography, facies evidencing flow reflection, increased number of hybrid beds, aggradational stacking, and high percentage of beds continuous over 500 m distances (tabular beds). C2a and C2b are considered end members of a spectrum where the amount of evidence listed can vary. C3 (ponded): sand mud couplets or thick mudcaps. Higher confinement categories might have indicators from the weaker confinement categories. The lower fan in the Los Molles Fm. turbidite system is classified as weakly confined. A complex sediment routing followed structural trends inherited from the rift phase of the basin. The basin-floor had irregular water depths that led to preferred sites of deposition. Hybrid beds are mostly found at the fringes of the lower part of the succession and might be associated with an above-grade slope profile on a footwall scarp. Lastly, the Los Molles Fm. basin-floor beds present high thinning rates (average 1.5 m/km) and the system stacks compensationally, pointing to null interaction against basin margins.

Reconstructing the Zama (Mexico) discovery source to sink story, Part I; detrital zircon U–Pb and (U‐Th)/He provenance analysis and implications for sediment source terranes

AbstractThe Zama discovery was identified off the coast of Tabasco, Mexico, in the Sureste Basin of the Gulf of Mexico and is hosted in a three‐way closure in the Upper Miocene. This study conducted a detailed detrital zircon (DZ) U–Pb and (U‐Th)/He provenance analyses on samples from sandstone reservoirs in the Zama‐3 and Zama‐2ST1 wells. A total of 22 sandstone samples (11 from each well) were collected for DZ U–Pb and (U‐Th)/He dating from different reservoir zones, testing the hypothesis that different zones were whether originally derived from varied sedimentary source terranes and associated transport pathways to the Zama mini‐basin depositional site. Additional objectives include determination of maximum depositional ages, reconstruction of paleofluvial systems, and exploring the temporal evolution of the drainage region and hinterland tectonics. The DZ U–Pb age spectra from both Zama wells have remarkably homogenous DZ signatures with very similar DZ age modes and modal percentages, displaying dominant Permian/Chiapas Batholith (ca. 35%–45%), Mesoproterozoic/Oaxaquian (ca. 20%–35%), Early Palaeozoic/Acatlán (ca. 8%–20%), and Cenozoic magmatic arc (ca. 15%–25%) age modes, as well as some subsidiary (&lt;5%) early Proterozoic/Archean and Early Cretaceous DZ age components, linked to recycled lower Palaeozoic strata and the Guerrero Terrane and Alisitos arc, respectively. Despite differences in paleocurrent directions, deduced from image logs, there are no systematic differences in DZ spectra, indicating a consistent sediment provenance and no changes in source area. All Zama samples analysed in the study are characterized by abundant syn‐depositional Late Miocene DZ grains, clustering between 8.6 and 10.2 Ma, corroborating a Tortonian (Late Miocene) depositional age, and yield rapid sediment accumulation rates of ca. 200 m in &lt;1.4 Ma (13 m/Myr). Doubled zircon U–Pb and (U‐Th)/He age pairs are indicative of recycling of early Mesozoic rift strata and Paleogene and younger Chiapas basement. These new DZ U–Pb and (U‐Th)/He data have a nearly invariant Tortonian sediment provenance that is similar to the modern Grijalva River flowing generally northward out of the Chiapas highlands. The paleo‐Grijalva drainage, providing sediment to the Late Miocene Zama mini‐basin, was likely drastically larger than the present catchment as it involved 10 Ma plutonic sources that were subsequently downfaulted along the Pacific coast in the latest Miocene. Importantly, DZ U–Pb age components are consistent with Oaxaquia, early Acatlán, and Guerrero/Alisitos signatures and point to sourcing from the Chortis block during its tectonic eastward translation. Such a scenario would allow for a substantially larger Miocene paleo‐drainage that would have encompassed both Chiapas and portions of Chortis. The Miocene tectonic translation of Chortis and erosion of a large and tectonically active hinterland would also reconcile the dramatically larger Middle to Late Miocene sediment supply, funnelling a large influx of sediment into the southern Gulf of Mexico. Rapid Late Miocene sediment accumulation in the salt‐defined Zama mini‐basin must have involved sustained sediment flux via the paleo‐Grijalva drainage and was likely facilitated and focused by continued salt deflation due to sediment loading, as described in Part II. Thus, our work provides new scientific insights into one of the largest hydrocarbon discoveries in Mexico in recent years.

