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Previous studies show that the coffee-ring effect can be suppressed by altering the droplet's evaporation rate, surface tension, surface properties, and shape of particles. This experiment used five types of particles with different densities to analyze their behavior during the droplet evaporation process. The results showed that when the particle density is close to the fluid density, the particles move within the droplet and accumulate at the edges, forming a pronounced coffee-ring effect. Conversely, with the higher difference between the particle density and the fluid density increases, they tended to deposit uniformly at the bottom of the droplet and were less likely to be pushed to the edges by capillary effects, effectively suppressing the coffee-ring effect. We also observed that the movement speed of high-density particles relatively slowed down through particle image velocimetry tracking technology. By analyzing the Peclet number and the timescale between particle sinking speed and particle movement speed due to capillary flow, we explained how particle density influences the critical factors of particle sinking and suspension, thereby inhibiting the formation of the coffee-ring effect. [ABSTRACT FROM AUTHOR]

The article focuses on investigating the dynamics of a three-species food chain model with discrete timescales. Topics include the impact of slow, fast, and intermediate timescales on species abundance, the role of homoclinic orbits in inducing chaos, and the significance of ecological modeling in understanding complex ecosystem behaviors.

Recognition of the critical importance of positioning, navigation, and timing to all economic sectors is driving the development of diverse alternatives to global navigation satellite systems (GNSSs), termed AltPNT. One promising approach is to leverage the proliferation of small satellite constellations in low Earth orbit (LEO) to deliver GNSS augmentation services. The generation of one-way ranging signals suitable for AltPNT requires stable timing, accurately referenced to a common timescale such as Global Positioning System Time or Coordinated Universal Time. This paper describes a small-scale laboratory demonstration of an approach for cooperatively realizing a local timescale using low-size, weight, and power clocks distributed across multiple platforms, with no dependence on a GNSS. The demonstration is based on four interconnected software-defined radios to represent a four-satellite subset of a LEO constellation. Lab results show how each platform can generate a common timescale, with stability benefiting from all reference clocks. [ABSTRACT FROM AUTHOR]

In this paper we continue with our investigation of principal and antiprincipal solutions at infinity solutions of a dynamic symplectic system. The paper is a continuation of part I appeared in Differential Equations and Applications in 2022, where we have presenteded a theory of genera of conjoined bases for symplectic dynamic systems on time scales and its connections with principal solutions at infinity and antiprincipal solutions at infinity for these systems together with some basic properties of this new concept on time scales. Here we provide a characterization of all principal solutions of dynamic symplectic system at infinity in the given genus in terms of the initial conditions and a fixed principal solution at infinity from this genus. Further, we provide a characterization of all antiprincipal solutions of dynamic symplectic system at infinity in the given genus in terms of the initial conditions and a fixed principal solution at infinity from this genus. We also establish mutual limit properties of principal and antiprincipal solutions at infinity. [ABSTRACT FROM AUTHOR]

The uncertainty of the climatic effect of Black carbon (BC) remains large. One critical uncertainty source that needs to be captured is BC aging. Here we use the Community Atmosphere Model version 6 (CAM6) configured with the four‐mode version of the Modal Aerosol Module (MAM4) to evaluate the modeled BC aging process with recent laboratory and in‐situ measurements over China. As revealed by the comparison of BC aging timescale and number fraction of aged BC against recent measurements, the modeled condensation aging timescale is estimated to be about 0.8 hr (17%) faster than the chamber measurement, and the diurnal variations of modeled BC aging degree are typically higher than observations mainly due to the fast increase in modeled BC aging degree during daytime. Further analysis shows that the condensation aging dominates (>70%) BC aging across China. More specifically, the condensation of secondary organic aerosol (SOA) vapor contributes most to BC aging over China. Slowing down BC aging increases the modeled surface BC concentration over remote Western China and BC burden, but hardly changes surface BC concentration over Eastern China. Our results suggest that BC aging representation in the MAM4 needs to be further improved toward slowing down the BC aging rate, especially the condensation aging by SOA, to improve the BC simulation over remote areas and its impact on BC transport in MAM4. Plain Language Summary: Black carbon (BC) has a warming effect on climate. Currently, significant divergences in simulated BC burden and optical properties have been shown among global climate models (GCMs), and hence BC radiative forcing remains largely uncertain. BC aging is one of the key processes that contribute to uncertainties in BC simulation. In this study, we evaluate the BC aging process in a global climate model with recent laboratory and in‐situ measurements over China. Our study illustrates that BC aging is too fast in the model compared with observations, and the dominant process for modeled BC aging is SOA vapor condensation over China. We further show how different BC aging rates might affect modeled surface BC concentration and BC burden. Our results suggest that further measurements are needed to better understand BC aging mechanism to improve BC aging in GCMs. Key Points: BC aging is too fast in MAM4 compared against measured BC condensation aging timescale and number fraction of aged BCSOA vapor condensation plays a dominant role in modeled BC aging process over ChinaSlowing down BC aging increases surface BC over remote Western China and BC burden, but hardly changes surface BC over Eastern China [ABSTRACT FROM AUTHOR]

Building on recent work identifying how the infrastructures of human social and economic life themselves depend on the "natural infrastructure" of biogeochemical systems, I explore the idea that infrastructuring - involving causal relations between subsystems operating at different timescales - might be a strategy widely adopted by matter undergoing self-organization under planetary conditions. I analyze the concept of infrastructure as it is used to describe features of the human "technosphere" and identify the importance of a difference in timescales between supporting and supported structures and processes. I explore some examples of how the wider planet might be said to engage in timescale-distancing and infrastructuring, focusing in particular on examples from the hydrosphere and biosphere. I then turn to the question of how to explain infrastructuring, developing a neocybernetic account of infrastructuring as involving the separation of a system into subsystems at different timescales in mutual but asymmetrical causal relations. I conclude by exploring the implications of this approach for the way we think about planets in general and the human technosphere. [ABSTRACT FROM AUTHOR]

We study the influence of a cosmological population of dense gas clouds on distant sources, with an emphasis on quasar optical variability. In addition to gravitational lensing, such clouds affect flux measurements via refraction in the neutral gas and via dust extinction, leading to a variety of possible light curves even in the low optical depth limit. We classify and illustrate the types of light curves that can arise. For sources as large as quasars, we show that gravitational lensing and extinction are the dominant effects, with gas refraction playing only a minor role. We find that clouds with mass |$\sim 10^{-4.5\pm 0.5}\, \mathrm{M}_\odot$| can reproduce the observed distribution of quasar variation amplitudes, but only if such clouds make up a large fraction of the closure density. In that case, there may also be substantial extinction of distant optical sources, which can, in principle, be constrained by data on 'standard candles' such as type Ia supernovae. Unfortunately, that extinction is essentially grey, even when the material opacity is strongly wavelength dependent, making it difficult to distinguish from the influence of the background geometry. We propose a novel statistical test of the origin of quasar variability, based on the angular structure of the variation timescale for a large number of quasars distributed all over the sky. If quasar variability is primarily due to nanolensing, then angular structure is expected to include a quadrupole term of amplitude |$\sim 5{{\ \rm per\ cent}}$|⁠ , which ought to be measurable with future data from the Gaia mission. [ABSTRACT FROM AUTHOR]

A coastal sea level reconstruction based on tide gauge observations is developed and applied to the western basin of the Mediterranean sea. The reconstructions are carried out in four frequency bands and are based on an optimal interpolation method in which the correlation between tide gauge data and all coastal points has been determined from the outputs of a numerical model. The reconstructions for frequencies lower than 1 month use monthly observations from the PSMSL database and cover the period from 1884 to 2019. For the reconstruction of higher frequencies, hourly observations from the GESLA-2 dataset are used, and cover from 1980 to 2015. Total sea level is retrieved with high accuracy from the merging of the different frequency bands. Results of a cross-validation test show that independent tide gauge series are highly correlated with the reconstructions. Moreover, they correlate significantly better with the reconstructions than with altimetry data in all frequency bands, and therefore the reconstruction represents a valuable contribution to the attempts of recovering coastal sea level. The obtained reconstructions allow the characterization of the coastal sea level variability, to estimate coastal sea level trends and to examine the correlation between Western Mediterranean coastal sea level and the main North Atlantic climate indices. The limitations and applicability of the method to other regions are also discussed. [ABSTRACT FROM AUTHOR]

