Miracle-dz/UniFAR-FTUs huggingface dataset:
Pore‐scale simulation of density‐driven convection in fractured porous media during geological CO2 sequestration

Global warming is attributed to the excessive emission of greenhouse gases, one of whose main components is carbon dioxide (CO2). A promising long‐term solution for mitigating global warming is geological CO2 sequestration, which is the capture and storage of enormous amounts of CO2 in underground reservoirs in order to reduce CO2 build up in the atmosphere. In this study, a pore‐scale lattice Boltzmann method was used to simulate density‐driven convection in a porous medium with a fracture, to study geological CO2 sequestration in deep saline aquifers. The CO2‐brine interface was located at the top of the domain. Both fracture width and body force were varied to generate different Ra numbers in order to investigate the effect of Ra on the convection. All simulated data can be fitted by the same trend, implying that the characteristic length of the system was dominated by the fracture width. When Ra was high enough, increasing Ra did not reduce the critical time for the onset of instability apparently. Also, it did not increase the maximum peak vertical velocity noticeably. Therefore, there existed asymptotic values for the critical time and maximum peak vertical velocity. With high Ra numbers, the high‐frequency oscillation of turbulence greatly enhanced the dissolution of CO2 into brine. After the onset of convective instability, the brine with a high CO2 concentration intruded into the underlying unaffected brine, which increased the interfacial area between the CO2‐rich brine and unaffected brine, and consequently favored the migration of CO2 into the fracture and porous medium. This study is the first pore‐scale one investigating density‐driven convection during geological CO2 sequestration in deep saline aquifers, whereas most existing research is focused on the field scale and the dissolved CO2 concentration at the top boundary is usually assumed to be saturated.
Long-term behaviour of reconsolidated clay around a driven pile

Extensive in situ testing and undisturbed sampling were carried out near two steel piles to determine the long-term state of a clay in which these piles had been driven 7 years before. Results show that this material exhibits a rigidity that varies with the distance from the pile. The average rigidity in the zone of study is representative of a slightly destructured clay. The shear strength of this clay is, in most cases, equal to the shear strength of the intact material except in the zone located at depth greater than 3.5 m and within 30 cm of the pile wall, where lower shear strength values were consistently monitored. It is believed that reconsolidation after driving took place in this last case under relatively low stresses. Key words: piles, clays, ageing, destruction, reconsolidation, shear strength, rigidity, limit state.
Three-dimensional seismic geomorphology and analysis of the Ordovician paleokarst drainage system in the central Tabei Uplift, northern Tarim Basin, western China

High-quality three-dimensional seismic data acquired in the central Tabei Uplift, Tarim Basin, western China, provide a rare opportunity to characterize in exceptional detail the three-dimensional geomorphology of a deeply buried (5500–6500 m [18,045–21,325 ft]) Ordovician unconformity and the related paleokarst drainage system. An integrated approach was applied that emphasized integration of seismic data with available conventional core, wireline logs, and age-equivalent outcrops. The exceptional quality of the seismic data allowed a seismic detection limit of karstified features of less than 75 75 m (246 246 ft) horizontally and 6 m (20 ft) vertically. Interpreted geomorphologic and depositional elements include fluvial channels and canyons, fluvial valleys, sinkholes, and tower karsts and hills. The modern tower karst-drainage system in Guilin, China, is very similar to the mapped Ordovician karst-drainage system and is used as a modern analog. The interaction between the surface karst-drainage system and the shallow-subsurface cave-passage system is evidenced by the observation that surface canyons appear to initiate in areas associated with intense sinkhole development. Also, surface river valleys tend to correspond to dip-oriented surface depressions partly related to near-surface cave collapse. During burial into the deeper subsurface, the combination of intrastratal collapse (karstified strata) and suprastratal collapse (postkarst-deposited strata) created large damage zones hundreds of meters thick and kilometers wide. Coalesced-collapsed paleocave systems can be interpreted from the unique circular pattern of faults (observed in map view) that are associated with seismic bright spots.
Edinburgh Research Explorer Adolescents and self-taken sexual images

: Despite increasing public interest and concern about young people’s involvement in the self-production of sexual images (or ‘sexting’), there remains a dearth of research into their reasons for making and sending images, the processes involved, and the consequences arising from their experiences. This article reviews the motivational, lifestyle and personality factors influencing adolescent sexting practices and explores the research evidence within the wider context of debates around contemporary social and visual media cultures and gender. A systematic search of databases was conducted and eighty-eight records were identified for inclusion in the review. The findings reveal that sexting is remarkably varied in terms of context, meaning and intention, with the potential for consensual and non-consensual aspects of the activity. Whilst sexting can be a means of flirting or enhancing a sexual relationship, it can highlight potential vulnerabilities to victimisation or to participation in risky sexual practices. Sexting is also inextricably linked to social expectations of gendered sexual behaviours, with females often deriving less satisfaction from their experiences and being perceived more negatively by their peers. Further research linking adolescent motivations, well-being, relationships and lifestyles with the broader socio-cultural and media landscape will ultimately help drive understanding about the subject forward.
What Is the Thermohaline Circulation?

