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Flood-generated hyperpycnal flows are dense, sediment-laden, turbulent flows that can form long-lived, bottom-hugging turbidity currents, which undoubtedly transport large volumes of fine-grained sediments into the ocean. However, their ability in transferring sand into deep-water basins is debated. This study presents sedimentological evidence of sandy hyperpycnal flow deposits (hyperpycnites) in a series of basin floor lobe complexes associated with a progradational shelf margin in the Eocene of Spitsbergen, Arctic Norway. Four coexisting types of sediment gravity flow deposits are recognized: (i) sandy hyperpycnites deposited by quasi-steady hyperpycnal flows; (ii) turbidites deposited by waning, surge-type turbidity currents; (iii) hybrid event beds deposited by transitional flows; and (iv) mass transport deposits emplaced during rare slope failures. The abundance of thick-bedded massive sandstones, frequent bed amalgamation, the distribution of hyperpycnites across the lobes and the abundance and systematic occurrence of plant-rich hybrid event beds and associated climbing ripple cross-laminated beds in the lobe fringes, suggest that hyperpycnal flow was the most important mechanism driving lobe progradation. Shelf-edge positioned fluvial channels linked to the basin floor lobe complexes via deeply incised, sandstone-filled slope channels, suggest that rivers fed directly onto the slopes where their dense, sand-laden discharges readily generated quasi-steady hyperpycnal flows that regularly reached the basin floor. The composite architecture and complex waxing–waning flow facies configuration of the hyperpycnites is consistent with sustained and concomitant suspension and traction deposition under fluctuating subcritical to supercritical conditions. Similar sandstone beds occur on the clinoform slopes, indicating that the hyperpycnal flows operated likewise on the slope. Plant-rich hybrid event beds indicate transformation of initially turbulent flows by relative enrichment of clay and plant material via progressive sand deposition to such an extent that it suppressed turbulence. The multi-faceted character of the hyperpycnites reported here, challenges traditional beliefs that hyperpycnites assumingly preserve the waxing–waning signal of single-peaked floods.

Understanding how sedimentary rocks represent time is one of the significant challenges in sedimentology. Sedimentation rates retrieved from vertical sections are strongly timescale dependent, which means that we cannot use empirical rate data derived from vertical sections in modern environments to interpret the temporal structure of ancient sedimentary deposits. We use the Lower to Middle Campanian Blackhawk Formation deposits in eastern Utah and western Colorado as a natural laboratory to test a source-to-sink methodology circumventing this timescale dependence by relating modern progradation rates to the deltaic shoreline progradation of ancient siliciclastic rocks. Our objective is to quantify how much time is needed to account for the observed cumulative deltaic shoreline progradation recorded by the shallow-marine sandstone bodies of the Blackhawk Formation in terms of progradation rates derived from comparable modern deltaic systems. By making the simplifying assumption that the Blackhawk Formation rocks were deposited along a linear coastline that only grew by aggradation and progradation, it is possible to argue that the stratigraphic completeness of two-dimensional dip-oriented stratigraphic cross-sections through these deposits should be high. Furthermore, we hypothesise that delta progradation estimates capture a significant portion of the biostratigraphically and radiometrically constrained duration of the succession. By comparing the recorded progradation with modern progradation rates, we estimate that we need ca. 20% (median value, with minimum and maximum estimates of 2% and 300%) of the time available from biostratigraphic and radiometric dating to account for the progradation recorded by the sedimentary deposits. This indicates that long-term progradation rates averaged over the entire duration of the Blackhawk Formation were only a factor of five times slower than the modern progradation rates derived from observations over periods that are five to six orders of magnitude shorter. We conclude that a significant amount of time is represented by prograding deltaic shoreline deposits and that by considering the cumulative shoreline progradation, we could limit the effects of timescale dependence on the rate estimates used in our analysis. publishedVersion

DNA polymerases have evolved to feature a highly conserved activity across the tree of life: formation of, without exception, phosphodiester linkages that create the repeating sugarphosphate backbone of DNA. Can this linkage selectivity observed in nature be overcome by design to produce non-natural nucleic acids? Here, we report that structure-guided redesign of an archaeal DNA polymerase (9°N) enables a new polymerase activity that is undetectable in the wild type enzyme: catalyzing the formation of N3’→P5’ phosphoramidate linkages in the presence of 3’-amino-2’,3’-dideoxynucleoside 5’-triphosphate (3’-NH2-ddNTP) building blocks. Replacing a highly conserved metal-binding aspartate in the 9°N active site (Asp-404) with asparagine was key to the emergence of this unnatural enzyme activity. Molecular dynamics simulations provided insights into how a single substitution could enhance the productive positioning of the 3’-amino nucleophile in the active site. Further remodeling of the protein-nucleic acid interface with substitutions in the finger subdomain led to a quadruple-mutant variant (9°N-NRQS) that incorporated 3’-NH2-ddNTPs into a 3’-amino-primer on various DNA templates. This work presents the first example of an active-site substitution of a metal-binding residue that leads to a novel activity in a DNA polymerase, and sheds light on the molecular basis of substrate fidelity and latent promiscuity in enzymes.

Teachers often group students into teams to organize their classrooms and network-informed interventions hold great promise as a way to facilitate positive peer influence and promote the diffusion of intervention effects. Yet thus far, relatively little research has explored how teachers or prevention scientists can best use social network information to assign students to teams. The goal of the present study was to identify and compare seven methods that use different data sources and assignment algorithms to create teams of students. To test these methods, we used survey data from 247 5th through 8th grade students in three rural schools that assessed students' social networks, sociability, values and interests, and bonding to school. To create teams, we first identified popular students (i.e., those who received the highest number of peer nominations) who also had school bonding scores in the normal range and formed 4-person teams around them, applying different methods to assign students to teams. In all but one method, we placed at-risk students (i.e., those who had the lowest school bonding scores) in teams only during the final round of team creation. Team assignments were compared against three criteria: (1) team-level bonding to school, (2) patterns of affiliation among teammates, and (3) shared values and interests. Two methods, one that used only social network data and one that used social network data in combination with students' values and interests, yielded the most promising outcomes. The most positive results were obtained when a pruning algorithm akin to the one proposed by Girvan and Newman (2002) Proceedings of the National Academy ofSciences, 99, 7821-7826 was used to select which dyads to join as teammates; this pruning method joined more weakly linked students first, maximizing their potential to find suitable matches. These methods for team assignment hold promise for designing network-informed school-based interventions.