Detrital zircon in Pleistocene aeolianite of the Isipingo Formation at Cape Vidal, KwaZulu-Natal, South Africa, gives age and Hf isotope signatures without provenance significance

Abstract Pleistocene (50 to 70 ka) aeolianite of the Isipingo Formation (Maputaland Group) at Cape Vidal, northern KwaZulu-Natal province, South Africa, contains a combination of three detrital zircon age fractions (A: 940 to 1150 Ma, B: 470 to 720 Ma, C: 230 to 280 Ma) that are also known from Holocene sediments in eastern South Africa, Mesozoic – Cenozoic sandstones in southern Mozambique and from the Carboniferous to Jurassic Karoo Supergroup. Archaean and Palaeoproterozoic bedrock of the Kaapvaal Craton, which is exposed in the drainage basins of rivers that have provided detritus to coastal sedimentary basins, is represented by one single Archaean zircon. Combined laser Raman micro-spectroscopy and estimates of accumulated alpha radiation dose from U and Th concentrations indicate that the virtual absence of zircon older than late Mesoproterozoic cannot be attributed to selective removal of radiation-damaged zircon grains by abrasion during erosion and transport. The Isipingo Formation sandstone at Cape Vidal is a product of sedimentary recycling, potentially involving river transport from the continental hinterland, water- and wind-borne drift parallel to the coast and local recycling. Because of the similarity in detrital zircon distribution patterns of the sandstone and all of its potential Palaeozoic to Cretaceous sedimentary precursors, detrital zircon data cannot provide useful information on the relative importance of these processes, or on the routing of detritus to its final site of deposition.

Ultralong Bistable, Electrolytic MnO2-Based, Electrochromic Battery Enabled by Porous, Low-Barrier, Hydroxylated TiO2 Interface.

Electrochromic (EC)battery technology shows great potential in future "zero-energy building" by controlling outdoor solar transmission to tune heat gain as well as storing the consumed energy to reuse across other building systems. However, challenges still exist in exploring an electrochemical system to satisfy requirements on both ultra-long optical memory (also called bistability) without continuous power supply and high energy density. Herein, an ECbattery is proposed to demonstrate ultra-long bistability (>760h) based on the reversible deposition and dissolution of manganese oxide (MnO2) without the addition of any mediators. A porous low-barrier hydroxylated titanium dioxide (TiO2) interface is incorporated to synergistically enrich Mn2+-affinity active sites for deposition and effectively reduce the electron transport barrier of MnO2 for dissolution, thereby significantly improving the reversibility, high optical modulation (60.2% at 400nm), and energy density (352mAhm-2). The modification strategy is also verified on the cathode-less button cells with a much higher average coulombic efficiency (99.9%) compared to the batteries without the porous hydroxylated TiO2 interface (74.6%). These achievements lay a foundation for advancements in both electrochromism and Zn-Mn aqueous batteries.

Different bacterial communities of the coral area and its surrounding sediments in Daya Bay, South China Sea

Sediment in coral reef habitats has a tight interaction with coral reefs. Bacterial communities are a critical part of sediments and play a vital role in marine ecosystems, as well as coral reef habitats. To determine whether the bacterial structure of sediments differs between the inside and surrounding coral area, we compared the bacterial community on the surface of the dead coral skeleton (CS) and three soft sediment sites (SS, SS10, SS50) in and around the coral reef distribution of Dalajia Island in Daya Bay. Our results showed that bacterial diversity and composition of the coral skeleton had a significant difference with that of surrounding soft sediments. Proteobacteria and Actinobacteria were dominant in CS, and Proteobacteria and Bacteroidetes were dominant in SS, SS10, and SS50. Substrate type and environmental parameters are the main factors in the separation between coral skeletons and sediment. Salinity and pH were largely negatively correlated with CS, indicating they are primary factors that potentially impact coral mortality and revival. Heavy metals were positively related to sediments and they are potential threats to coral growth. Our work provides updated data on bacterial structure in the coastal coral area, contributing to policy-making and management of coastal activities to minimize the degradation of coral reefs.