The epistemological challenges of the Anthropocene trouble distinctions of solid and fluid. In this contribution, the author proposes, after Gabrielle Hecht, that the nuclearity of the Anthropocene contributes significantly to destabilising these categories. Nuclear materials and ideas of nuclearity force (re)consideration of deep timescales and imperceptible processes, problematising fixed material ontologies. The article engages with nuclear matters and queries the logic of solids and fluids by developing the notion of elemental memory. An attention to elemental memory – an element's capacity to auto-affect over time – reveals the inadequacy of terms like solid and fluid, and highlights the expressiveness of solid fluid substances. Empirically, the author demonstrates, first, how elemental memory informs the solid-fluid processuality of radioactive glasses, especially trinitite. Second, engaging with the work of artists Mari Keto and Erich Berger, she addresses the slow auto-transformations of radioactive minerals. [ABSTRACT FROM AUTHOR]

The factors driving variability in rainfall stable water isotopes (specifically δ18O and deuterium excess, d = δ2H − 8 δ18O) were studied in a 13‐year data set of daily rainfall samples from coastal southwestern Western Australia (SWWA). Backwards dispersion modeling, automatic synoptic type classification, and a statistical model were used to establish causes of variability on a daily scale; and predictions from the model were aggregated to longer temporal scales to discover the cause of variability on multiple timescales. Factors differ between δ18O and d and differ according to temporal scale. Rainfall intensity, both at the observation site and upwind, was most important for determining δ18O and this relationship was robust across all time scales (daily, seasonal, and interannual) as well as generalizing to a second observation site. The sensitivity of δ18O to rainfall intensity makes annual mean values particularly sensitive to the year's largest events. Projecting the rainfall intensity relationship back through ∼100 years of precipitation observations can explain ∼0.2 $0.2$–0.4‰ shifts in rainfall δ18O. Twentieth century speleothem records from the region exhibit signals of a similar magnitude, indicating that rainfall intensity should be taken into account during the interpretation of regional climate archives. For d, humidity during evaporation from the ocean was the most important driver of variability at the daily scale, as well as explaining the seasonal cycle, but source humidity failed to explain the longer‐term interannual variability. Plain Language Summary: In cave deposits, as with several other natural systems, the relative abundance of the heavy isotopes oxygen‐18 and deuterium can be used to determine past changes in climate. This is because the isotopic composition of these systems is linked to that of rainfall, while the abundance of heavy isotopes in rainfall is driven by climate parameters such as temperature and rainfall characteristics. For this to be possible, the factors which drive rainfall isotopic variability need to be well known. This study uses a 13‐year data set of daily rainfall samples from coastal southwestern Western Australia to better understand isotopic variability for this region. Oxygen‐18 variations here are driven mainly by rainfall intensity (the amount of rain each day) both according to measurements at the site and upwind simulations. Deuterium excess, a second order parameter which is often linked to conditions in the evaporation source region, was well‐predicted by source region humidity at the daily scale but not when aggregated to annual totals. The relationship between rainfall intensity and oxygen‐18 appears to be important over the 20th century, based on a comparison between observed rainfall and a cave record. Key Points: Precipitation δ18O variability is driven primarily by rainfall intensity in southwestern Western AustraliaInterannual δ18O variability is strongly influenced by the largest rainfall events of the yearHumidity during evaporation drives deuterium excess variability at a daily, but not interannual, timescale [ABSTRACT FROM AUTHOR]

Liquid atomization determines the initial conditions for flame formation and particle synthesis. Without a stable flame, high droplet velocities and thus short droplet residence time in the flame may lead to droplets being injected into an extinguished flame, which influences synthesis and final particle output. An experimental investigation of spray formation and flame stability is performed through high-speed visualization. Targeted variation of nozzle geometry is applied to improve spray-flame interaction and compared to a standardized burner. Timescales of spray density and flame fluctuations are quantified and compared, where the latter were significantly larger and hence not correlated. Instead, dispersion gas forms a barrier between spray phase and pilot flame; hence, ignition depends on large liquid lumps with high radial momentum to break through the dispersion gas for spray ignition. Angling of dispersion gas flow increases radial shear and turbulence and leads to refined atomization and improved flame stability. To investigate the nozzle influence on particle formation, particle characteristics are examined by online and offline analytics with focus on particle structures and product purity. The modified nozzle produced smaller primary particle sizes, thus indicating a sensitivity of sintering dominance on the nozzle geometry. Impurities impact the examination of particle structures and general particle functionality. Carbon contamination was apparent in synthesized particles and also indicated sensitivity to nozzle geometry. Discrepancies to literature data are discussed regarding differences in flame activity and droplet characteristics. The report highlights, how product characteristics can differ crucially due to changes in nozzle geometry despite comparable operating conditions. [ABSTRACT FROM AUTHOR]

The human cortex exhibits intrinsic neural timescales that shape a temporal hierarchy. Whether this temporal hierarchy follows the spatial hierarchy of its topography, namely the core-periphery organization, remains an open issue. Using magnetoencephalography data, we investigate intrinsic neural timescales during rest and task states; we measure the autocorrelation window in short (ACW-50) and, introducing a novel variant, long (ACW-0) windows. We demonstrate longer ACW-50 and ACW-0 in networks located at the core compared to those at the periphery with rest and task states showing a high ACW correlation. Calculating rest-task differences, i.e., subtracting the shared core-periphery organization, reveals task-specific ACW changes in distinct networks. Finally, employing kernel density estimation, machine learning, and simulation, we demonstrate that ACW-0 exhibits better prediction in classifying a region's time window as core or periphery. Overall, our findings provide fundamental insight into how the human cortex's temporal hierarchy converges with its spatial core-periphery hierarchy. Golesorkhi et al. use a combination of magnetoencephalography data, machine learning and simulation to investigate intrinsic neural timescales during resting and task states. They provide insight into how the temporal hierarchy of the human cortex converges with its spatial core-periphery hierarchy. [ABSTRACT FROM AUTHOR]

Suspended colloidal particles assemble into "bands" when subject to shear flow and a DC electric field over a range of conditions in combined Poiseuille and electroosmotic counterflow through microchannels. The initial stage in this process appears to be an accumulation stage, where particles are attracted to and concentrated near the channel wall. Spatially averaged grayscales and their standard deviation were calculated from evanescent-wave visualization images of band assembly to estimate the near-wall particle concentration and its local variations, respectively. The timescale for the accumulation stage was estimated from the standard deviation and used to scale physical time. The average grayscale appears to grow exponentially during the accumulation stage and exhibits self-similar exponential growth when normalized by its maximum value over a range of experimental parameters. [ABSTRACT FROM AUTHOR]

Time-resolved serial femtosecond crystallography (TR-SFX) at an x-ray free electron laser enables protein structural changes to be imaged on time-scales from femtoseconds to seconds. It can, however, be difficult to grasp the nature and timescale of global protein motions when structural changes are not isolated near a single active site. New tools are, therefore, needed to represent the global nature of electron density changes and their correlation with modeled protein structural changes. Here, we use TR-SFX data from bacteriorhodopsin to develop and validate a method for quantifying time-dependent electron density changes and correlating them throughout the protein. We define a spherical volume of difference electron density about selected atoms, average separately the positive and negative electron difference densities within each volume, and walk this spherical volume through all atoms within the protein. By correlating the resulting difference electron density amplitudes with time, our approach facilitates an initial assessment of the number and timescale of structural intermediates and highlights quake-like motions on the sub-picosecond timescale. This tool also allows structural models to be compared with experimental data using theoretical difference electron density changes calculated from refined resting and photo-activated structures. [ABSTRACT FROM AUTHOR]

The authors present insights on their study wherein they directly observed timescales of morphological change for aluminum nanoparticles and aluminum copper oxide (Al-CuO) nanocomposite thermite using dynamic transmission electron microscopy. Topics discussed include the use of coalescing and sintering into much larger particles, the thin spots in the oxide shell between two metal cores, and the ejection of some particles from the agglomerate during the occurrence of dispersion.