This chapter builds on Hansen and Scheier by further examining the intersection of game-based learning and digital health promotion apps. The intersection of digital technology and health promotion is an intriguing space given that cost-effective technologies backed by strong theory and implementation science can advance health promotion strategies. Gamification extends asynchronous computer-mediated communication by creating a sense of immersion in the virtual space, socially interacting, and experiencing strong social identifications. This produces feelings of “flow” reported as a stoppage of time and mitigating surrounding intrusive events. Avatars provide pedagogical supports to increase situational awareness, deepening their presence in the digital game world. Players can learn from these interactions, building rapport and developing social connections that might otherwise not be possible in different contexts. Gamified digital technology capitalizes on instructional technology, learning theory, and social identification in ways that can advance health behavior change.

We normalized, harmonized, and pooled 344,429 surveys collected from 106,470 research participants from 25 research studies that assessed past 30-day alcohol use, drunkenness, smoking cigarettes, using marijuana, and a host of psychosocial variables. After normalizing and harmonizing psychosocial measures, we completed analyses to examine the ability of psychosocial variables to serve as proxy indicators of use. Intentionality, peer descriptive normative beliefs, and age emerged as being of primary importance in indicating use. Additional variables – peer injunctive norms, beliefs about the positive and negative consequences of use, and attitudes – were also demonstrated to have the potential to serve as proxies in the assessment of substance use risk. There were developmental patterns in how intentionality and descriptive normative beliefs changed with age. Young adolescents had scores that are protective; they have positive intentionality and do not see the prevalence of alcohol and other drug use as widespread. These and other psychosocial variable’s mean scores generally erode with age while the distribution of scores widens as youth grow older. The goal of analyses was to define age-related psychosocial profiles that can be used prospectively to estimate substance use risk. These profiles are useful in creating virtual control cases for evaluating disseminated prevention programs.

This paper argues that the aggressive and gratuitously violent insurgency in northeastern Nigeria – Boko Haram – is the entirely understandable consequence of more than a half-century of misrule by...

[Abstract This special issue dealing with the recent advances on modern and ancient clinoform‐stratified sedimentary successions arises from a European Geoscience Union (EGU) session “Clinoform drivers and stratigraphic products in siliciclastic and carbonate successions”, Vienna, April 2018. Clinoforms and clinothems represent a dominant architectural style of strata in many sedimentary environments, including deltaic and nondeltaic shorelines in both marine and lacustrine settings, and are one of the key building blocks of the sedimentary record. This Special Issue in Basin Research aspires to represent a step forward in understanding formation and preservation of these fundamental stratigraphic elements. As this Special Issue documents, a comprehensive understanding of clinoformal strata requires a multidisciplinary and multi‐scale approach. Sixteen papers present case studies from a variety of tectonic settings worldwide, investigated with an array of methods, including seismo‐stratigraphy, well logs, cores, high‐resolution biostratigraphy, outcrop studies and modern bathymetric data. While observations document sedimentary processes and products in sedimentary basins, numerical models are necessary to provide a quantitative basis for the extrapolation of these processes and strata at different temporal and spatial scales. The papers highlight at least five main research avenues that we briefly introduce and discuss below: (a) clinoforms and clinothems as sedimentary archives; (b) the nested nature of clinoformal strata and implications for the trajectory of the rollover point(s); (c) quantitative clinoform parameters and dynamic indices; (d) architecture, growth and sequence stratigraphy of marine versus lacustrine clinoformal strata; and (e) clinoforms and geological time. This introduction also contains brief descriptions of each paper of the Special Issue., Clinoforms and clinothems represent the dominant architectural style in many sedimentary basins and are widely recognized as one of the fundamental building blocks of the stratigraphic record. ]

[Abstract Clinoforms are basinward‐dipping and accreting palaeo‐bathymetric profiles that record palaeo‐environmental conditions and processes; thus, clinothems represent natural palaeo‐archives. Here, we document shelf‐edge scale clinoform sets which prograded through the entire width of an epicontinental marine basin (ca. 400 km), eventually encroaching onto the opposite basin flank, where they started to prograde upslope and landward, in defiance of gravity (“upslope‐climbing clinoforms”). The giant westward‐prograding Eridanos muddy shelf‐edge clinothem originated from the Baltic hinterland in the Oligocene and achieved maximum regression in the Early Pleistocene, on the UK Central Graben (CG) and Mid North Sea High (MNSH), after crossing the whole North Sea mesopelagic depocentre and causing near complete basin infill. Here we integrate well and seismic data through the MNSH and CG and examine the Eridanos final heyday and demise, identifying five clinothem complexes (A1, A2, A3, B and C) and six depositional sequence boundaries (SB1 to SB6) in the Miocene‐Recent section. Tectonic and climatic events drove the recent evolution of this system. Early Pleistocene climate cooling, in particular, resulted in a stepwise increase in sediment supply. This climaxed in the earliest Calabrian, following a likely Eburonian eustatic fall (=SB3) when the Eridanos clastic wedge was restructured from a 100–300 m thick compound shelf‐edge and delta system to a “hybrid” shelf‐edge delta at sequence boundary SB3 (ca. 1.75 Ma). In the ca. 40 kyr that followed SB3, a progradation rate peak (>1,000 m/kyr) is associated with clinoforms starting to accrete upslope, onto the east‐dipping slope between CG and MNSH. This “upslope‐climbing clinoform” phase was quickly followed by the maximum regression and final retreat of the Eridanos system in the Early Calabrian (=SB4), likely as the result of climate‐driven changes in the Baltic hinterland and/or delta auto‐retreat. To our knowledge, this contributions represents the first documentation of “upslope‐climbing clinoforms” recorded in the stratigraphic record., This article provides the first documentation of shelf‐edge clinoforms prograding landward and upslope (“upslope‐climbing clinoforms”). The upslope outbuilding of the Eridanos Shelf‐edge Delta took mainly place during an earliest Calabrian lowstand, possibly linked to Eburonian glacio‐eustasy. This architecture is due to high sediment supply combined with a pre‐existing regional depositional interface dipping ca. 0.12° contrary to the Eridanos progradation direction. ]