The term "thermohaline circulation" is widely used in the context of past and future climate change. In his Perspective, Wunsch argues that there are many different, and inconsistent, definitions for this term. He defines ocean circulation in terms of mass fluxes, which are largely driven by surface forces such as wind and tides, and argues that thermohaline circulation should only refer to the separate transport of heat and salinity in the ocean.
Rescue of alveolar wall liquid secretion blocks fatal lung injury by influenza-staphylococcal coinfection

Secondary lung infection by inhaled Staphylococcus aureus (SA) is a common and lethal event in individuals infected with influenza A virus (IAV). It is unclear how IAV disrupts host defense to promote SA infection in lung alveoli, where fatal lung injury occurs. We addressed this issue using the first real-time determinations of alveolar responses to IAV in live, intact, perfused lungs. Our findings show IAV infection blocked defensive alveolar wall liquid (AWL) secretion and induced airspace liquid absorption, thereby reversing normal alveolar liquid dynamics and inhibiting alveolar clearance of inhaled bacteria. Loss of AWL secretion resulted from dephosphorylation, hence inhibition of the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel in alveolar epithelium, and airspace liquid absorption was caused by alveolar epithelial stimulation of the epithelial Na+ channel (ENaC). Loss of AWL secretion promoted alveolar stabilization by SA and alveolar damage by the secreted SA toxin, alpha hemolysin, but rescue of AWL secretion protected against fatal SA-induced lung injury in IAV-infected mice. These findings reveal a central role for AWL secretion in alveolar defense against inhaled bacteria and identify AWL inhibition as a critical mechanism of IAV lung pathogenesis. AWL rescue may represent a new therapeutic approach for IAV-SA coinfection. GRAPHICAL ABSTRACT
AVHRR, MODIS, and VIIRS radiometric stability and consistency in SST bands

[1] Monitoring of IR Clear-Sky Radiances over Oceans for SST (MICROS; www.star.nesdis.noaa.gov/sod/sst/micros) is NESDIS near-real time web-based radiance monitoring system. It analyzes Model (Community Radiative Transfer Model, CRTM) minus Observation (M-O) biases in brightness temperatures (BT) in three bands centered at 3.7 (IR37), 11 (IR11), and 12 µm (IR12), for several AVHRR (NOAA-16, -17, -18, -19, Metop-A, -B), VIIRS (Suomi National Polar Partnership, S-NPP), and MODIS (Terra, Aqua) sensors. Double-differences (DD) are employed to check BTs for radiometric stability and consistency. All sensors are stable, with the exception of two AVHRRs, onboard NOAA-16 and to a lesser extent NOAA-18, and generally consistent. VIIRS onboard S-NPP, launched in October 2011, is well in-family, especially after its calibration was fine-tuned on 7 March 2012. MODIS M-O biases were initially out-of-family by up to −0.6 K, due to incorrect CRTM transmittance coefficients. Following MICROS feedback, CRTM Team updated coefficients and brought MODIS back in-family. Terra and Aqua BTs are very consistent in IR11 and IR12 but show cross-platform bias of 0.3 K in IR37, likely attributed to MODIS characterization. Work with MODIS Characterization Support Team is underway to resolve this. Initial analyses of AVHRR onboard Metop-B launched in September 2012 suggest that its BTs are offset from Metop-A by up to ∼0.3 K. Overall, MICROS DDs are well suited to evaluate the sensors stability, but dedicated effort is needed to ensure consistent radiative transfer modeling (RTM) calculations for various sensors before DDs can be used in Global Space-based Inter-Calibration System (GSICS) quantitative applications.
A Note on Submarine Ridges and Elevations with Special Reference to the Russian Federation and the Arctic Ridges

The Russian Federation's claim to the 2,500,000 km2 area of the Arctic continental shelf is based mainly on the inclusion of the Lomonosov and Mendeleev Ridges as part of the Russian continental margin. The UN Convention on the Law of the Sea does not clearly define differences between oceanic ridges and natural components of the continental shelf. The main burden of interpretation rests with the Commission on the Limits of the Continental Shelf. How the Commission deals with Arctic ridges will influence the scope of claims from all the other coastal states with adjacent ridges and natural components of the continental shelf.
Bias in seismic estimates of crustal properties