Rockfalls commonly exhibit power law volume‐frequency distributions, where fewer large events are observed relative to more numerous small events. Within most inventories, the smallest rockfalls are the most difficult to detect and so may not be adequately represented. A primary challenge occurs when neighboring events within a single monitoring interval are recorded as one, producing ambiguity in event location, timing, volume, and frequency. Identifying measurement intervals that minimize these uncertainties is therefore essential. To address this, we use an hourly data set comprising 8,987 3‐D point clouds of a cliff that experiences frequent rockfalls. Multiple rockfall inventories are derived from this data set using change detections for the same 10‐month period, but over different monitoring intervals. The power law describing the probability distribution of rockfall volumes is highly sensitive to monitoring interval. The exponent, β, is stable for intervals >12 hr but increases nonlinearly over progressively short timescales. This change is manifested as an increase in observed rockfall numbers, from 1.4 × 103 (30 day intervals) to 1.4 × 104 (1 hr intervals), and a threefold reduction in mean rockfall volume. When the monitoring interval exceeds 4 hr, the geometry of detected rockfalls becomes increasingly similar to that of blocks defined by rock mass structure. This behavior change reveals a time‐dependent component to rockfall occurrence, where smaller rockfalls (identifiable from more frequent monitoring) are more sensitive to progressive deformation of the rock mass. Acquiring complete inventories and attributing discrete controls over rockfall occurrence may therefore only be achievable with high‐frequency monitoring, dependent upon local lithology. Plain Language Summary: Rockfall inventories are required to model erosion, such as along coastlines or in mountain landscapes, and hazard from rockfall activity. The frequency distribution of rockfall volumes, commonly termed "magnitude‐frequency", is important for this modeling and for our understanding of how rockfalls occur and what drives them. For rockfalls and landslides in general, these distributions typically follow a power law, with relatively few larger rockfalls as compared to more numerous small events. Advances in hardware and algorithms have considerably improved the spatial resolution and precision with which a given rock face can be monitored using LiDAR. This has in turn improved our ability to detect small rockfalls, which in sum contribute significantly to overall volume loss from rock slopes in this setting. The improvement in spatial resolution has, however, considerably outpaced improvements in the temporal resolution of monitoring. If the interval between surveys is greater than the return interval of rockfalls, neighboring rockfalls within a single monitoring interval are recorded as one, producing ambiguity in event, timing, and volume. For the latter, this effect may amount to an order of magnitude variation. Our research aimed to examine the timescales over which rockfalls occur, allowing us to identify suitable monitoring intervals to discretize rockfalls. While conventional monitoring campaigns tend to acquire surveys at monthly intervals or longer, we draw upon a 1 hr resolution data set acquired over 10 months. We find that the interval of monitoring has a considerable impact on the probability distribution of measured rockfall volumes. An order of magnitude increase in rockfall numbers and a threefold decrease in mean rockfall volume are observed over timescales (monitoring intervals) of 1 hr, rather than 30 days. This is represented by a change in the power law exponent of the magnitude‐frequency relationship, which increases nonlinearly below timescales of ~12 hr. Interestingly, above ~12 hr, the exponent is stable, suggesting that changes in monitoring interval above this timescale will attain almost identical rockfall inventories. We explain this change in behavior by relating the geometry of rockfalls to the geometry of the blocks from which they are released. The average size of rockfalls identified over timescales below ~4 hr is comparable to the scale of individual discontinuities, indicating that fragmented detachments are more likely to control the increase in small events. As the timescale of rockfall monitoring increases, detachments become more similar to the rock mass structure, indicating structural control on failure. This behavior change suggests that smaller rockfalls are more sensitive to progressive deformation of the rock mass. This type of analysis is required to constrain the timescales over which this process occurs, which is necessary to understand prior to attributing specific drivers (such as storms) to rockfall occurrence. Key Points: The magnitude‐frequency distribution of rockfall inventories is highly sensitive to the time interval between monitoring surveysMonitoring intervals below ~12 hr yield a nonlinear increase in the number of rockfalls observed and a decrease in mean rockfall volumeAt monitoring intervals above ~12 hr, the distribution is stable and rockfall geometry converges with that defined by rock mass structure [ABSTRACT FROM AUTHOR]

This study explores regrading in interaction, with a specific focus on regrading involving timescales. There are at least two ways of upgrading and downgrading with timescales. A detailed analysis of conversations in Japanese between friends examines two types of timescale: linear (timescales in which something can change as time progresses; e.g., deterioration over time) and cyclical (repeating timescales; e.g., years, days of the week). In these interactions, upgrading occurs when a speaker has succeeded in establishing tellability of a second story by eliciting expected responses from a recipient. These upgrades may then be followed by downgrades when they are vulnerable to being challenged. In addition to contributing to an understanding of interactional regrading, scaling, and timescales in general, this study demonstrates the complex interaction among scales and speakers' manipulation of multiple scales. • Two types of timescales are examined. • Two ways of doing regrading involving timescales are revealed. • The complex interaction among scales are reported. • Speakers' manipulation of multiple scales are described. [ABSTRACT FROM AUTHOR]

Mooring data from September 2011 to July 2013 on the Iceland slope north of Denmark Strait are analyzed to better understand the structure and variability of the North Icelandic Jet (NIJ). Three basic configurations of the flow were identified: (1) a strong separated East Greenland Current (EGC) on the mid‐Iceland slope coincident with a weak NIJ on the upper slope, (2) a merged separated EGC and NIJ, and (3) a strong NIJ located at its climatological mean position, coincident with a weak signature of the separated EGC at the base of the Iceland slope. Our study reveals that the NIJ‐dominant scenario was present during different times of the year for the two successive mooring deployments—appearing mainly from September to February the first year and from January to July the second year. Furthermore, when this scenario was active it varied on short timescales. An energetics analysis demonstrates that the high‐frequency variability is driven by mean‐to‐eddy baroclinic conversion at the shoreward edge of the NIJ, consistent with previous modeling work. The seasonal timing of the NIJ dominant scenario is investigated in relation to the atmospheric forcing upstream of Denmark Strait. The resulting lagged correlations imply that strong turbulent heat fluxes in a localized region on the continental slope of Iceland, south of the Spar Fracture zone, lead to a stronger NIJ dominant state with a two‐month lag. This can be explained dynamically in terms of previous modeling work addressing the circulation response to dense water formation near an island. Plain Language Summary: The dense water flowing southward through Denmark Strait represents the largest contribution to the deep limb of the Atlantic Meridional Overturning Circulation, the large‐scale flow pattern that helps regulate Earth's climate. Three different currents feed the overflow in the strait: the shelfbreak East Greenland Current adjacent to Greenland, the separated East Greenland Current located farther offshore, and the North Icelandic Jet (NIJ) on the Iceland continental slope. The latter, which was recently discovered, supplies the deepest and densest overflow water to the strait. To understand the structure and variability of the NIJ, we analyze two years of mooring data on the Iceland slope roughly 200 km northeast of Denmark strait. We present the spatial and temporal variability of three configurations of the flow and focus on the NIJ‐dominant scenario. The rapid (less than 1 week) variability is found to arise from instability associated with the current's density structure. We then address the monthly variation, which we argue is driven by air‐sea heat fluxes in a localized region on the continental slope north of Iceland. The ocean responds to the fluxes in this region by exciting waves that propagate clockwise around the island, which in turn impact the strength of the NIJ. Key Points: Three different configurations of the flow on the Iceland slope north of Denmark Strait are identified using two years of mooring dataThe configuration where the North Icelandic Jet (NIJ) is dominant is baroclinically unstable and occurs during different times during the two yearsWe seek to explain the seasonal timing when the NIJ is dominant on Iceland slope to upstream atmospheric forcing [ABSTRACT FROM AUTHOR]

Explaining why fluctuations in abundances of spatially disjunct populations often are correlated through time is a major goal of population ecologists. We address two hypotheses receiving little to no testing in wild populations: (i) that population cycling facilitates synchronization given weak coupling among populations, and (ii) that the ability of periodic external forces to synchronize oscillating populations is a function of the mismatch in timescales (detuning) between the force and the population. Here, we apply new analytical methods to field survey data on gypsy moth outbreaks. We report that at timescales associated with gypsy moth outbreaks, spatial synchrony increased with population periodicity via phase locking. The extent to which synchrony in temperature and precipitation influenced population synchrony was associated with the degree of mismatch in dominant timescales of oscillation. Our study provides new empirical methods and rare empirical evidence that population cycling and low detuning can promote population spatial synchrony. [ABSTRACT FROM AUTHOR]