Impact of diatomit on the transport behavior of unmodified and carboxyl-modified nanoplastics in saturated porous media

Due to the extensive use of plastic products and unreasonable disposal, nanoplastics contamination has become one of the important environmental problems that mankind must face. The composition and structure of porous media can determine the complexity and diversity of the transport behavior of nanoplastics. In this study, the influence of diatomite (DIA) on the nanoplastics transport in porous media is investigated by column experiments combined with XDLVO interaction energy and transport model. Results suggest that the recovery rates of unmodified polystyrene nanoparticles (PSNPs) and carboxyl-modified polystyrene nanoparticles (PSNPs-COOH) in the porous media containing DIA decreases compared with that in the pure quartz sand (QS), and the BTCs showed a “blocking” pattern. The presence of DIA inhibits the transport of both PSNPs and PSNPs-COOH, but the inhibition is not significant. This may be because the presence of DIA provides more favorable deposition sites for PSNPs and PSNPs-COOH to some extent. However, since DIA itself carries a certain negative charge, this can only play a role in compressing the double electric layer for PSNPs and PSNPs-COOH with the same negative charge, and cannot destabilize them. The migration capacity of PSNPs and PSNPs-COOH is strongest in the DIA-QS porous media at pH = 7, and is weak at pH = 9 and pH = 5. The inhibition of migration at pH = 9 can be attributed to the dissolution of the DIA surface under alkaline conditions and the formation of pore and defect structures, which provide more deposition sites for PSNPs and PSNPs-COOH. The presence of humic acid (HA) leads to an increase in the mobility of PSNPs and PSNPs-COOH, and the mobility is enhanced with HA concentration. The mobility of PSNPs and PSNPs-COOH in DIA-QS decreases with ionic valence and ionic strength, and PSNPs-COOH is more significantly inhibited compared to PSNPs.

Chronic contamination in the southern Gulf of Mexico coastal zone, as evidenced by meiofauna biological traits

Meiofauna is a good pollution indicator that reflects the ecological status of sediments and their linkages with overlying communities. However, long-term monitoring of this fauna is a developing research activity in most marine ecosystems. This study assessed seasonal spatial and temporal changes in meiofauna composition, abundance, and biological traits in the southern Gulf of Mexico sublittoral zone. We examined two questions: How do the meiofauna attributes vary spatially and seasonally? Which contaminants correlate with the distribution of meiofauna biological traits? We analysed sediment characteristics, metals, hydrocarbons, and meiofauna data collected at shallow coastal sites (<10 m) during eight annual surveys (2005–2020). Organic contamination increased when natural disturbances occurred, mainly in the dry season, decreasing the number of nematode taxa and increasing their abundance. During the eight yearly sampling events, nematodes, harpacticoid copepods, and polychaetes varied according to the sedimentary gradient. Chronic contamination (aromatic compounds, Cr, V, Cd, Cr) covaried with meiofauna biological traits. Our results point out meiofauna taxa (e.g., Anoplostoma, Halalaimus, Monhystera, harpacticoid copepods, saccocirrid polychaetes) as bioindicators of resilient and disturbed sites for terrigenous and transitional sediments, while in carbonate sediments dominated sensitive species. Resilient sites were exposed to the Grijalva-Usumacinta river discharges and the oil industry. Tolerant and opportunistic taxa such as the nematodes Anoplostoma and Xyala were classified as colonisers and non-selective deposit feeders. Conversely, sensitive taxa such as Halalaimus and harpacticoid copepods were semelparous, carnivorous, and persisters.