An appraisal of ancient Earth’s climate dynamics is crucial for understanding the modern climate system and predicting how this might change in the future. Major climate-shift events in the Earth’s past demonstrate the scale, duration and response of the climate system to various global and local climate stressors. More than 650 million years of deep-time paleoclimate changes are archived in the sedimentary succession of Svalbard; an archipelago located in the Norwegian High Arctic. The excellently outcropping geological successions of Svalbard date back to the Proterozoic, and record both temporal and spatial changing climatic and environmental conditions strongly linked to the northward continental drift of the archipelago from southern hemisphere in Precambrian to its present-day Polar latitudes.The oldest deposits that record major climatic events and associated environmental perturbations in Svalbard include tillites related to several Cryogenian glacial events and the overlying Ediacaran carbonates. The Lower Paleozoic succession documents episodes of marine biodiversification, including the Great Ordovician Biodiversification Event (GOBE), which is linked to cooling of previously warm tropical oceans. The arid to semi-arid climate of the Devonian promoted a terrestrial plant diversification. The Lower Carboniferous coal-bearing strata were deposited in humid and tropical climate settings prevailing in northern Pangea. The Upper Carboniferous-Lower Permian succession consists of interbedded carbonates, evaporites and red siliciclastics, including remains of paleokarst. The continued northward drift into subtropical latitudes promoted a change back to arid to semi-arid climates, occurring during the overall global icehouse conditions. During the Late Permian, marine sponges were occupying most of the ecological niches, leading to the deposition of weathering-resistant spiculites. But these ecosystems were rapidly and dramatically impacted by the End Permian Mass Extinction (EPME), which lasted well into the Early Triassic.By the Mesozoic, Svalbard was approaching mid-latitudes. The exposed in Svalbard deposits of Triassic mega-delta features evidence for a temperate or humid climate, indicated by thick coal beds that transitioned to an arid climatic environment at the end of the Triassic and Early Jurassic succession with caliche and calcareous soil profiles. The Lower Cretaceous strata (deposited at c. 66 °N) record several cold snaps despite the overall greenhouse climate characterizing the period and most notably the global crisis associated with the Aptian oceanic anoxic event 1a (OAE1a).By the Paleogene, Svalbard had reached Arctic latitudes, and as characterised by overall moderate to warm temperate climate, punctuated by warming episodes, including the Palaeocene–Eocene Thermal maximum (PETM). The Neogene cooling is missing from onshore records, but high-resolution glacial climate evidence exists offshore and from geomorphology and unconsolidated strata of Late Quaternary-Holocene age.In this contribution, we synthesize former and ongoing studies of deep-time paleoclimate in Svalbard and provide knowledge gaps to optimize the use of Svalbard as an archive for deep-time paleoclimate research. The exceptional exposures, accessibility, and completeness of the 650 million long sedimentary records makes Svalbard unique archive for deep-time paleoclimate research. In addition to Svalbard’s excellent outcrops, fully cored research and coal exploration boreholes provide an excellent foundation for further research with minimal environmental consequences.

In response to a need to implement an evidence-based prevention program, D.A.R.E. America adopted keepin’ it REAL. The program was previously developed and tested in middle school settings. As part of its adoption, an elementary version of the program was developed. This study tests the effectiveness of keepin’ it REAL when delivered to fifth graders. The intervention was delivered to two cohorts of students, the first in the 2019–2020 school year, the second in the 2020–2021 school year. Pretest surveys were completed by 6,122 students. The COVID-19 pandemic interfered with posttest and follow-up data collection. At immediate posttest, 2,049 students (33.5%) completed analyzable posttest surveys. One year after the pretest, 1,486 (24.3%) students completed usable follow-up surveys. We used algorithmically generated cases (virtual controls) that use treatment cases’ pretest psychosocial scores to assess program effectiveness. When compared to virtual control cases, the program had identifiable improvements in both a key psychosocial measure and in terms of deterring the onset of 30-day alcohol use, drunkenness, and vaping. Outcomes suggest that the delivery of elementary school keepin’ it REAL by D.A.R.E. officers is having a positive effect in terms of deterring the onset of alcohol use and vaping.

Purpose Alcohol, tobacco, marijuana and other drugs use typically increases in prevalence and frequency during middle and late adolescence. School health instruction often focusses on providing facts and rarely provides tools for addressing the psychosocial risk factors needed to prevent substance use. The purpose of this paper is to report about the effectiveness of a prevention programme delivered in US high school health classes. The intervention augments typical instruction by providing teachers with activities that can be infused in their daily teaching. Design/methodology/approach In total, 26 schools were randomly assigned to receive the intervention or serve as controls. Pupils were pretested near the beginning of the school year, posttest near the end of the school year and administered a final test near the beginning of the following school year. Teachers in treatment schools were provided with activities designed to target psychosocial variables known to mediate substance use onset and self-initiated cessation. These include normative beliefs, intentionality, lifestyle incongruence, beliefs about consequences of use, peer pressure resistance skills, decision-making skills, goal setting skills and stress management skills. Findings Hierarchical modelling analytic strategies revealed the intervention to have definable positive impacts on alcohol and cigarette use. Moreover, the intervention had strongest effects on alcohol and cigarette use among pupils who were identified at pretest as being lower-than-average risk. Originality/value This research provides support for providing teachers with a strategy for preventing alcohol, tobacco and other drugs that can be used in a flexible manner to augment the instruction they are already mandated to provide.