The traditional electromagnetic transient (EMT) model of transmission line is very slow for the large-scale power systems simulation due to the small step. To accelerate the electro-magnetic transient program (EMTP) calculation, a modified line model used for realising multi-step simulation is proposed. This model is based on the timescale transformation of single-phase coordinate which can transform the primary high-frequency signal into a lower one. By this means, the part which needs to be simulated in detail, such as power electronic devices, can be calculated with a small time step, and a large time step can be used for the other part. In this article, the basic theory of timescale transformation is introduced firstly, and then the new line model is deduced in detail. Finally, a simple system is simulated by the new and traditional model, respectively, and the validity of this approach is verified by comparing with the traditional EMTP simulation. Furthermore, due to the large-step simulation, the calculation speed is improved. [ABSTRACT FROM AUTHOR]

The mobilities of increasing numbers of 'middling' migrants from Asia to Australia involve complex trajectories that encompass multiple transitions across statuses and places as well as ambiguities around temporariness and permanence. This article argues that during these 'staggered' migrations, intersections between multiple 'timescales' – institutional, biographic and everyday – produce specific experiences of time for migrants that interrupt teleological imaginaries of both life transitions and migration outcomes. Drawing on data from in-depth narrative interviews with middling migrants, this article focuses on two such temporal experiences, 'contingent temporality' and 'indentured temporality', and seeks to demonstrate how these experiences are produced through the overlaps and intersections of institutional, biographical and everyday timescales. The article seeks to advance empirical understandings of the temporalities of new forms of migrant mobility between Asia and Australia, as well as to contribute new conceptual approaches to scholarship on migration and time. [ABSTRACT FROM AUTHOR]

Abstract This paper explores persistence of eight largest cryptocurrency markets using daily data from 25 ∕ 08 ∕ 2015 – 13 ∕ 03 ∕ 2018 , across time and trading scale. Employing ARFIMA-FIGARCH class of models under two different distributions and a modified log-periodogram method, we generally uncovered informational (in)efficiency and volatility persistence to be highly sensitive to time-scale, the measure of returns and volatilities, and regime shift. In particular, evidence of persistence was found to be concealed in full-sample conditional returns and a break regime, where three crypto markets showed characteristics contrary to the Efficient Market Hypothesis. These results suggest that empirical examination of persistence in markets should be mindful of volatility measures, trading horizons, and switching regimes. More so, scale-conscious traders or investors could rely on our findings and the implications thereof in making investment decisions in the market. Highlights • Long-memory and informational (in)efficiency of major cryptocurrencies are examined. • Three markets showed informational inefficiency for the aggregate return series. • Efficiency and volatility persistence are dependent on scale and data variations. • Manipulative trend trading excessive gains are less likely in the long-run scale. [ABSTRACT FROM AUTHOR]

Hosting the Rugby World Cup in 2011 offered a chance for New Zealand to showcase itself on the world stage, but also provided immigrants to the country an opening to assert their legitimate place in the nation. We present the particular case of Leslie, a Filipina migrant, and her Facebook activities during the tournament. Approaching these texts through the frameworks of liminality and timescale-differentiated identity construction along with Social Actor Network Analysis, we unravel the discourses of national belonging facilitated by the interaction of social media and a sporting mega-event. Our analysis shows that Facebook's semiotic affordances, interconnectivity and ability to bridge time and distance allowed Leslie to be part of the collective by performing an emerging identity as a New Zealander. As a result, she transcended the identity of being an other in New Zealand to – at least for this period – take on one of national belonging. [ABSTRACT FROM AUTHOR]

Abstract Integrating large amounts of variable generation (VG) resources such as wind and solar into a region's power grid without causing significant VG curtailment will likely require increased system flexibility via changing grid operation and deploying enabling technologies such as energy storage. This article analyzes the storage duration required to reduce VG curtailment under high-VG scenarios. The three analysis scenarios assume VG provides 55% of the electricity demand in the largely isolated Electricity Reliability Council of Texas grid system in 2050, with three different proportions of wind and solar generation. Across the three scenarios, 11%–16% of VG energy is curtailed without storage due to system-generation constraints. When 8.5 GW of storage capacity with 4 h of duration are added, curtailment is reduced to 8%–10% of VG. Additional storage duration further reduces curtailment, but with rapidly diminishing returns. At least half the potential avoided-curtailment benefits are realized with 8 h of storage, and the first 4 h provide the largest benefit. At VG penetrations up to 55%, there appears to be little incremental benefit in deploying very-long-duration or seasonal storage. Highlights • Variable generation (VG) curtailment can be avoided using energy storage. • Scenarios of 55% VG penetration are evaluated with different mixes of wind and solar. • At 55% VG, at least half the avoided-curtailment benefits are met with 8 h of storage. • At 55% VG there is little incremental benefit of very-long-duration or seasonal storage. [ABSTRACT FROM AUTHOR]

The Triassic rocks are widespread in China, and both marine and terrestrial strata are well developed. The Triassic stratigraphic architecture of China is very complex in both spatial variation of the so-called "South Marine and North Continental", i.e. the southern areas of China occupied mostly by marine facies while the northern China by terrestrial facies during the Triassic Period, and temporal transition of the "Lower Marine and Upper Continental", i.e. the lower part of the Triassic System composed mainly of marine facies and the upper part of terrestrial strata especially in South China. Although the Global Stratotype Section and Point (GSSP) of the Permian-Triassic boundary is located in South China, the Triassic of China except for some marine Lower-Middle Triassic depositions shows significantly local characteristics and is hardly correlated with the global chronostratigraphic chart. Consequently, the Triassic of China contains not only the international research hotspots but also difficult points in stratigraphic study. This paper aims to present a brief review of the Triassic in China, including chronostratigraphy, biostratigraphy, magnetostratigraphy and chemostratigraphy, and summarize an integrated Triassic stratigraphic framework of China. Accordingly, a stratigraphic correlation is proposed for the lithostratigraphic sequences among the three tectono-paleogeographic stratigraphic regions. The comprehensive study indicates that ammonoids are the classic index fossils in Triassic biostratigraphy but conodonts are more advantageous in the study and definition of the Triassic chronostratigraphic boundaries. China still has the potential to optimize the GSSPs of the Induan-Olenekian boundary and Olenekian-Anisian boundary. The correlation of the Permian-Triassic boundary between marine and terrestrial facies might be achieved with the help of the Permian-Triassic "transitional bed" and its related biotic and environmental events in association with the biostratigraphic study of conchostracan, vertebrate and plant fossils. In addition, the carbon isotopes have been proved to be one of the powerful methods in marine Triassic stratigraphic study, whereas the oxygen and strontium isotopes may be additional important bridges to establish the correlation between the marine and terrestrial strata, but as yet lacking of relevant studies in terrestrial strata. Considering the most stratigraphic intervals of the Triassic and the terrestrial Triassic in China are difficult to be correlated to the global chart, the proposed Chinese (regional) Triassic chronostratigraphic chart of marine and terrestrial stages would be of importance to the study of Chinese Triassic stratigraphy and related aspects, but the stages must be conceptually in line with international standards and studied as soon as possible in order to finalize the definition. [ABSTRACT FROM AUTHOR]

The Cambrian Period is the first period of the Phanerozoic Eon and witnessed the explosive appearance of the metazoans, representing the beginning of the modern earth-life system characterized by animals in contrary to the Precambrian earth-life system dominated by microbial life. However, understanding Cambrian earth-life system evolution is hampered by regional and global stratigraphic correlations due to an incomplete chronostratigraphy and consequent absence of a highresolution timescale. Here we briefly review the historical narrative of the present international chronostratigraphic framework of the Cambrian System and summarize recent advances and problems of the undefined Cambrian stage GSSPs, in particular we challenge the global correlation of the GSSP for the Cambrian base, in addition to Cambrian chemostratigraphy and geochronology. Based on the recent advances of the international Cambrian chronostratigraphy, revisions to the Cambrian chronostratigraphy of China, which are largely based on the stratigraphic record of South China, are suggested, and the Xiaotanian Stage is newly proposed for the Cambrian Stage 2 of China. We further summarize the integrative stratigraphy of South China, North China and Tarim platforms respectively with an emphasis on the facies variations of the Precambrian-Cambrian boundary successions and problems for identification of the Cambrian base in the different facies and areas of China. Moreover, we discuss stratigraphic complications that are introduced by poorly fossiliferous dolomite successions in the upper Cambrian System which are widespread in South China, North China and Tarim platforms. [ABSTRACT FROM AUTHOR]

