Miracle-dz/UniFAR-FTUs huggingface dataset:
A dramatic climatic transition at ~4000 cal. yr BP and its cultural responses in Chinese cultural domains

Our review of recently published climatic proxy sequences shows that the most dramatic climate tranistion of the mid Holocene (~8500–~3500 cal. yr BP) occurred at the middle- to late-Holocene transition at ~4000 cal. yr BP. In northern China, an abrupt climatic shift at ~4000 cal. yr BP was recorded in the eastern margin of the Tibetan Plateau, in the western part of the Chinese Loess Plateau and in the vast Inner Mongolian Plateau. In southern China, the ~4000 cal. yr BP event was also abrupt, but it is expressed as one of several quasi-cyclic events in most of the records. We propose that the cumulative effects of insolation-dictated declining trend in tropical SST and the geologically documented increasing trend of ENSO activity were the first-order causes of the cooling and the associated drying during the past 6000 years. Superimposed on the first-order causes were the second-order causes, i.e. the additive effects of the ‘Bond Event 3’-associated lower insolation and the increasingly drying-resulted negative feedback of ‘air–land interactions’. The second-order causes made ~4000 cal. yr BP the tipping point when the resultant drying had destroyed many Chinese Neolithic cultures. Our review of published archaeological literature shows that six of the seven well-documented Chinese Neolithic cultures collapsed at ~4000 cal. yr BP with the exception of the Henan Longshan Culture that evolved to the more advanced Erlitou Culture. The indicators of the cultural collapse include (1) the number of archaeological sites was significantly reduced, (2) the quality of the archaeological artifacts of the succeeding culture is lower than that of the preceding culture, (3) more sophisticated architectures disappeared, and (4) agricultural cultures were replaced by pastoralism or by agro-pastoralism in northern China.
Mechanisms of dike propagation in layered rocks and in massive, porous sedimentary rocks

The mechanisms of dike propagation are analyzed through detailed examination of small structures associated with the dike intrusion. Exposures in the Ramon area, Israel, offer an opportunity to evaluate theoretical models of tensile fracture propagation and to better understand the factors governing the dike geometry. Dike-related structures are studied in two Jurassic units: the Ardon Formation, a well-stratified sequence of shales and dolomites, and the Inmar Formation, which is composed of porous, massive sandstones with a few shale lenses. It is shown that for the different host rocks the propagation mechanisms and structures differ significantly. Dikes in the Ardon Formation are dominated by 1–20 m wide segments, confined to distinct layers. The mechanisms of segment containment are determined by calculating the stress intensity factor for an extension crack approaching a mechanical interface. It is apparent that dike segmentation and containment is controlled mainly by in situ stress and shear moduli differences between adjacent layers and partly by bedding plane slippage. Dikes in the Inmar Formation are dominated by smaller segments and by 1–10 cm wide and 10–100 cm long fingers with intermittent smooth patches and slickensides. Opposite dike walls display exact mirror images of these features. Dikes propagate in alternating stages of viscous flow and brittle deformation. The viscous stages include fluidization of the sandstone by the dike-related fluids and increase of the pore pressure in the rock. A viscous instability develops between the highly viscous fluidized sandstone and the less viscous dike-related fluids, forming a zone of viscous fingering in front of the dike. Stages of brittle fracturing occur when the pore pressure is released and the flux of fluids is insufficient to fluidize the rock.
Calibration of an ML Scale in northwestern Turkey from 1999 Izmit aftershocks