Delta plains host heavily populated and extensive agricultural areas with strong anthropogenic overprints on the natural evolution of these important landforms. Furthermore, modern delta plains have formed over a short geological time frame, representing immature end members to ancient counterparts in Earth’s history—it could thus be argued that these are poor analogues for deciphering the sedimentary rock record. Our present study offers unique insight into the controls and potential extent of ancient deltas by investigation of the Triassic Boreal Ocean, where a large delta plain has been traced across >1.65 × 106 km2. We show by comparison that the Triassic Boreal Ocean delta plain is larger than all modern and known ancient counterparts. Supply-driven progradation of this delta system proceeded uninterrupted on a 106 yr scale, indicating relative sea-level stability during this period—in support of a Triassic Greenhouse without pronounced glaciations. Reconstructed paleo-bathymetric relief shows the Triassic Boreal Ocean to have been one order of magnitude smaller than modern equivalents, explaining its vast extent. Despite its extent, the delta plain shows similar geomorphological characteristics to many modern delta plains, supporting their validity as analogues to the ancient, although scales might vary significantly. publishedVersion

Each year vast international resources are wasted on irreproducible research. The scientific community has been slow to adopt standard software engineering practices, despite the increases in high-dimensional data, complexities of workflows, and computational environments. Here we show how scientific software applications can be created in a reproducible manner when simple design goals for reproducibility are met. We describe the implementation of a test server framework and 40 scientific benchmarks, covering numerous applications in Rosetta bio-macromolecular modeling. High performance computing cluster integration allows these benchmarks to run continuously and automatically. Detailed protocol captures are useful for developers and users of Rosetta and other macromolecular modeling tools. The framework and design concepts presented here are valuable for developers and users of any type of scientific software and for the scientific community to create reproducible methods. Specific examples highlight the utility of this framework and the comprehensive documentation illustrates the ease of adding new tests in a matter of hours.

[Abstract A synthesis has been undertaken based on regionally compiled data from the post early Eocene foreland basin succession of Svalbard. The aim has been to generate an updated depositional model and link this to controlling factors. The more than kilometer thick progradational succession includes the offshore shales of the Gilsonryggen Member of the Frysjaodden Formation, the shallow marine sandstones of the Battfjellet Formation and the predominantly heterolithic Aspelintoppen Formation, together recording the progressive eastwards infill of the foredeep flanking the West Spitsbergen fold‐and‐thrust belt. Here we present a summary of the paleo‐environmental depositional systems across the basin, their facies and regional distribution and link these together in an updated depositional model. The basin‐margin system prograded with an ascending shelf‐edge trajectory in the order of 1°. The basin fill was bipartite, with offset stacked shelf and shelf‐edge deltas, slope clinothems and basin floor fans in the western and deepest part and a simpler architecture of stacked shelf‐deltas in the shallower eastern part. We suggest a foredeep setting governed by flexural loading, likely influenced by buckling, and potentially developing into a wedge top basin in the mature stage of basin filling. High‐subsidence rates probably counteracted eustatic falls with the result that relative sea‐level falls were uncommon. Distance to the source terrain was small and sedimentation rates was temporarily high. Time‐equivalent deposits can be found outbound of Stappen High in the Vestbakken Volcanic Province and the Sorvestsnaget Basin 300 km further south on the Barents Shelf margin. We cannot see any direct evidence of coupling between these more southerly systems and the studied one; southerly diversion of the sediment‐routing, if any, may have taken place beyond the limit of the preserved deposits., The Svalbard Eocene‐Oligocene (?) foreland basin succession. Upper left: facies‐scale depositional elements; upper right: mountainside‐scale of depositional geometries; lower: basin‐scale reconstruction with linkage of depositional systems. ]

[The BQART formulais an empirical relationship between observed total suspend sediment load (Tss) and catchment area (A), relief (R), temperature (T), water discharge (Q) and erodibility (B) in modern river systems. Application of the method for anancient S2S mass budget study requires: (1) an assessment of the methods suitability, (2) a paleogeographicreconstruction, (3) a paleoclimate reconstruction and (4) Monte Carlo simulations. , Abstract Constraining the timing and volume of sediment dispersal in an ancient sedimentary system is vital to understand a basin's infill history. One preferred method for a first‐order approximation of ancient sediment load estimates, the BQART model, is based on empirical observations of modern river systems relating basin morphology, topography, climate, run‐off and bedrock characteristics. Despite the popularity of such methods, a comprehensive assessment on the validity of using modern river observations to measure sediment load on geological timescales is lacking. Here, we investigate the uncertainties, sensitivities and practicalities surrounding the use of modern empirical observations in general and the BQART model in particular, to evaluate ancient sediment river loads. Although catchment area and relief are the least constrained parameters in an ancient sedimentary system, the temperature parameter may have an even more significant impact in the range of predicted sediment load estimates using a BQART approach. The applicability of BQART is most suitable for regional to continental scale source‐to‐sink systems that are based on robust paleogeographic and paleoclimatic models of cold ( 8°C) climates. One further needs to consider the high amplitude discharge events that can dominate the stratigraphic record which are not captured by historical observations of sediment load over a 30‐year period. In addition, our limited understanding of bedload material transport and an unknown pristine environment in the Anthropocene reduce the reliability of modern sediment load estimates for the ancient. Mass budget estimates in deep time based on empirical relationships of modern river systems can thus provide first‐order estimates within an order of magnitude but need to consider the limitations imposed by extrapolating the modern to the ancient. Here, we present a framework to consider the suitability of the BQART method for ancient source‐to‐sink mass budget analyses.]

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Numerous studies emphasize the role of student engagement in academic learning and performance. Less known is whether engagement plays a role in drug prevention program outcomes. We examined a self-report measure of engagement as part of the All Stars Core drug prevention program evaluation, assessing its impact on target risk mechanisms and behavioral outcomes. Students completed pretests just prior to and posttests just after completing the intervention. Surveys assessed demographics, proximal intervening measures (i.e., commitments to avoid substance use and antisocial behavior, perceived lifestyle incongruence with substance use and antisocial behavior, normative beliefs about substance use and antisocial behavior, and parental attentiveness), and distal outcome measures of alcohol, cigarette use, and antisocial behaviors. A brief 6-item posttest measure including items tapping the students’ perspective on the quality of teaching the program material and their level of engagement with the program was internally consistent (α = .79). Multi-level analyses positing engagement effects at both the classroom- and individual-level indicated that classroom average engagement was significantly associated with all the targeted risk mechanisms, and outcomes of antisocial behavior and alcohol use, controlling for pretest measures and classroom size. Individual student engagement relative to classroom peers was significantly associated with all posttest target risk mechanisms and behavioral outcomes. The current findings suggest that students should routinely provide assessments of engagement and perceived quality of teaching, which would improve our understanding of how prevention programs work. Teachers can improve engagement by paying attention to students when they speak in class, making the program enjoyable to participants, encouraging students to share opinions, stimulating attentiveness, being well prepared to deliver the intervention, and helping students think broadly about implications of drug prevention as it affects their lives. This type of support will ultimately engage students in ways that will enhance the likelihood that these programs will have their desired effects.