The Paleogene is the first period after the Mesozoic Mass Extinction. Mammals become the dominant group in the terrestrial ecosystem with a rapid radiation, and Asia has been considered to be the origin place of several mammalian groups. The Paleogene System consists mostly of terrestrial deposits in Asia, especially in East Asia. A well-established regional chronostratigraphic framework is the foundation for understanding both the Paleogene geologic history and evolutionary history of Asia and their relationships. The Paleogene is subdivided into the Paleocene, Eocene and Oligocene in the International Chronostratigraphic Chart. Based on the land mammal ages, the Chinese terrestrial Paleogene can be subdivided into 11 stages: the Shanghuan, Nongshanian and Bayanulanian stages of the Paleocene, the Lingchan, Arshantan, Irdinmanhan, Sharamurunian, Ulangochuian and Baiyinian stages of the Eocene, and the Ulantatalian and Tabenbulukian stages of the Oligocene. These stages have distinctive paleontological characters, with special significance of fossil mammals, which provide a reliable practical basis. The bases of the Shanghuan, Lingchan, and Ulantatalian stages are coincident respectively with those of the Paleocene, Eocene and Oligocene. The ages for their bases are determined as 66.0, 56.0 and 33.9 Ma, respectively, following that for the corresponding series in the International Chronostratigraphic Chart. For other stages, estimated ages are provided based on available paleomagnetic results. [ABSTRACT FROM AUTHOR]

The Global Boundary Stratotype Sections and Points (GSSPs) for the bases of all seven international Devonian stages have been formally defined and ratified by IUGS till 1996, and nowadays, the main tasks for Devonian stratigraphers include further subdivision of these standard stages, strictly constrained absolute ages for the boundaries, and precise neritic-pelagic and marine-terrestrial correlations using multidisciplinary stratigraphy methods. Establishment of high-resolution Devonian integrative stratigraphy framework and timescale of China would play an important role in improving regional and international correlation, facilitating the recognition of important stratigraphic levels in different paleogeographic settings, and understanding the evolution pattern of biota, paleoclimate and paleoenvironment during this critical interval. Based on well-studied bio- and chronostratigraphy of Devonian in South China and adjacent areas, in combination with recent achievements in carbon isotope stratigraphy, event stratigraphy and radioactive isotope ages, this paper briefly summarize the research history and current status of Devonian chronostratigraphy of China, and for the first time introduce Devonian integrative stratigraphy framework of China. Up to date, few studies have been conducted on the astronomical cyclostratigraphy and high-resolution radioactive isotope dating in Devonian of China, which should be our main focuses in the near future. [ABSTRACT FROM AUTHOR]

A series of major geological and biological events which altered the evolutionary processes of whole biosphere occurred during the earth history. Establishing a high-resolution stratigraphic framework and timescale is essential to understand their tempo and causes. High-resolution biostratigraphy remains the most useful approach and forms the basis of dividing the chronostratigraphic system and making the inter-continental and regional correlation. China possesses nearly complete strata from Ediacaran to Quaternary covering wide palaeogeographic regions and containing abundant well-preserved fossils. Traditional biostratigraphy based on sytematic palaeontology of various fossil groups have played an important role in establishing the GSSPs and improving the International and Chinese Stratigraphic Charts. 11 out of 72 establised GSSPs are located in China. Recently, more high-precision geochronology, chemostratigraphy, cyclostrtatigraphy have been applied for stratigraphy and correlation and important advances have been made in some periods. This volume invited Chinese palaeontologists and stratigraphers to summarize the progresses of stratigraphy and timescale from Ediacaran to Quaternary and intercontinental and regional correlation during the last two decades. [ABSTRACT FROM AUTHOR]

The Jurassic stratigraphy in China is dominated by continental sediments. Marine facies and marine-terrigenous facies sediment have developed locally in the Qinghai-Tibet area, southern South China, and northeast China. The division of terrestrial Jurassic strata has been argued, and the conclusions of biostratigraphy and isotope chronology have been inconsistent. During the Jurassic period, the North China Plate, South China Plate, and Tarim Plate were spliced and formed the prototype of ancient China. The Yanshan Movement has had a profound influence on the eastern and northern regions of China and has formed an important regional unconformity. The Triassic-Jurassic boundary (201.3 Ma) is located roughly between the Haojiagou Formation and the Badaowan Formation in the Junggar Basin, and between the Xujiahe Formation and the Ziliujing Formation in the Sichuan Basin. The early Early Jurassic sediments generally were lacking in the eastern and central regions north of the ancient Dabie Mountains, suggesting that a clear uplift occurred in the eastern part of China during the Late Triassic period when it formed vast mountains and plateaus. A series of molasse-volcanic rock-coal strata developed in the northern margin of North China Craton in the Early Jurassic and are found in the Xingshikou Formation, Nandailing Formation, and Yaopo Formation in the West Beijing Basin. The geological age and markers of the boundary between the Yongfeng Stage and Liuhuanggou Stage are unclear. About 170 Ma ago, the Yanshan Movement began to affect China. The structural system of China changed from the near east-west Tethys or the Ancient Asia Ocean tectonic domain to the north-north-east Pacific tectonic domain since 170-135 Ma. A set of syngenetic conglomerate at the bottom of the Haifanggou or Longmen Fms. represented another set of molasse-volcanic rock-coal strata formed in the Yanliao region during the Middle Jurassic Yanshan Movement (Curtain A1). The bottom of the conglomerate is approximately equivalent to the boundary of the Shihezi Stage and Liuhuanggou Stage. The bottom of the Manas Stage creates a regional unconformity in northern China (about 161 Ma, Volcanic Curtain of the Yanshan Movement, Curtain A2). The Jurassic Yanshan Movement is likely related to the southward subduction of the Siberian Plate to the closure of the Mongolia-Okhotsk Ocean. A large-scale volcanic activity occurred in the Tiaojishan period around 161-153 Ma. Note that 153 Ma is the age of the bottom Tuchengzi Formation, and the bottom boundary of the Fifth Stage of the Jurassic terrestrial stage in China should have occurred earlier than this. This activity was marked by a warming event at the top of the Toutunhe Formation, and the change in the biological assembly is estimated to be 155 Ma. The terrestrial Jurassic-Cretaceous boundary (ca. 145.0 Ma) in the Yanliao region should be located in the upper part of Member 1 of the Tuchengzi Formation, the Ordos Basin in the upper part of the Anding Formation, the Junggar Basin in the upper part of the Qigu Formation, and the Sichuan Basin in the upper part of the Suining Formation The general characteristics of terrestrial Jurassic of China changed from the warm and humid coal-forming environment of the Early-Middle Jurassic to the hot, dry, red layers in the Late Jurassic. With the origin and development of the Coniopteris-Phoenicopsis flora, the Yanliao biota was developed and spread widely in the area north of the ancient Kunlun Mountains, ancient Qinling Mountains, and ancient Dabie Mountain ranges in the Middle Jurassic, and reached its great prosperity in the Early Late Jurassic and gradually declined and disappeared and moved southward with the arrival of a dry and hot climate. [ABSTRACT FROM AUTHOR]

Silurian is a period with the shortest duration in Phanerozoic except for the Neogene and Quaternary. It represents an important and unique interval when the biotic diversity recovered quickly after the end-Ordovician mass extinction, different paleoplates or terranes conjoined, big oceans disappeared or narrowed, climate and sea level changed frequently, global biotic provincialism became weaker, some primitive plants started to occupy the land. Silurian is also the first system of which all the chronostratigraphic stratotypes (i.e. the GSSPs) including four series and seven stages were established by the International Subcommission on Silurian Stratigraphy (ISSS). Nonetheless, during the post-GSSP studies conducted by ISSS in the middle 1980s, some Silurian GSSPs were found to have some congenital defects such as no index fossils available that hinder the high resolution subdivision and correlation on a regional or global scale. In this paper, based on the latest development of Silurian study in China, the progress in biostratigraphy, chronostratigraphy, event stratigraphy (such as facies differentiation, heterochrony of black shales, marine red beds, carbonate rocks and reefs), chemostratigraphy, and tectonic stratigraphy (e.g., widespread of the late Silurian rocks in South China and its tectonic implication) are systematically summarized. Some existing problems and the areas to be focused in future work are also discussed. It is suitable for chronostratigraphic study to concentrate not only on the boundary but also doing multidisciplinary analysis on the biotic, chemical, magnetic, environmental, and chronologic aspects, in order to enhance the reliability and the potential for regional and global correlation of a certain GSSP. Some important achievements are expected in these areas in the Silurian study in China: (1) ecostratigraphy and basin analysis of the Llandovery, and the correlation of integrative stratigraphy with a high resolution; (2) establishment of the Wenlock to Pridoli chronostratigraphic framework; (3) the chemo- and magnetic stratigraphy and the age of some key intervals and horizons; (4) further investigation on paleogeography and plate tectonics; and (5) origin and early evolution of the terrestrial ecosystem. Some new breakthroughs might occur in the restudy on some of those problematic GSSPs of some particular series and stages. [ABSTRACT FROM AUTHOR]