(Invited) Engineering Nanocomposite Substrates for Metal Deposition

Reversible metal plating is at the heart of aqueous based energy storage. Since virtually all metal anodes, e.g., Fe, and Zn, operate outside the stability window of water, it is thus essential to minimize their surface area by controlling the nucleation and growth during deposition and the pit formation during stripping.While epitaxial growth has shown promise as exemplified by the horizontal zinc deposition on graphene, an approximate heteroepitaxy, we will focus our effort in developing a nanocomposite substrate that promotes uniform nucleation sites and fast surface transport. The strategy is potentially highly scalable to address the need for large scale storage. Recently, we have shown that a nanocomposite substrate can induce single crystalline Li growth. By reacting FeF3 with Li, a nanocomposite of Fe and LiF is formed which features Fe nanoparticles of < 2 nm in size uniformly distributed in a matrix of LiF. Despite the global lithiophobility of the substrate, nano Fe domains provide energetically uniform nucleation sites for Li deposition while LiF enables rapid surface transport. Corporative merging of neighboring seeds lead to the formation of single crystalline Li. Unlike single crystal substrates, the nanocomposite features uniformly distributed, energetically equivalent sites for nucleation.We have adopted a similar strategy for Fe and Zn deposition. Preliminary results show that significantly improved macroscopic uniformity is achieved with the nanocomposite substrate. We will discuss materials requirements for operation in an aqueous environment and the general applicability of the approach for other materials.

Empirical approaches for non-linear site response: results for the ESG6-blind test

As a contribution to step 3 of the ESG6 blind prediction exercise, we present an application of two different, purely empirical approaches to estimate the strong ground motion at a soft site ("KUMA") from the observed ground motion at a reference rock site ("SEVO") for the two largest shocks of the Kumamoto 2016 sequence. The two methods estimate the non-linear transfer function between a reference rock and a sedimentary site by modifying the linear transfer function derived from weak motion recordings. The modification is based either on a machine learning tool based on a wide collection of Japanese weak and strong motion recordings and the associated site metadata (method 1), or on an estimate of a site-specific parameter related to an average non-linear site response (method 2). The acceleration time series are then derived at the sedimentary site of interest using an estimation of the time delay between wave arrivals at the rock and site stations, and a minimum phase assumption for the site transfer function. These predictions were made blindly, but after the ESG6 conference they could be compared both with the actual ground motion recorded at KUMA during the two shocks, and the average and range of all other predictions preformed for this benchmark. Both of these purely empirical methods provide an honorable prediction of usual engineering ground motion parameters of the two target events. The performance of these two purely empirical approaches is at least comparable to those of the numerical simulation methods for the foreshock—if not better—and slightly worse for the (largest) mainshock. As the methods required only recordings of weak motions at the target and a referent sites and very simple description of the soil profile. The use of moderate motions to constrain the frequency shift prediction for the second method and the consideration of an alternative phase modification are possible ways to improvement.Graphical

Ichnological analysis of glacially-influenced sediments from the late Pleistocene to Holocene on the southeastern Canadian margin: Implications for palaeoclimate and palaeoceanography

The study of trace fossils in glacially-influenced margins provides valuable insights into the changes in palaeoclimate and palaeoceanography during glacial-interglacial periods, by providing biological and ecological data of the benthic environment. Here we present a comprehensive ichnofabric characterisation of a sediment core located on an inter-canyon ridge on the SW Grand Banks Slope off Newfoundland, covering the Late Pleistocene–Holocene period (0–∼23 ka). The core analysis reveals 12 ichnogenera and an escape structure, with Phymatoderma, Tasselia, and Zoophycos being prominent and relatively abundant at specific levels. By examining the distribution of bioturbation content and degree along the core, we establish a strong association between moderate to high bioturbation and cold periods. The Last Glacial Maximum exhibits the highest abundance and diversity of trace fossils, particularly the deposit-feeding Phymatoderma and the deposit-feeding/equilibrium trace Tasselia, indicating benthic adaptation to seasonal food input and relatively high sedimentation rates. Conversely, the warmer deglaciation period shows limited bioturbation. Salinity stress may account for the abrupt decline in bioturbation degree during the early deglaciation. Additionally, the occurrence of large-sized Zoophycos coincides with the Younger Dryas cold event during the last deglaciation. These findings highlight the complexity of palaeoceanographic conditions and benthic environments in proximal glacially-influenced sites compared to distal hemipelagic and pelagic sites. The interplay between down-slope processes (such as turbidity currents and hyperpycnal flows) and along-slope processes (like contour currents) plays a crucial role in shaping the unique sedimentological regime of depositional sites and subsequently affecting the ichnofauna in glacially-influenced margins.