The design of protein-based assemblies is an emerging area in bionanotechnology with wide ranging applications, from vaccines to smart biomaterials. Design approaches have sought to mimic both the topologies of assemblies observed in nature, as well as their functionally relevant properties, such as being responsive to external cues. In the last few years, diverse design approaches have been used to construct assemblies with integer-dimensional (e.g. filaments, layers, lattices and polyhedra) and non-integer-dimensional (fractal) topologies. Supramolecular structures that assemble/disassemble in response to chemical and physical stimuli have also been built. Hybrid protein-DNA assemblies have expanded the set of building blocks used for generating supramolecular architectures. While still far from reproducing the sophistication of natural assemblies, these exciting results represent important steps towards the design of responsive and functional biomaterials built from the bottom up. As the complexity of topologies and diversity of building blocks increases, considerations of both thermodynamics and kinetics of assembly formation will play crucial roles in making the design of protein-based assemblies robust and useful.

Western Norwegian fjord-valley systems represent archives of changes in sedimentary processes, and typically exhibit a pronounced change in depositional environment related to the transition from glacial to interglacial conditions. During a glacial situation, the fjord-valley system is emptied of its sediments, indicating that most sediments present in the fjord today, was deposited during and after the retreat of the last deglaciation. The purpose of our investigations is to gain a better understanding of the volumes and frequencies of mass transport deposits (subaquatic mass movements such as mass flows, debris flows, slides, slumps, and turbidites) in a recently glaciated fjord-valley system since the deglaciation (approx. 11 700 years BP) by looking at Fjærlandsfjorden, a tributary fjord of Sognefjorden in western Norway. The fjord-valley system consists of steep hillslopes and deep fjord basins with reliefs of up to 1600 meters. Jostedalsbreen, the largest glacier on mainland Europe (ca. 473 km2), currently feeds into the catchment of the fjord basin.Here we present results from a cruise with R/V G.O. Sars in 2018, where sediment cores, TOPAS seismic profiles and bathymetric data were collected from Fjærlandsfjorden. The integration of high-resolution seismic (Seismic data reveal that the Fjærlandsfjorden basin infill consists of basal till, overlain by a thick, acoustically well-laminated glacimarine unit (up to a maximum thickness of ~105 meters thickness), occasionally disrupted by acoustically transparent lenses interpreted to be mass transport deposits (rock avalanches and debris flows). A 2-3 m thick hemipelagic unit drapes the glacimarine unit. Results reveal that ~90 % of the total sediment volume within the fjord basins was deposited as meltwater plumes during the retreat (mainly calving along the fjord) of the margin of the last glacial ice sheet. The retreat began at the mouth of Sognefjorden at the termination of the Younger Dryas Chronozone around 11 700 cal. yrs BP, to a frontal position at the head of Fjærlandsfjorden around 10 700 cal. yrs BP. The remaining volume of sediments are divided into mass transport deposits (MTDs) such as avalanches, debris flows, and flood-related turbidites as well as hemipelagic sedimentation. The largest MTD is a massive rock avalanche measuring up to 5 million m3 that most likely caused a large tsunami when it occurred.

Catchments provide water and sediment to downstream sedimentary systems, and these form individual source-to-sink systems. Source-to-sink systems comprise adjacent linked segments, commonly hinterland catchments, alluvial- and coastal plains, the continental shelf, continental slope and submarine fan. The dimensions of the catchment and how it scales to downstream segments provides insight into the sedimentary and tectonic controls that influence the morphology and sedimentation patterns in a basins evolution. In ancient sedimentary successions, where the sedimentary routing system is buried and inaccessible for study, or fragmented due to uplift and erosion, using scaling relationships can provide a powerful tool to understand the complete sedimentary system. Observational data from modern sedimentary systems provide an opportunity to create morphological and sedimentological scaling relationships of segments on the entire source-to-sink system. However, previous studies on global modern source-to-sink systems have typically been based on a limited number of examples restricted by the data available at the time and the methodology used to analyze large datasets. In the last decade, the volume and quality of remotely sensed information has significantly improved so that it is now timely to revisit scaling relationships of modern source-to-sink systems' segment morphologies, and discuss the implications of those r esults for sedimentological parameters and applicability to ancient source-to-sink systems. The results of this reanalysis show that dimensions of the catchment and submarine fan segments scale internally in terms of fan width, length and area. In addition, fan area scales to its largest hinterland catchment area in agreement with previous studies, however, it is important to consider all catchments that contribute sediment to a basin floor region. In paleogeographic settings, where individual submarine fans are difficult to tie to a single catchment, and where basin floor systems are amalgamated, the contributing sediment discharge of all catchments may be significant and likely influence the scale of its submarine fan. Accommodation versus sediment supply in relation to relative sea level change are important controls on the position of the shoreline which vary considerably from system to system over time and space, thus influencing morphological relationships between source-to-sink segments. The continental shelf should therefore be viewed as a transient geomorphic feature rather than a segment of a source-to-sink system. Furthermore, the continental slope length should not be used to scale other segments of the source-to-sink system, which contradicts previous research. The underlying tectonic and sedimentological control on the continental shelf and slope segments, in addition to the subjective interpretation of their basinward boundaries, may render those segments unsuitable for scaling the morphology of other segments. The study highlights both the temporal variability and complexity of controls that influence the morphology and scaling relationships of internal and adjacent linked source-to-sink segments, and the need to place this in a framework of both tectonic and sedimentological history.