In this chapter, starting with a brief review of the research history and current status in the studies of the Ordovician chronostratigraphy in China, the subdivision of the Ordovician System, definition and recognition of its series and stage boundaries, and possible stratigraphic gaps are discussed in details in order to establish a multidisciplinary stratigraphic correlation through an integrated approach including lithostratigraphy, biostratigraphy, radiometric dating, chemostratigraphy and magnetostratigraphy. Being internationally accepted, the Ordovician System is now subdivided into three series and seven stages, in ascending order, Lower (Tremadocian, Floian), Middle (Dapingian, Darriwilian) and Upper series (Sandbian, Katian, Hirnantian). Three of the seven "Golden Spikes" defining the bases of the Ordovician stages, which were established in 1997-2007, are located in China. As a regionally applied chronostratigraphy, the Ordovician System was subdivided in China into Lower (Xinchangian, Yiyangian), Middle (Dapingian, Darriwilian) and Upper series (Neichiashanian, Chientangkiangian, Hirnantian). This scheme agrees largely with the standard international classification, which can actually be directly applied to China, except for some special circumstances where the Neichiashanian and Chientangkiangian stages of the Upper Ordovician are used. Based on the new studies in recent years and distinctions and differences recognized in the development of the Ordovician System in the constituent terranes of China, a new framework for correlation among the major Chinese palaeoplates or terranes, e.g. South China, North China (including Tarim and Qaidam) and Xizang (Tibet)-western Yunnan, has been established. However, it has been recognized herein that uncertainties still remain on defining the base of the Tremadocian, Dapingian and Katian, and on the correlation between different mega-facies. More specifically, for the Tremadocian, the precise correlation of its base will depend on the better-defined conodont taxonomy, while for the Dapingian and Katian, on the correlation between different mega-facies. It is worthwhile to note that the chemostratigraphic studies of the Ordovician System in China produced the carbonate δ13C curves for the Darriwilian (Middle Ordovician) and Katian (Upper Ordovician), which show significant differences from the composite global curve. Record of the Ordovician isotopic dating is relatively rare in China, with only three reliable ages from zircons that are all from the upper Katian to Hirnantian of the Upper Ordovician. Abundant bentonite beds in the Upper Ordovician of South China will also provide unique opportunities to advance the isotopic dating and related researches. Studies on the Ordovician magnetostratigraphy need to be significantly enhanced in China, as currently all the available results are restricted to the Lower Ordovician of North China, although they can be correlated with those known from other parts of the world. The analysis of the durational unevenness of the seven stages in the Ordovician supports the possibility to further subdivide the long-durational Tremadocian, Darriwilian and Katian stages, each into two substages. [ABSTRACT FROM AUTHOR]

Cretaceous strata are widely distributed across China and record a variety of depositional settings. The sedimentary facies consist primarily of terrestrial, marine and interbedded marine-terrestrial deposits, of which marine and interbedded facies are relatively limited. Based a thorough review of the subdivisions and correlations of Cretaceous strata in China, we provide an up-to-date integrated chronostratigraphy and geochronologic framework of the Cretaceous system and its deposits in China. Cretaceous marine and interbedded marine-terrestrial sediments occur in southern Tibet, Karakorum, the western Tarim Basin, eastern Heilongjiang and Taiwan. Among these, the Himalayan area has the most complete marine deposits, the foraminiferal and ammonite biozonation of which can be correlated directly to the international standard biozones. Terrestrial deposits in central and western China consist predominantly of red, lacustrine-fluvial, clastic deposits, whereas eastern China, a volcanically active zone, contains clastic rocks in association with intermediate to acidic igneous rocks and features the most complete stratigraphic successions in northern Hebei, western Liaoning and the Songliao Basin. Here, we synthesise multiple stratigraphic concepts and charts from southern Tibet, northern Hebei to western Liaoning and the Songliao Basin to produce a comprehensive chronostratigraphic chart. Marine and terrestrial deposits are integrated, and this aids in the establishment of a comprehensive Cretaceous chronostratigraphy and temporal framework of China. Further research into the Cretaceous of China will likely focus on terrestrial deposits and mutual authentication techniques (e.g., biostratigraphy, chronostratigraphy, magnetostratigraphy and cyclostratigraphy). This study provides a more reliable temporal framework both for studying Cretaceous geological events and exploring mineral resources in China. [ABSTRACT FROM AUTHOR]

The Carboniferous period lasted about 60 Myr, from ~358.9 Ma to ~298.9 Ma. According to the International Commission on Stratigraphy, the Carboniferous System is subdivided into two subsystems, i.e., Mississippian and Pennsylvanian, including 6 series and 7 stages. The Global Stratotype Sections and Points (GSSPs) of three stages have been ratified, the Tournaisian, Visean, and Bashkirian stages. The GSSPs of the remaining four stages (i.e., the Serpukhovian, Moscovian, Kasimovian, and Gzhelian) have not been ratified so far. This paper outlines Carboniferous stratigraphic subdivision and correlation on the basis of detailed biostratigraphy mainly from South China, and summarizes the Carboniferous chronostratigraphic framework of China. High-resolution biostratigraphic study reveals 37 conodont zones, 24 foraminiferal (including fusulinid) zones, 13 ammonoid zones, 10 brachiopod zones, and 10 rugose coral zones in the Carboniferous of China. The biostratigraphic framework based on these biozones warrants the precise correlation of regional stratigraphy of China (including 2 subsystems, 4 series, and 8 stages) to that of the other regions globally. Meanwhile, the Carboniferous chemo-, sequence-, cyclo-, and event-stratigraphy of China have been intensively studied and can also be correlated worldwide. Future studies on the Carboniferous in China should focus on (1) the correlation between shallow- and deep-water facies and between marine and continental facies, (2) high-resolution astronomical cyclostratigraphy, and (3) paleoenvironment and paleoclimate analysis based on geochemical proxies such as strontium and oxygen isotopes, as well as stomatal indices of fossil plants. [ABSTRACT FROM AUTHOR]

A series of global major geological and biological events occurred during the Permian Period. Establishing a highresolution stratigraphic and temporal framework is essential to understand their cause-effect relationship. The official International timescale of the Permian System consists of three series (i.e., Cisuralian, Guadalupian and Lopingian in ascending order) and nine stages. In China, the Permian System is composed of three series (Chuanshanian, Yansingian and Lopingian) and eight stages, of which the subdivisions and definitions of the Chuanshanian and Yangsingian series are very different from the Cisuralian and Guadalupian series. The Permian Period spanned ∼47 Myr. Its base is defined by the First Appearance Datum (FAD) of the conodont Streptognathodus isolatus at Aidaralash, Kazakhstan with an interpolated absolute age 298.9±0.15 Ma at Usolka, southern Urals, Russia. Its top equals the base of the Triassic System and is defined by the FAD of the conodont Hindeodus parvus at Meishan D section, southeast China with an interpolated absolute age 251.902±0.024 Ma. Thirty-five conodont, 23 fusulinid, 17 radiolarian and 20 ammonoid zones are established for the Permian in China, of which the Guadalupian and Lopingian conodont zones have been served as the standard for international correlation. The Permian δ13Ccarb trend indicates that it is characterized by a rapid negative shift of 3-5‰ at the end of the Changhsingian, which can be used for global correlation of the end-Permian mass extinction interval, but δ13Ccarb records from all other intervals may have more or less suffered subsequent diagenetic alteration or represented regional or local signatures only. Permian δ18O{ainpatite} studies suggest that an icehouse stage dominated the time interval from the late Carboniferous to Kungurian (late Cisuralian). However, paleoclimate began to ameriolate during the late Kungurian and gradually shifted into a greenhouse-dominated stage during the Guadalupian. The Changhsingian was a relatively cool stage, followed by a globally-recognizable rapid temperature rise of 8-10°C at the very end of the Changhsingian. The 87Sr/86Sr ratio trend shows that their values at the beginning of the Permian were between 0.70800, then gradually decreased to the late Capitanian minimum 0.70680-0.70690, followed by a persistent increase until the end of the Permian with the value 0.70708. Magenetostratigraphy suggests two distinct stages separated by the Illawarra Reversal in the middle Wordian, of which the lower is the reverse polarity Kiaman Superchron and the upper is the mixed-polarity Illawarra Superchron. The end-Guadalupian (or pre-Lopingian) biological crisis occurred during the late Capitanian, when faunal changeovers of different fossil groups had different paces, but generally experienced a relatively long time from the Jinogondolella altudensis Zone until the earliest Wuchiapingian. The end-Permian mass extinction was a catastrophic event that is best constrained at the Meishan section, which occurred at 251.941±0.037 Ma and persisted no more than 61±48 kyr. After the major pulse at Bed 25, the extinction patterns are displayed differently in different sections. The global end-Guadalupian regression is manifested between the conodont Jinogondolella xuanhanensis and Clarkina dukouensis zones and the end-Changhsingian transgression began in the Hindeodus changxingensis-Clarkina zhejiangensis Zone. The Permian Period is also characterized by strong faunal provincialism in general, which resulted in difficulties in inter-continental and inter-regional correlation of both marine and terrestrial systems. [ABSTRACT FROM AUTHOR]