SUMMARY It has come to our attention that the least-squares estimator we proposed in a recent paper to recover bulk crustal P velocity, VP, and P velocity/S velocity ratio, R, of the crust from traveltimes of scattered teleseismic phases, is inconsistent. That is, in the presence of errors, estimates of R will be biased downwards and estimates of VP will be biased upwards from their true values. In this note we supply bias corrections for both quantities that depend upon an estimate of the variance in a ratio of traveltime sums, and demonstrate their validity through comparison with estimates based on a two-parameter grid search. Application to station HYB yields R = 1.756 ± 0.005, VP = 6.2 ± 0.1 km s −1 , after correction of a systematic traveltime picking error that had affected our previous results. In addition, we provide an alternative waveform-stacking approach that involves a 2-D grid search over R and VP followed by a 1-D line search over crustal thickness H. An estimate of the direct Ps conversion time is required, and results from station HYB are consistent with those produced using traveltimes alone.
The Subsurface Geology of the Meer Area in Forth Belgium, and its Significance for the Occurrence of Hydrocarbons

In North Belgium, unusually thick Namurian strata are shown to be related to the existence of a deep basin. The presence of a listric growth fault is demonstrated in the Upper Carboniferous, somewhat limiting the Namurian Basin. The associated roll-over structure may contain sandstones with sufficient porosity to become an attractive exploration target for gas.
The impact of helium on thermosphere mass density response to geomagnetic activity during the recent solar minimum

[1] High-resolution mass density observations inferred from accelerometer measurements on the CHAMP and GRACE satellites are employed to investigate the thermosphere mass density response with latitude and altitude to geomagnetic activity during the recent solar minimum. Coplanar orbital periods in February 2007 and December 2008 revealed the altitude and latitude response in thermosphere mass density for their respective winter hemispheres was influenced by the relative amount of helium and oxygen present. The CHAMP-to-GRACE (C/G) mass density ratio depends on two terms; the first proportional to the ratio of the mean molecular weight to temperature and the second proportional to the vertical gradient of the logarithmic mean molecular weight. For the relative levels of helium and oxygen in February 2007, the winter hemisphere C/G mass density response to geomagnetic activity, although similar to the summer hemisphere, was caused predominantly by changes in the vertical gradient of the logarithmic mean molecular weight. In December 2008, the significant presence of helium caused the mean molecular weight changes to exceed temperature changes in the winter hemisphere leading to an increase in the C/G ratio with increasing geomagnetic activity, in opposition to the decrease observed in the summer hemisphere that was caused primarily by temperature changes. The observed behavior is indicative of composition effects influencing the mass density response and the dynamic action of the oxygen to helium transition region in both latitude and altitude will lead to complex behaviors in the mass density at GRACE altitudes throughout the extended solar minimum from 2007 to 2010.
Did the 2011 Nabro eruption affect the optical properties of ice clouds?

The eruption of the Eritrean Nabro Volcano in June 2011 was the largest eruption since Mount Pinatubo in June 1991. The Nabro volcano emitted 1–1.5 megaton of sulfur dioxide into the lower stratosphere which resulted in a significant rise in the stratospheric sulfate aerosol burden in the months following the eruption. We have analyzed backscatter and extinction from ice clouds, as measured by the Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite between June 2006 and May 2014, to assess if volcanic aerosol produced by the Nabro eruption had affected ice clouds. We found no significant modifications of either of ice cloud optical properties (i.e., total backscattering and extinction), occurrence frequencies, or residence altitudes on a global scale. Using the analyzed optical properties as indicators of posteruptive ice cloud radiative forcing modifications, we find that the eruption had no significant volcanic aerosol‐ice cloud radiative effect. Our results suggest that the investigated optical properties of ice and cirrus clouds are at most weakly dependent on the sulfate droplet number density and size distribution.
Response of Unconfined Aquifer to Sudden Change in Boundary Head

Simple, analytical approximations to the solution of the one-dimensional Boussinesq equation are obtained using a weighted residual method. The approach can be applied to both the recharging and the dewatering of an unconfined, homogeneous aquifer from a fully penetrating trench. Estimates for recharge, discharge, and the elevation of the water table are given by explicit algebraic expressions. Comparison with numerical solutions illustrates the accuracy of these new formulas.
MIT Open Access

Consumer products like foods contain numerous polymeric and particulate additives that play critical roles in maintaining their stability, quality and function. The resulting materials exhibit complex bulk and interfacial rheological responses, and often display a distinctive power-law response under standard rheometric deformations. These power-laws are not conveniently described using conventional rheological models, without the introduction of a large number of relaxation modes. We present a constitutive framework utilizing fractional derivatives to model the power-law responses often observed experimentally. We ﬁrst revisit the concept of quasi-properties and their connection to the fractional Maxwell model (FMM). Using Scott-Blair’s original data, we demonstrate the ability of the FMM to capture the power-law response of ’highly anomalous’ materials. We extend the FMM to describe the viscoelastic interfaces formed by bovine serum albumin and solutions of a common food stabilizer, Acacia gum. Fractional calculus allows us to model and compactly describe the measured frequency response of these interfaces in terms of their quasi-properties. Finally, we demonstrate the predictive ability of the FMM to quantitatively capture the behaviour of complex viscoelastic interfaces by combining the measured quasi-properties with the equation of motion for a complex ﬂuid interface to describe the damped inertio-elastic oscillations that are observed experimentally.
Conditional Lower Bounds on the Complexity of Probabilistic Inference