Empirical rate data show that aggradation and progradation rates are negatively correlated with the duration they are averaged over. This means that we cannot understand deep time sedimentation rates in terms of the abundant rate data we have from modern environments. We are addressing this by investigating how growth of a sediment volume in multiple directions affects time-averaged accumulation rates that do not necessarily measure all directions of growth. We derive a mathematical model from mass-balance considerations of a sedimentary deposit that grows without erosion. We show that the non-linear relationship between the lengths, areas and volumes of growing objects require that time-averaged sedimentation rates are time-scale dependent when a deposit grows in multiple directions. We generate rate compilations from simple synthetic stratigraphies, which show that we can reproduce the empirical rate compilations by requiring only that deposition occur in a dynamic mosaic of sequential patches in which the areal extent of deposition increases with time-scale as described by our mathematical model. Our model has two implications with application in stratigraphic analysis. The first is that it provides a theoretical model of why we cannot expect high stratigraphic completeness if we measure a deposit in fewer directions than it has grown. The second is that it provides a framework by which to attribute anomalies in the stratigraphic completeness of a one-dimensional or two-dimensional sample to scaling effects or erosional hiatuses.

The South Lake Albert Basin (SLAB) is part of the Albertine graben , the northernmost part of the western arm of the East African Rift System (EARS). The study focused on interpretation of three-dimension (3D) seismic and suites of wireline log datasets, construction of 3D models, facies analysis , surface geological mapping and integrating both subsurface and surface data to assess reservoir rock properties. From previous studies, low to moderate reservoir quality (porosity, permeability and Vshale) was realized, and most of the drilled wells encountered two or more separate stacked oil accumulations (complex reservoirs) whose lateral extent had not been well understood and that was attributed to poor reservoir property distribution. The major aim of this study is to quantify the reservoir rock properties and integrating both subsurface and surface data in order to evaluate the reservoir property distribution within the study area, with specific objectives of (1) interpreting subsurface and facies modelling data and (2) to conduct field (surface) data sampling, analysis and interpretation (3) integrating both subsurface and surface data. From the obtained results, it was deduced that the lithology from facies modelling (subsurface results) and field geological mapping (surface results) data and the reservoir rock properties in both Kaiso Tonya and Kingfisher areas generally had moderate to good values for all the interpreted reservoir rock properties that were quantified however, the section under Lake Albert had better results. In addition, the reservoir rock properties for both subsurface and surface data were changing at very short intervals with intercalations of clay, silt, fine and coarse sands that was attributed to short changes in climatic (wet and dry) conditions that happened over time during the sedimentation process. It was further deduced that sediment compartmentalization and intercalation have effect on the reservoir rock properties.

The estimation and modeling of streambed hydraulic conductivity (K) is an emerging interest due to its connection to water quality, aquatic habitat, and groundwater recharge. Existing research has found ways to sample and measure K at specific sites and with laboratory tests. The challenge undertaken was to review progress, relevance, complexity in understanding and modeling via statistical and geostatistical approaches, literature gaps, and suggestions toward future needs. This article provides an overview of factors and processes influencing streambed hydraulic conductivity (K) and its role in the stream-aquifer interaction. During our synthesis, we discuss the influence of geological, hydrological, biological, and anthropogenic factors that lead to variability of streambed substrates. Literature examples document findings to specific sites that help to portray the role of streambed K and other interrelated factors in the modeling of hyporheic and groundwater flow systems. However, studies utilizing an integrated, comprehensive database are limited, restricting the ability of broader application and understanding. Examples of in situ and laboratory methods of estimating hydraulic conductivity suggest challenges in acquiring representative samples and comparing results, considering the anisotropy and heterogeneity of fluvial bed materials and geohydrological conditions. Arriving at realistic statistical and spatial inference based on field and lab data collected is challenging, considering the possible sediment sources, processes, and complexity. Recognizing that the K for a given particle size group includes several to many orders of magnitude, modeling of streambed K and groundwater interaction remain conceptual and experimental. Advanced geostatistical techniques offer a wide range of univariate or multi-variate interpolation procedures such as kriging and variogram analysis that can be applied to these complex systems. Research available from various studies has been instrumental in developing sampling options, recognizing the significance of fluvial dynamics, the potential for filtration, transfer, and storage of high-quality groundwater, and importance to aquatic habitat and refuge during extreme conditions. Efforts in the characterization of natural and anthropogenic conditions, substrate materials, sediment loading, colmation, and other details highlight the great complexity and perhaps need for a database to compile relevant data. The effects on streambed hydraulic conductivity due to anthropogenic disturbances (in-stream gravel mining, contaminant release, benthic activity, etc.) are the areas that still need focus. An interdisciplinary (hydro-geo-biological) approach may be necessary to characterize the magnitude and variability of streambed K and fluxes at local, regional scales.

The Early to Middle Jurassic Sto Formation (Toarcian to Bajocian) was deposited in a relatively shallow (10 s of meter deep) epicontinental sea in northern Pangea and represents one of the most prolific reservoir intervals in the Barents Sea basin. It comprises a condensed, predominantly shallow marine succession characterized by long hiatuses and erosional reworking with several horizons of extraformational pebble grade conglomerate. Six distinct facies associations describe sedimentological environments ranging from transgressive, tidal, fluvial and regressive shoreface. Deposits are interpreted and correlated within three sequence stratigraphic units (SI to SIII) which reflect variations in relative sea-level during an overall transgression of the basin. Interpreted depositional systems show subtle variations in petrographic character, but provenance analyses reveal different sedimentary sources. Thirteen core samples distributed geographically and stratigraphically were analysed for detrital zircon U-Pb geochronology. Data show that the Southwestern Barents Sea Basin (SWBSB) was dominated by mixing of reworked material and coarse grained sediment supply from extrabasinal source areas including a Caledonian provenance in the southwest and a Fennoscandian provenance to the southeast. Intra-basinal erosion of underlying strata with Triassic zircon grains dominate in northern parts of the basin. Supplementary material : Supporting information relating to the analysis of different dataset and the interpretations presented in the paper are available at https://doi.org/10.6084/m9.figshare.c.3841282.