Interfacial interactions of nanoscale zero-valent iron particles with clay minerals in the aquatic environments: Experimental and theoretical calculation study

The environmental transport and fate of nanoscale zero-valent iron particles (nZVI) in soil and groundwater can be altered by their hetero-aggregation with clay mineral particles (CMP). This study examines the interactions between bare or carboxymethyl cellulose (CMC)-coated nZVI with typical CMP, specifically kaolinite and montmorillonite. Methods include co-settling experiments, aggregation kinetic studies, electron microscopy, Derjaguin–Landau–Verwey–Overbeek (DLVO) and extended DLVO (EDLVO) energy analysis, and density functional theory calculations, focusing on the pH dependency of these interactions. The EDLVO theory effectively described the interactions between nZVI and CMP in aquatic environments. Under acidic conditions (pH 3.5), the interfacial interaction between bare nZVI and kaolinite is regulated by van der Waals forces, while complexation, van der Waals forces, and electrostatic attraction govern the interaction of bare nZVI with montmorillonite, primarily depositing on the SiO face. In contrast, the positively charged AlO face and edge of CMP are the main deposition sites for CMC-coated nZVI through hydrogen bonding, van der Waals forces, and electrostatic attraction. At neutral (pH 6.5) and alkaline (pH 9.5) conditions, both bare and CMC-coated nZVI predominantly attach to the AlO face and edge, facilitated by complexation or hydrogen bonding, alongside van der Waals forces. The attachment of CMC-coated nZVI to CMP surfaces shows reversible aggregation or deposition due to the steric repulsion from the CMC coating. These findings hold significant implications for the environmental applications and risk of nZVI.

Histological characterization of downy mildew infection in wild rocket (Diplotaxis tenuifolia)

AbstractWild rocket downy mildew (DM), caused by oomycete Hyaloperonospora sp., is a widely spread disease reducing crop production and quality. New productive wild rocket varieties resistant to DM are crucial to control disease and ensure high quality leaves. A histological characterization of Hyaloperonospora sp. infection was performed in 11 wild rocket (Diplotaxis tenuifolia) accessions with contrasting DM responses (R, resistant; PR, partially resistant; S, susceptible). Samples of infected cotyledons, first and second leaves of 14‐day‐old seedlings were collected at 3, 6, 9, 21 and 24 h post‐inoculation (hpi) and 7 days post‐inoculation (dpi) and stained for appressoria and haustoria observation and tissue necrosis evaluation. Occurrence of appressoria on host surfaces was higher in leaves compared with cotyledons but unrelated with DM resistance response. Haustoria growth in mycelium was delayed in R accessions from 3 hpi, and signs of cell hypersensitivity reaction were observed at 9 hpi. At 24 hpi, necrotic spots limited pathogen growth in resistant accessions, whilst mycelium invaded larger mesophyll areas and produced more haustoria in susceptible ones. At 7 dpi, sporulation was heavy in S, restricted to droplet deposition sites in PR, and did not occur in R hosts. A rapid response of R accessions resulted in slower mycelium growth and longer infection periods. These traits have important agronomic value and should be considered in germplasm selection for breeding programmes aimed at crop protection. A better understanding of the host response to DM infection will allow selection of more suitable wild rocket accessions in future breeding programmes.