The Inference problem in probabilistic networks (given a stochastic variable V , what is the posterior probability that V = v given evidence e? ) has been proven to be intractable; in fact, has a PP-complete decision variant [17]. The currently most efficient algorithms for this problem are all exponential in the treewidth of the moralised graph of the network. We prove, using a recent result of Marx [18], that these algorithms are in some sense optimal: we prove a lower bound of f(G) tw(G) log tw(G) ) for any algorithm solving arbitrary instances of Inference with graph G, unless the ETH fails. To obtain this lower bound we introduce treewidth-preserving reductions which may be of independent interest.
Annually resolved events of Younger Dryas glaciation in Lochaber (Glen Roy and Glen Spean), western Scottish Highlands

This paper presents the results of micromorphological analysis of laminated sediments that accumulated in ice‐dammed lakes in Lochaber (Glen Roy and vicinity) during the Younger Dryas (Loch Lomond) Stadial. These lakes were responsible for the formation of the famous ‘Parallel Roads of Glen Roy’ (Agassiz, 1840 ), prominent shorelines cut into the valley sides of Glen Roy and adjacent valleys. Annually deposited (varved) layers, which can be distinguished from other rhythmites by micromorphological examination, have enabled the construction of a varve chronology which underpins the glacial history of the region, the duration of the lake stands and rates of ice margin advance and retreat. The lake system existed for a total of 515 a. During a rise in lake levels, the lowermost (260 m), middle (325 m) and highest (350 m) lakes existed for minimal periods of 191, 112 and 116 a, respectively, and the fall of lake levels from 350 m to 260 m took 95 years. Ice advance rates of between 13.4 and 41.9 m a−1 are inferred, while ice retreat is estimated to have been ∼38.5 m a−1. A provisional correlation between the Lochaber varve and GRIP ice core records suggests that the lakes started to form at ca. 12 165 a BP, in turn implying that the Loch Lomond Readvance limits in this area were not achieved until late in the Younger Dryas interval, a conclusion which does not accord with that based on numerical model simulations. Copyright © 2010 John Wiley & Sons, Ltd.
The Shaugh Moor Project: First Report

Viewed from the south Devon littoral with its series of good harbours the dark bulk of Dartmoor is clearly visible across the flat coastal plain. It is the largest of the five granite masses that provide a spine to the south-west English peninsula (Dartmoor, Bodmin Moor, Hensbarrow, Carnmenellis and Penwith) that were formed by the consolidation of molten material. The 500 square kilometres of the Moor form an undulating upland up to 600 m OD on the north-east side, where the greatest elevations occur. In the southern parts of the Moor the rolling tableland is 300 m to 420 m high—modern cultivation tends to cease at the 300 m contour, that is broken by numerous upland valleys and the eroded remains of tors. Today this expanse of moorland is bleak and treeless except in river valleys at the rim of the granite escarpment, although patches of contorted oak woodland survive at Piles' Wood on the River Erme, Wistman's Wood on the West Dart and Black Tor Beare on the West Okement. Pollen analyses have shown, however, that up to a height of about 360 m Dartmoor was probably covered by a deciduous forest dominated by oak that was gradually eroded by climatic trends and human activity (e.g. Simmons, 1969). It is from this central mass that the rivers of south Devon diverge. The wide upland valleys of the Tavy, Plym, Yealm, Erme, Avon and Dart plunge through characteristic deep wooded gorges near the southern granite escarpment into the South Hams and around this border modern settlement—numerous villages and a few towns are situated.
Three‐dimensional simulations of the southern polar giant impact hypothesis for the origin of the Martian dichotomy

We demonstrate via numerical simulations that the impact of a ~lunar‐sized body with Mars is capable of creating a hemispherical magma ocean that upon cooling and solidification resulted in the formation of the southern highlands and thus the Martian dichotomy. The giant impact may have contributed a significant amount of iron to the Martian core and generated a deep thermal anomaly that led to the onset and development of the volcanism in the southern highlands. Our model predicts several mantle plumes converging to the South Pole from the equatorial regions as well as new plumes forming in the equatorial region and also an absence of significant large‐scale volcanism in the northern lowlands. The core heat flux evolution obtained from our numerical models is consistent with the decline of the magnetic field. We argue that such a scenario is more consistent with a range of observations than a northern giant impact (excavating the Borealis basin) for the formation of the Martian dichotomy.