This is the peer reviewed version of the following article: Jelby, M.E., Grundvåg, S.‐A., Helland‐Hansen, W., Olaussen, S. & Stemmerik, L. (2020). Tempestite facies variability and storm‐depositional processes across a wide ramp: Towards a polygenetic model for hummocky cross‐stratification. Sedimentology, 67, 742-781, which has been published in final form at https://doi.org/10.1111/sed.12671. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. The hydrodynamic mechanisms responsible for the genesis and facies variability of shallow‐marine sandstone storm deposits (tempestites) have been intensely debated, with particular focus on hummocky cross‐stratification. Despite being ubiquitously utilized as diagnostic elements of high‐energy storm events, the full formative process spectrum of tempestites and hummocky cross‐stratification is still to be determined. In this study, detailed sedimentological investigations of more than 950 discrete tempestites within the Lower Cretaceous Rurikfjellet Formation on Spitsbergen, Svalbard, shed new light on the formation and environmental significance of hummocky cross‐stratification, and provide a reference for evaluation of tempestite facies models. Three generic types of tempestites are recognized, representing deposition from: (i) relatively steady and (ii) highly unsteady storm‐wave‐generated oscillatory flows or oscillatory‐dominated combined‐flows; and (iii) various storm‐wave‐modified hyperpycnal flows (including waxing–waning flows) generated directly from plunging rivers. A low‐gradient ramp physiography enhanced both distally progressive deceleration of the hyperpycnal flows and the spatial extent and relative magnitude of wave‐added turbulence. Sandstone beds display a wide range of simple and complex configurations of hummocky cross‐stratification. Features include ripple cross‐lamination and ‘compound’ stratification, soft‐sediment deformation structures, local shifts to quasi‐planar lamination, double draping, metre‐scale channelized bed architectures, gravel‐rich intervals, ‘inverse to normal’ grading, and vertical alternation of sedimentary structures. A polygenetic model is presented to account for the various configurations of hummocky cross‐stratification that may commonly be produced during storms by wave oscillations, hyperpycnal flows and downwelling flows. Inherent storm‐wave unsteadiness probably facilitates the generation of a wide range of hummocky cross‐stratification configurations due to: (i) changes in near‐bed oscillatory shear stresses related to passing wave groups or tidal water‐level variations; (ii) multidirectional combined‐flows related to polymodal and time‐varying orientations of wave oscillations; and (iii) syndepositional liquefaction related to cyclic wave stress. Previous proximal–distal tempestite facies models may only be applicable to relatively high‐gradient shelves, and new models are necessary for low‐gradient settings.

We used detrital zircon fractions from the Late Triassic to Early Jurassic sedimentary succession in the Norwegian Barents Sea to constrain the role of eastern provenance areas in the basin infill history of the Northern Pangea Boreal basin. Geochronological data from sedimentary rocks in this succession reveal detrital zircon ages that are very close to the biostratigraphically defined maximum depositional age of the two lowermost intervals: The Norian to Rhaetian Fruholmen Formation show U-Pb minimum ages of 208.3 ± 4.2 Ma (discordant by -0.58) and 213.8 ± 5 Ma (discordant by 0.8), and the Rhaetian to Sinemurian Tubaen Formation is 200.6 ± 4.9 Ma (discordant by -3.99) at its minimum. These are the youngest ages thus far documented in the Norwegian Barents Sea, and they demonstrate that a provenance area was magmatically active while, or shortly before, these formations were being deposited. Such protolith ages have not been documented close to the study area, but based on the regional tectonic setting and paleogeography, we argue that the Novaya Zemlya protrusion of the northern Uralian orogen was the most likely provenance area in the region. The Sinemurian to Pliensbachian Nordmela Formation samples yielded, with an exception of a single detrital zircon age of 211 ± 4.3 Ma, a consistent 240–237 Ma minimum detrital zircon age, which suggests that either the magmatic activity or the sediment supply had come to an end by Sinemurian times. This turnover can be explained by a change in the hinterland drainage pattern. This study documents that eastern provenance areas were actively supplying sediments into the Norwegian Barents Sea Basin later than previously assumed, and our data offer age constraints for tectonic activity in the basin and its hinterland inferred from the changes in sediment supply to the basin.

Ice storms are severe meteorological events that often result in damage to forested areas in the mid-latitudes. On 11 December 2008, an ice storm affected northern New York and New England and caused extensive damage to forested areas. We examined topographical and biological factors influencing the spatial distribution of forest damage due to the 2008 ice storm. We assessed 57 forest plots in 7 locations. Forest impacts from the storm were highly variable across the study area. Analysis of genera indicated that Prunus (cherry), Fraxinus (ash), Fagus (beech), and Acer (maple) were particularly susceptible to damage, while Tsuga (hemlock), Pinus (pine), and Carya (hickory) were more resistant. Elevation, latitude, and topographic exposure to post-storm winds after ice-loading were the dominant factors influencing damage levels.

Production, transport, and deposition of siliciclastic sediments takes place across changing altitudes, physical processes, environments, and controls en route from source to sink commonly through a downstream narrowing and then broadening fairway of sediment grains, constituting giant “hourglasses” of nature, a fundamental unit of both geomorphology and sedimentology. Here we review the status of the rapidly evolving multidisciplinary source-to-sink approach, and compare it with the more mature sequence stratigraphic approach. The latter uses outcrop, well, and seismic data to gain information about elements of basin fills with less data coverage and is thus mainly a “sink-to-sink” approach. Source-to-sink on the other hand aims to understand the dynamics and budgets of the complete onshore–offshore sediment fairway, including elements of the transect that are no longer preserved. Furthermore, we summarize the spatial and temporal variability of source-to-sink systems, and discuss qualitative and semiquantitative methods for reconstruction of area, relief, and sediment supply from source terrains. The variability of source-to-sink systems is viewed in the framework of three end-member types, “steep, short, and deep,” “wide and deep,” and “wide and shallow,” where each is characterized by typical patterns of sediment partitioning and long-term preservation. Modern and sub-modern systems are keys to enhance our understanding of their ancient counterparts. Three different time-framework categories for source-to-sink analysis are presented: modern systems, pre-modern Quaternary systems, and pre-Quaternary systems, all of which have large differences when it comes to amount and type of data, controlling factors, accuracy in interpretation, and societal applications. Importantly, systems are evolving through time with the effect that estimations of source-area parameters for one period of time may change significantly into another when boundary conditions are different. Sink reconstruction can, with variable confidence, be established through the use of seismic-reflection, well, and outcrop data, whereas reconstruction of source relief, drainage, and sediment production is a more challenging task. Methods like landscape interpolation, sediment volume backfilling, geomorphological scaling relationships, sediment-load estimations from river data and from stratigraphy as well as geochemical data can, preferably in combination, be used to unravel past source terrains. These methods are presented along with a discussion on how they can improve models for basin fill. Sink and source reconstruction is a two-way process. Source reconstruction sheds light on sink understanding and vice versa. This integrated approach is a prerequisite for further advance in source-to-sink studies. The prognosis of source-area parameters may give additional insight into the complete erosional–depositional system in general and sediment supply in particular and hence enables us to arrive at more robust models and predictions for the sink where resources commonly are contained.