A local magnitude scale is derived for northwestern Turkey, using data collected by a temporary network installed by the German Task Force for Earthquakes after the 1999 Izmit earthquake ( M w 7.4) and the permanent Sapanca-Bolu network. We computed Wood–Anderson seismograms for over 5353 arrivals at 27 three-component stations, from 530 earthquakes. The hypocentral distances considered range from 5 to 140 km, with the best represented range being from 5 to 70 km. We inverted the measured amplitudes following both the nonparametric Richter's (1958) and parametric Bakun and Joyner (1984) approaches. These methods yield consistent magnitude values and station corrections. However, the calculated nonparametric distance correction, log A , implies that ground-motion attenuation is higher than what is accounted for by the equation calibrated in central California. In the range 5–62 km, the best fit is provided by -log A = log( R /17) + 0.00960( R - 17) + 2. This equation is obtained constraining the geometrical spreading parameter n to 1. The calculated value of k = 0.00960 confirms that in this range of distance seismic waves could propagate through a low- Q volume. Station corrections, which allow for a significant reduction of M L residuals, range between ±0.5 magnitude units, suggesting a strong influence of local site effects on the amplitude of ground motion. In accord with the obtained attenuation and station corrections, the magnitudes of the considered events range from 0.4 to 4.8.
The spatial coherence of interannual temperature variations in the Antarctic Peninsula

The west coast of the Antarctic Peninsula is a region of extreme interannual variability in near‐surface temperatures. Recently the region has also experienced more rapid warming than any other part of the Southern Hemisphere. In this paper we use a new dataset of satellite‐derived surface temperatures to define the extent of the region of extreme variability more clearly than was possible using the sparse station data. The region in which satellite surface temperatures correlate strongly with west Peninsula station temperatures is largely confined to the seas just west of the Peninsula. Correlation of Peninsula surface temperatures with those over the rest of continental Antarctica is poor confirming that the west Peninsula is in a different climate regime. Our analysis suggests that only one of five existing ice cores from the region is likely to provide a proxy climate record that is representative of the west coast.
An intense cyclonic eddy east of the Mozambique Ridge

Data from cruises of the Meiring Naude in 1978 delineated an intense cyclonic eddy in the vicinity of 30°S, 38°E and extending to a depth of more than 1800 m. Between May and June 1978 the eddy advected to the southeast at 5 cm s−1. The eddy was elliptical (90×240 km), and the volume transport varied between 20 and 48×106 m3 s−1.
2023 International Olympic Committee’s (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs)

Relative Energy Deficiency in Sport (REDs) was first introduced in 2014 by the International Olympic Committee’s expert writing panel, identifying a syndrome of deleterious health and performance outcomes experienced by female and male athletes exposed to low energy availability (LEA; inadequate energy intake in relation to exercise energy expenditure). Since the 2018 REDs consensus, there have been >170 original research publications advancing the field of REDs science, including emerging data demonstrating the growing role of low carbohydrate availability, further evidence of the interplay between mental health and REDs and more data elucidating the impact of LEA in males. Our knowledge of REDs signs and symptoms has resulted in updated Health and Performance Conceptual Models and the development of a novel Physiological Model. This Physiological Model is designed to demonstrate the complexity of either problematic or adaptable LEA exposure, coupled with individual moderating factors, leading to changes in health and performance outcomes. Guidelines for safe and effective body composition assessment to help prevent REDs are also outlined. A new REDs Clinical Assessment Tool-Version 2 is introduced to facilitate the detection and clinical diagnosis of REDs based on accumulated severity and risk stratification, with associated training and competition recommendations. Prevention and treatment principles of REDs are presented to encourage best practices for sports organisations and clinicians. Finally, methodological best practices for REDs research are outlined to stimulate future high-quality research to address important knowledge gaps.
Characterization and Classification of Rocks with Lamb Modes

The nondestructive investigation by ultrasound has become a fundamental tool for characterizing rocks. We applied this technique for characterizing samples of rocks. The later had been members of the following three big families of geogical classification: magmatic rocks, metamorphic rocks, sedimentary rocks. The method usually used is based on the measurement of ultrasound parameters, i.e. the longitudinal and transversal propagation velocities. The measurement of these parameters allows to determine the mechanical properties of each rock. These studies do not allow to find the three big axes of the rocks. In this work we show for each rock his corresponding ultrasonic signature by the use of his experimentally determined Lamb dispersion curves. The obtained results put in evidence that the descending slope of the Lamb modes is a reliable and efficient criterion for classifying rocks by ultrasound. This is an adequate solution for a good classification of rocks. It gives a high precision, it is reliable and quick and last not least cheap.
Geochemistry of north Cleft segment vent fluids: Temporal changes in chlorinity and their possible relation to recent volcanism