Ediacaran successions occur widely in various depositional facies in South China and yield a series of fossil Lagerstätten, providing a complete fossil record for the evolution of marine ecosystems after the terminal Cryogenian global glaciation. Carbonate-dominated Ediacaran successions in shallow water facies in South China record a nearly complete δ13C profile that may reflect variations of marine carbon isotopic composition during the Ediacaran Period. The Ediacaran fossils and δ13C profiles from South China permit stratigraphic correlation and subdivision of the Ediacaran strata. Based on biostratigraphic, chemostratigraphic, and geochronometric data from the Ediacaran successions in South China, we propose that the Ediacaran System in China can be subdivided into two series, with three stages in each series. The lower series is characterized by acanthomorphic acritarchs and the upper series by Ediacara-type macrofossils, and the two series are separated by the declining limb of a pronounced δ13C negative excursion (EN3) in the upper Doushantuo Formation. The basal boundary of Stage 1 is the same as the basal boundary of Ediacaran System, which has been defined at the base of the cap carbonate unit. Stage 2 represents the first radiation of Ediacaran microscopic organisms, with δ13C feature representing by positive values (EP1). The base of the Stage 2 is placed at the first appearance level of a spiny acritarch species. Stage 3 is characterized by the occurrence of more diverse acritarchs and δ13C feature EP2, with its basal boundary defined by a δ13C negative excursion (EN2) occurring in the middle Doushantuo Formation. The basal boundary of Stage 4 is the same as the upper series. Stage 5 is marked by the occurrence of macrfossils of Miaohe biota, and its lower boundary can be placed at the level where δ13C values transition from positive to negative in MNE, or the first appearance level of macrofossils of the Miaohe biota. Stage 6 is characterized by the occurrences of Ediacara-type Shibantan biota and Gaojiashan biota, with its lower boundary defined by the first appearance level of Conotubus hemiannulatus. The formal establishment of the aforementioned series and stages requires further and more detailed integrative stratigraphic study on the Ediacaran successions in China. Some of the Ediacaran successions in South China have great potential to become global standards in Ediacaran subdivision. [ABSTRACT FROM AUTHOR]

The interaction of decaying turbulence with thermal non-equilibrium (TNE) is studied using direct numerical simulations. The focus is on energy exchanges and decay rates in decaying flows with initial vibrational excitation. A key finding is the identification of different regimes in the interaction and the nondimensional parameter (β) that controls it. The latter accounts for the degree of initial TNE as well as the ratio of timescales of turbulence and vibrational relaxation. For β < 1, TNE is essentially frozen and turbulence is largely unaffected by the decay of vibrational energy. For β > 1, TNE relaxation is relatively fast and produces an increase in translational–rotational energy, which, through changes in transport coefficients, leads to a temporary increase in dissipation leading to faster turbulence decay rates. Theoretical arguments are put forth to determine the asymptotic limits of this effect. TNE relaxation is also affected by turbulent fluctuations in unexpected ways. For example, although initial conditions are always vibrationally hot, the flow may undergo vibrationally cold transients, which are explained through simple models. The results presented here help explain disagreement between previous experimental and numerical data. [ABSTRACT FROM AUTHOR]

The US Supreme Court throughout the twentieth century has been characterized as being divided between liberals and conservatives, suggesting that ideologically similar justices would have voted similarly had they overlapped in tenure. What if they had? I build a minimal, pairwise maximum entropy model to infer how 36 justices from 1946-2016 would have all voted on a Super Court. The model is strikingly consistent with a standard voting model from political science, W-Nominate, despite using 105 less parameters and fitting the observed statistics better. I find that consensus dominates the Super Court and strong correlations in voting span nearly 100 years, defining an emergent institutional timescale that surpasses the tenure of any single justice. Thus, the collective behavior of the Court over time reveals a stable institution insulated from the seemingly rapid pace of political change. Beyond consensus, I discover a rich structure of dissenting blocs with a heavy-tailed, scale-free distribution consistent with data from the Second Rehnquist Court. Consequently, a low-dimensional description of voting with a fixed number of ideological modes is inherently misleading because even votes that defy such a description are probable. Instead of assuming that strong higher order correlations like voting blocs are induced by features of the cases, the institution, and the justices, I show that such complexity can be expressed in a minimal model relying only on pairwise correlations in voting. [ABSTRACT FROM AUTHOR]

Abstract The recent introduction of post-IR IRSL measurement protocols has prompted a resurgence in luminescence applications using feldspar, some of which are affected by anomalous fading related signal loss. Many fading-corrected feldspar ages are reported in the literature, however few of those ages have been corrected using the model of Huntley (2006) [Huntley, D.J., 2006. An explanation of the power-law decay of luminescence. Journal of Physics: Condensed Matter 18(4), 1359–1365]. Here we present a new R function that calculates fading-corrected ages using the model of Huntley (2006), implemented with either a single-saturating exponential (1EXP) or general-order kinetic (GOK) fit. We evaluate the performance of the model through (i) contrasting measured and modelled field saturation values for a suite of 41 published saturated samples, and (ii) through using the model to fading-correct feldspar ages of samples with independent age control. Our results indicate that when implemented with 1EXP this model has an accuracy of 10% for predicting sample saturation, but that independent ages may be overestimated when the model is used to fading-correct samples across a range of timescales. In contrast, providing that the dose response curve has been characterised beyond 600 Gy, implementing the Huntley (2006) model with a GOK fit yields accurate age estimations. Modelled age overestimation for 1EXP is associated with dose response curve deviation from a single-saturating exponential. Finally we contrast the laboratory measured light levels of a suite of 50 saturated samples with their corresponding fading rates. We show that these saturated samples may yield D e values below 2D 0 , and thus that 2D 0 is not an effective screening criterion for sample saturation where no anomalous fading correction is made. Highlights • Fading correction of feldspar luminescence is explored using known age samples. • Dose response deviation from a single saturating exponential causes age overestimation. • A general order kinetic fit results in accurate age determination. • 2D 0 cannot be used to evaluate feldspar saturation, unless fading is corrected for. [ABSTRACT FROM AUTHOR]

Floods related to extreme precipitation events, especially intense, short‐duration precipitation, may cause significant damage in urbanized areas, including transport infrastructure, electricity networks, and property. These events are expected to increase in frequency with climate change but their characteristics, at either hourly or multi‐hourly timescales, have been little studied due to short and poor quality data records. We examine annual maximum (AMAX) hourly and multi‐hourly (3, 6, 12, and 24 hr) precipitation accumulations in the United Kingdom using a quality‐controlled hourly precipitation data set for the period 1992–2014. We describe their seasonality and diurnal cycle and use a regional frequency analysis (RFA) approach with L‐moments to produce at‐site return level estimates, and then use existing extreme precipitation regions to provide regional‐scale return levels. The analysis shows a clear seasonality and the dominant occurrence of short‐duration AMAX in summer with similar seasonality for 1 and 3 hr accumulation periods in some regions, while longer‐duration AMAX (12 and 24 hr) behave similarly to each other in all regions but are distributed over a longer period including late autumn and winter. The diurnal cycle of 1 hr AMAX indicates that most extremes occur during the afternoon, with a peak typically between 1400 and 1700, especially in southern and eastern regions. However, we also demonstrate that existing regions for UK daily extremes are not able to adequately reflect differences at shorter durations and that new regions should be created. These results provide new insights to help in designing urban drainage systems and infrastructure, including the need for new scaling relationships between sub‐daily and design accumulation periods. Percentage of 1 hr (blue) and 24 hr (orange) annual maximum rainfall (AMAX) occurring in summer for 13 UK regions between 1992 and 2014. The results demonstrate a noticeable difference in the seasonality of the 1 and 24 hr AMAX and a higher proportion of extremes in summer in southern and eastern regions. The difference in seasonality between 1 and 24 hr extremes suggests a need for improved observation‐based statistical models for hourly and multi‐hourly rainfall events. [ABSTRACT FROM AUTHOR]