The evolution of depositional systems in multiphase rifts is influenced by the selective reactivation of faults between subsequent rift phases. The Middle Jurassic to Palaeocene tectonic history of the Lofoten margin, a segment of the North Atlantic rift system, is characterised by three distinct rift phases separated by long (>20 Myr) inter-rift periods. The initial rift phase comprised a distinct fault initiation and linkage stage, whereas the later rift phases were characterised by selective reactivation of previously linked through-going faults which resulted in immediate rift climax. Using 2-D and 3-D seismic reflection data in conjunction with shallow core data we present a 100 Myr record of shallow to deep marine depositional environments that includes deltaic clinoform packages, slope aprons and turbidite fans. The rapid re-establishment of major faults during the later rift phases impacts on drainage systems and sediment supply. Firstly, the immediate localisation of strain and accumulation of displacement on few faults results in pronounced footwall uplift and possible fault block rotation along those faults, which makes it more likely for any antecedent fault-transverse depositional systems to become reversed. Secondly, any antecedent axially-sourced depositional systems that are inherited from the foregoing rift phase(s) are likely to be sustained after reactivation because such axial systems have already been directed around fault tips. Hence, the immediate localisation of strain through selective reactivation in the later rift phases restricts fault-transverse sediment supply more than axial sediment supply, which is likely to be a key aspect of the tectonosedimentary evolution of multiphase rifts.

We present a compilation of modern shoreline progradation rates measured close to river outlets entering deltaic coastlines, and we discuss how these observations relate to the overall evolution of both modern and ancient deltaic coastlines. We analyzed Landsat‐derived satellite images to identify plan view changes in the subaerial morphology of 331 modern deltaic coastlines. Our rate compilation (km2/year) had a lognormal distribution with parameters μ = −1.85 and σ2 = 1.01. We found that the rate data could be predicted to within an order of magnitude by an empirically derived power law using only fluvial water discharge and suspended sediment load as input parameters (rpro=10-2.3Q0w59Q0s34). We justified this river‐centric model of our progradation rates by assuming that delta progradation rates measured close to river outlets were more reflective of fluvial processes than of basinal processes, and preliminary tests supported this assumption. Our rate compilation and empirical model could provide useful constraints to guide stratigraphic analysis of ancient source‐to‐sink systems and to build analog and numerical models.

Present-day catchments adjacent to sedimentary basins may preserve geomorphic elements that have been active through long intervals of time. Relicts of ancient catchments in present-day landscapes may be investigated using mass-balance models and can give important information about upland landscape evolution and reservoir distribution in adjacent basins. However, such methods are in their infancy and are often difficult to apply in deep-time settings due to later landscape modification. The southern Barents Sea margin of N Norway and NW Russia is ideal for investigating source-to-sink models, because it has been subject to minor tectonic activity since the Carboniferous, and large parts have eluded significant Quaternary glacial erosion. A zone close to the present-day coast has likely acted as the boundary between basin and catchments since the Carboniferous. Around the Permian-Triassic transition, a large delta system started to prograde from the same area as the present-day largest river in the area, the Tana River, which has long been interpreted to show features indicating that it was developed prior to present-day topography. We performed a source-to-sink study of this ancient system in order to investigate potential linkages between present-day geomorphology and ancient deposits. We investigated the sediment load of the ancient delta using well, core, two-dimensional and three-dimensional seismic data, and digital elevation models to investigate the geomorphology of the onshore catchment and surrounding areas. Our results imply that the present-day Tana catchment was formed close to the Permian-Triassic transition, and that the Triassic delta system has much better reservoir properties compared to the rest of Triassic basin infill. This implies that landscapes may indeed preserve catchment geometries for extended periods of time, and it demonstrates that source-to-sink techniques can be instrumental in predicting the extent and quality of subsurface reservoirs. publishedVersion

Fractal topologies, which are statistically self-similar over multiple length scales, are pervasive in nature. The recurrence of patterns at increasing length scales in fractal-shaped branched objects, e.g., trees, lungs, and sponges, results in high effective surface areas, and provides key functional advantages, e.g., for molecular trapping and exchange. Mimicking these topologies in designed protein-based assemblies will provide access to novel classes of functional biomaterials for wide ranging applications. Here we describe a computational design approach for the reversible self-assembly of proteins into tunable supramolecular fractal-like topologies in response to phosphorylation. Computationally-guided atomic-resolution modeling of fusions of symmetric, oligomeric proteins with Src homology 2 (SH2) binding domain and its phosphorylatable ligand peptide was used to design iterative branching leading to assembly formation by two enzymes of the atrazine degradation pathway. Structural characterization using various microscopy techniques and Cryo-electron tomography revealed a variety of dendritic, hyperbranched, and sponge-like topologies which are self-similar over three decades (~10nm-10μm) of length scale, in agreement with models from multi-scale computational simulations. Control over assembly topology and formation dynamics is demonstrated. Owing to their sponge-like structure on the nanoscale, fractal assemblies are capable of efficient and phosphorylation-dependent reversible macromolecular capture. The described design framework should enable the construction of a variety of novel, spatiotemporally responsive biomaterials featuring fractal topologies.One Sentence SummaryWe report a computationally-guided bottom up design approach for constructing fractal-shaped protein assemblies for efficient molecular capture.