Hydrothermal vent fluids from the North Cleft segment of the Juan de Fuca Ridge between 44°54′ and 45°00′N were sampled in 1988, 1990, 1991, and 1992. In 1988, chloride-depleted (relative to seawater) diffuse fluids with low dissolved metal concentrations (relative to other mid-ocean ridge (MOR) fluids) were sampled over a distance of ∼10 km along axis. In 1990 and 1991, both high-temperature (>200°C) and diffuse vents were consistently metal- and chloride-enriched. The end-member compositions of high-temperature vents and nearby diffuse vents were very similar. There were small but significant correlated changes in diffuse and high-temperature composition from 1990 to 1991. The large-scale but temporary venting of low-chlorinity fluids over the entire North Cleft segment provides a resolution to the apparent mass imbalance implied by observations of continuous venting of chloride-enriched fluids. It is possible that a volcanic event along the North Cleft segment prior to 1987, for which there is firm geologic evidence, initially caused a boiling event which resulted in the preferential venting of vapor-enriched fluids through 1988, followed by a transition to brine-enriched fluids by 1990. High iron, low sodium, and low Sr/Ca ratios in the high-chlorinity fluids suggest that the brine phase has continued to react and approach reequilibration with an alteration mineral assemblage after the phase separation event. The absence of chloride-depleted fluids from 1990 onward, and the systematics of lithium, boron, and manganese with chloride in the high-temperature fluids from North Cleft suggest that the evolution toward lower chlorinity at Monolith vent from 1990 to 1992 is caused by progressive dilution of a brine with hydrothermal seawater.
Lateglacial environmental changes recorded in calcareous gyttja deposits at Gulickshof, southern Netherlands

Environmental changes were reconstructed from Lateglacial calcareous gyttja deposits at Gulickshof, southern Netherlands. Analyses of pollen, fresh‐water mollusca, stable isotopes and geo‐chemistry were performed and the combined evidence was put into a chronostratigraphic framework based on regional biostratigraphy and accelerator mass spectrometry radiocarbon dating. The pollen diagram showed vegetation development from the Bφlling interstadial into the Late Dryas stadial within 2.9 m of lacustrine deposits. Early in the Allerφd, around 11 900 BP, the composition of aquatic taxa and stable isotopes of calcium carbonate changed significantly. It appears that the final melting of relic ground‐ice and subsequent re‐establishment of the hydrological cell early in the Allerφd were responsible for these changes. Later in the Allerφd, around 11 250 BP, the disappearance of molluscs, changes in vegetation and isotope composition all point to colder climate conditions attributable to the Gerzensee oscillation. The combination of different lines of evidence in these types of deposits proves to be an excellent tool for unravelling climate and environmental signals.
The Evolution of Top Incomes: A Historical and International Perspective

This paper summarizes the main findings of the recent studies that have constructed top income and wealth shares series over the century for a number of countries using tax statistics. Most countries experience a dramatic drop in top income shares in the first part of the century due to a precipitous drop in large wealth holdings during the wars and depression shocks. Top income shares do not recover in the immediate post war decades. However, over the last 30 years, top income shares have increased substantially in English speaking countries but not at all in continental Europe countries or Japan. This increase is due to an unprecedented surge in top wage incomes starting in the 1970s and accelerating in the 1990s. As a result, top wage earners have replaced capital income earners at the top of the income distribution in English speaking countries. We discuss the proposed explanations and the main questions that remain open.
Ground Survey Methods for Mixed Sand and Gravel Beaches in Intertidal Environments: A Comparison