During the last glacial period Northern Hemisphere climate was characterized by extreme and abrupt climate changes, so-called Dansgaard–Oeschger (DO) events. Most clearly observed as temperature changes in Greenland ice-core records, their climatic imprint was geographically widespread. However, the temporal relation between DO events in Greenland and other regions is uncertain due to the chronological uncertainties of each archive, limiting our ability to test hypotheses of synchronous change. In contrast, the assumption of direct synchrony of climate changes forms the basis of many timescales. Here, we use cosmogenic radionuclides (10Be , 36Cl , 14C) to link Greenland ice-core records to U/Th -dated speleothems, quantify offsets between the two timescales, and improve their absolute dating back to 45 000 years ago. This approach allows us to test the assumption that DO events occurred synchronously between Greenland ice-core and tropical speleothem records with unprecedented precision. We find that the onset of DO events occurs within synchronization uncertainties in all investigated records. Importantly, we demonstrate that local discrepancies remain in the temporal development of rapid climate change for specific events and speleothems. These may either be related to the location of proxy records relative to the shifting atmospheric fronts or to underestimated U/Th dating uncertainties. Our study thus highlights the potential for misleading interpretations of the Earth system when applying the common practice of climate wiggle matching. [ABSTRACT FROM AUTHOR]

We consider an ensemble of Ornstein–Uhlenbeck processes featuring a population of relaxation times and a population of noise amplitudes that characterize the heterogeneity of the ensemble. We show that the centre-of-mass like variable corresponding to this ensemble is statistically equivalent to a process driven by a non-autonomous stochastic differential equation with time-dependent drift and a white noise. In particular, the time scaling and the density function of such variable are driven by the population of timescales and of noise amplitudes, respectively. Moreover, we show that this variable is equivalent in distribution to a randomly-scaled Gaussian process, i.e., a process built by the product of a Gaussian process times a non-negative independent random variable. This last result establishes a connection with the so-called generalized grey Brownian motion and suggests application to model fractional anomalous diffusion in biological systems. [ABSTRACT FROM AUTHOR]

In this work, we introduce a new change of coordinates, which we term local orthogonal rectification, or LOR, that can be applied at any selected curve in the phase space of a dynamical system. LOR, based on the Frenet frame, yields a coordinate system, the LOR frame, which allows us to rigorously study curves that are nearly invariant in the flow. We use the LOR approach to derive a novel definition for rivers, long-recognized but poorly understood trajectories that locally attract other orbits yet need not be related to invariant manifolds or other familiar phase space structures, and to identify rivers within several example systems. We show that our new definition of rivers connects nicely with the curvature of trajectories and that our approach provides a way to handle the ''ghost" phenomenon of falsely identified candidate structures described in past analysis of the zero-curvature locus of a flow. We also apply the LOR approach to locate the periodic orbit in a FitzHugh--Nagumo system and to study its parameter dependence. Finally, we extend the approach to an asymptotic setting that, as we show, can be used to track invariant manifolds in multiple-timescale systems far from the limit of strong timescale separation. [ABSTRACT FROM AUTHOR]

Highlights • Historical disciplines offer important human-scale data about climate-adaptation. • Global change researchers can use historical data to inform scenario planning. • We present a 'new social contract' for collaboration between historical and global change disciplines. • Co-designing and publishing synthesised research and communicating historical information in museums. Abstract We argue that the deep time perspectives offered by historical disciplines, such as archaeology and history, provide important human-scale data about climate-adaptation over long timescales, and that these insights are currently lacking in global change research and Intergovernmental Panel on Climate Change reports. Pre-modern societies are not comparable with contemporary societies, but the completed experiments they represent can offer evidence of the consequences of climate change, the challenges of uncertainty and socio-cultural limits to adaptation. The limited visibility of data on long-term human interactions with climate change in global change research could be overcome through a 'new social contract', a two-way movement between global change and historical disciplines to, 1) make use of, and apply, historical data to contemporary climate-related challenges, 2) design robust interdisciplinary, and transdisciplinary research, 3) publish synthesised research in high-impact climate-adaptation journals, and 4) communicate research to the public in cultural history museums. [ABSTRACT FROM AUTHOR]

The reversal frequency of the palaeomagnetic field bears great information of evolution of Earth's deep interior. However, there are still debates on the frequency pattern during the older periods of the Phanerozoic. This study investigated the Niutitang Formation (Lower Cambrian) of the Ciye 1 Hole from South China. Rock magnetic results indicate that the dominant magnetic carrier is magnetite. Characteristic remanence magnetizations have been successfully isolated for the weakly magnetized shale rocks through stepwise alternated field demagnetization using the 2G Enterprises Rapid System Magnetometer with a low-noise thin-walled quartz-glass sample holder. Constrained by radiometric ages, our palaeomagnetic results indicated frequent polarity reversals during the period of ∼524–514 Ma, which backs up the speculation about the episode of the Ediacaran–Cambrian (∼550–500 Ma) with a character of reversal hyperactivity. [ABSTRACT FROM AUTHOR]

Precipitation isotope reconstructions derived from speleothems and plant waxes are important archives for understanding hydroclimate dynamics. Their climatic significance in East Asia, however, remains controversial. Here we present terrestrial plant-wax stable hydrogen isotope ( δ D wax ) records over periods covering the last four interglacials and glacial terminations from sediment cores recovered from the northern South China Sea (SCS) as an archive of regionally-integrated precipitation isotope changes in Southeast China. Combined with previous precipitation isotope reconstructions from China, we find that the SCS δ D wax and Southwest-Central China stalagmite δ 18 O records show relatively enriched and depleted isotopic values, respectively, during interglacial peaks; but relatively similar isotopic variations during most sub-interglacials and glacial periods over the past 430 thousand years. During interglacial peaks, strong summer insolation should have intensified the convection intensity, the isotopic fractionation along moisture trajectories and the seasonality, which are all in favor of causing isotopically-depleted rainfall over the East Asian monsoon regime. These effects in combination with a relatively high proportion of Indian Ocean- versus Pacific-sourced moisture influx should have resulted in strongly depleted precipitation isotopes (stalagmite δ 18 O) over most parts of China. However, Southeast China should have been affected by a relatively low ratio of Indian Ocean- versus Pacific-sourced moisture influx, which dominated over effects yielding depleted precipitation isotopes and led to enriched precipitation isotopes ( δ D wax ). It is thus concluded that glacial boundary conditions and insolation forcing are the two most important factors for causing regional differences in precipitation isotope compositions over subtropical East Asia on orbital timescales. [ABSTRACT FROM AUTHOR]

We study the dynamics of secondary infections on networks, in which only the individuals currently carrying a certain primary infection are susceptible to the secondary infection. In the limit of large sparse networks, the model is mapped to a branching process spreading in a random time-sensitive environment, determined by the dynamics of the underlying primary infection. When both epidemics follow the Susceptible-Infective-Recovered model, we show that in order to survive, it is necessary for the secondary infection to evolve on a timescale that is closely matched to that of the primary infection on which it depends. [ABSTRACT FROM AUTHOR]

We introduce the Schwarzian, simplified Schwarzian, and Schwarzian Korteweg-de Vries equations on a time scale that are invariant under the fractional linear transformations. As an application, we derive their solutions and establish the invariant disconjugacy condition for second order dynamic equations on a time scale. Furthermore, we consider the Ermakov dynamic equation and the Ermakov-Lewis adiabatic invariant on a time scale. We discuss specific examples of discrete, quantum, and continuous time scales to compare our equations with the well-known ones. We also derive the linearization of the Ermakov equation and the corresponding Painleve equation on a time scale. [ABSTRACT FROM AUTHOR]