Abstract An assessment of variation in beach volumes is needed to better understand beach behaviour and to monitor changes in an attempt to manage beach volume distribution through targeted intervention. Mixed sand and gravel beaches, as well as gravel beaches, are distinct from sandy beaches in that they often have multiple steep (>20° or 1 : 4) berms on the upper part of the beach and short-wavelength (<20 m) longshore variations in the form of beach cusps or in close proximity to groynes. This paper discusses a range of ground survey and remote sensing methods for surveying mixed beaches, methods of point collection in relation to the different methods, and subsequent interpolation to calculate beach volumes. Particular emphasis is given to high-density surveys by Global Positioning System (GPS) with a rover attached to a wheel. Results show that average surface elevation changes greater than ±0.04 m can be reliably detected and that the method, if carried out using cross-shore profiles, provides a useful tool for beach monitoring in scientific projects interested in inferring processes from the surveys and that have a temporal resolution from tides to weeks. For surveys predominantly interested in monitoring total beach volume, GPS surveys with a quad bike (all-terrain vehicle) might be more economical while providing only marginally poorer results if surveys coincide with minimum cross-shore variation during spring tide. Comparisons between ground surveys with GPS and remote sensing methods like LIDAR or airborne photogrammetry are also discussed.
Are we ready for the new normal in e-business education? Sentiment analysis of learners' opinions on MOOCs

Introduction. The new digital economy and its constantly evolving paradigm have completely transformed the model of doing business and the learning methods. MOOCs (massive-open-online-courses) and micro-credentials are the educations interfaces, have become an important teaching environment tool. Distance learning has become an indispensable alternative teaching method in updating and transferring classical education materials according to real-world settings, especially for learners in higher education.Aim. The current research is aimed to address the society's readiness and attitude direction to the concept of MOOCs and distance learning, highlighting its emergence and inevitability for educational institutions of all types in order to make a fundamental change in their curricula, especially in e-business courses, which are the most demanded training courses on MOOCs platforms.Methodology and research methods. In the study, the awareness and recognition of the online community on the MOOCs concept is examined. In this direction, Turkish people's perception and attitudes toward MOOCs have been addressed via sentiment analysis on Eksi Sozluk, the largest social communication and discussion platform in Turkey.Results. According to the sentiment analysis results, it has been determined that 52% of respondents have positive judgments on distance education and MOOCs, 29% of responses are neutral and 18% are negative. In general, distance education and MOOCs are perceived as a useful new education model by the Turkish people.Scientific novelty. This paper is the first sentiment analysis of learners' opinions on MOOCs and distance learning in Turkey. Considering the increasing awareness of MOOCs and the need for e-business education, as the most demanded type of MOOCs, this is the first study investigating the priority of these two phenomena within the context of COVID-19.Practical significance. It is thought that this study will contribute to the stakeholders in terms of showing how MOOCs and micro-credentials have a high potential to understanding trends in education especially in the new normal after the COVID-19 pandemic. The holistic education model of institutions has difficulty meeting the competitive nature and result-oriented approach of the e-business ecosystem. This market reality requires the institutions to offer more to-the-point and applied education solutions. In terms of e-business (e-commerce, digital marketing) education, the importance of MOOCs as a solution-focused on “how” rather than “what” has been comprehensively discussed in the paper.
The ICDP Lake Bosumtwi impact crater scientific drilling project (Ghana): Core LB‐08A litho‐log, related ejecta, and shock recovery experiments

Abstract— The 1.07 Myr old Lake Bosumtwi impact crater in Ghana was drilled within the framework of the International Continental Scientific Drilling Project (ICDP). Hole LB‐08A, drilled into the outer flank of the central uplift and with a total depth of 451 m, yielded 215.71 m of impact‐related rocks. This paper summarizes observations of the lithological logging on core LB‐08A. Between a depth of 235.6 and ∼260 m, the section consists of a melt‐bearing allochthonous, polymict, and mostly clast‐supported impact breccia. Down to ∼418 m, the section comprises a rather uniform unit of meta‐graywacke alternating with phyllite to slate (lower greenschist facies); few (par‐) autochthonous impact breccia bodies and rare impact dike breccias are present. The lowermost part of the section contains several centimeter‐ to decimeter‐thick melt‐bearing breccia dikes in country rocks identical to those occurring above. Omnipresent fracturing was mapped in a qualitative manner. Most prominent shock effects in the uplifted target rocks comprise planar fractures and deformation elements in quartz and polysynthetic twinning in carbonate minerals; the maximum shock pressure as evidenced by quartz is below 26 GPa. The allochthonous breccias occasionally contain a few vol% of melt particles. Suevites occur outside the crater rim, carrying diaplectic crystals, coesite, and ballen quartz as well as true melt glasses and a variety of lithic clasts, among those spectacular staurolite‐rich mica‐schists. The recorded shock level in the uplifted target rocks is lower than expected and modeled. Shock recovery experiments with analogue carbonaceous graywackes at 34 and 39.5 GPa yielded nearly complete transformation of quartz into diaplectic glass. We therefore exclude a specific shock behavior of the soft, fluid‐rich target material (carbonaceous graywackes, shales, slates) in core LB‐08A as the prime or only reason for the melt deficit and the generally low shock levels recorded inside the Lake Bosumtwi impact crater.
A new basal dicynodont from the Upper Permian of South Africa

The skull of a small anomodont therapsid, from the Tapinocephalus Assemblage Zone (Abrahamskraal Formation, Beaufort Group, Upper Permian) in Northern Cape Province, South Africa, represents a new basal dicynodont and is described in detail. Colobodectes cluveri gen. et sp. nov. is distinguished from other dicynodonts by an anteroposteriorly extensive caniniform process, parietals that were broadly overlapped posterolaterally by posterodorsal processes of the postorbitals, diverging anterior palatal ridges, and a dorsoventrally low foramen magnum. A phylogenetic analysis indicates that Colobodectes is the basalmost member of a dicynodont clade that excludes Eodicynodon. This position is not particularly strong, as two additional steps are needed to make Colobodectes and Eodicynodon oosthuizeni exchange places on the most parsimonious tree. Another discovery of the phylogenetic analysis is that there is little basis for recognizing Eodicynodon oelofseni as the closest relative of E. oosthuizeni. The former species is identified as the sister taxon of a clade that includes the latter and all other dicynodonts.
The solar spectral irradiance 1200–2550 Å at solar maximum

Full-disk solar solar spectral irradiances at solar maximum were obtained in the spectral range 1200--2550 A at a spectral resolution of approximately 1 A from rocket observations above White Sands, New Mexico, on June 5, 1979. Comparison with measurements made near solar minimum indicates approximately a factor of 2.5 increase in the irradiance at 1200 A, a 20% increase near 1800 A, and no increase within our measurement errors ( +- 15%) above 2100 A. Irradiances in the range 1800--2100 A are in excellent agreement with previous measurements, but those in the 2100- to 2550-A range are significantly lower. The intensities of strong emission lines at wavelengths below 1850 A are also reported.
Reconnection at the dayside magnetopause: Comparisons of global MHD simulation results with Cluster and Double Star observations

[1] This study uses two conjunctions between Cluster and Double Star TC-1 spacecraft together with global magnetohydrodynamic (MHD) simulations to investigate the large-scale configuration of magnetic reconnection at the dayside magnetopause. Both events involve southward interplanetary magnetic fields with significant By components. The first event occurred on 8 May 2004, while both spacecraft were exploring the dawn flank of the magnetosphere; TC-1 was skimming the magnetopause whereas Cluster was exploring higher latitudes. Results from a global MHD simulation show the formation of an equatorial merging line in the morning sector and suggest that the three-dimensional geometry of the merging region is mostly a radial juxtaposition of planes displaying X-type reconnection geometries. The second conjunction was on 6 April 2004. During this event, Cluster was located at high latitudes and close to the noon-midnight meridian, while TC-1 was exploring the dawnside at low latitudes. Analysis of the simulation reveals that both antiparallel and component merging occurred simultaneously. Three-dimensional rendering of the parallel electric field indicates that component merging initiated in the subsolar magnetopause. Simulation runs carried out using different parameters in the model suggest that the spread of the merging region depends on the local resistivity. The subsolar-merging region grows with increasing resistivity values and becomes patchy when a resistivity threshold is used. However, the region of component merging appears to remain spatially constrained to the subsolar region where stronger parallel electric fields occur and no clear connection with the antiparallel-merging regions is found for the range of parameters surveyed.