Miracle-dz/UniFAR-FTUs huggingface dataset:
Chemical distinction between lithogenic and pedogenic iron oxides in environmental magnetism : a search for the perfect solution

One of the goals in environmental magnetism is to understand the link between climate change and the characteristics of magnetic particles in rocks, soils and sediments. Rock-magnetic analyses sometimes are non-unique, which hinders an unambiguous identification of the magnetic particles that carry the climatic information. In this thesis, several complementary methods from chemistry and soil science are examined to explore whether they can assist in improving the determination of mineral-magnetic climate proxies. The first two parts of this thesis describe the results of tests with chemical extraction techniques (CBD and AAO-Fe2+ methods) on natural samples from a Czech loess-paleosol sequence as well as synthetic samples. The results indicate that both methods remove part of the pedogenic (climatically influenced) iron oxides, although in a varying degree. Neither method was able to remove the newly formed pedogenic particles with sufficient efficiency without affecting the lithogenic fraction as well. In combination with new mineral-magnetic techniques (FORC diagrams and automated IRM component analysis) the extraction methods did provide valid information about the composition of the samples which could not be retrieved from standard rock-magnetic data alone. A new technique in electrochemistry (voltammetry of microparticles) is discussed in the final part of this thesis. This technique was tested here for the first time on natural loess and paleosol samples to determine whether it is suitable for identifying and quantifying the magnetic mineral composition in natural samples. The results indicate that the technique is well suited for identifying as well as quantifying the weak magnetic minerals such as hematite, even when these are present in small amounts. With this thesis we have introduced and improved techniques for determining the magnetic mineral composition of natural samples, and the results have brought us a step closer to understanding the climate signal of magnetic particles in soils and sediments.
Structural Configuration of the Early Cretaceous Cordilleran Foreland‐Basin System and Sevier Thrust Belt, Utah and Colorado

Stratigraphic and provenance data from Lower Cretaceous rocks in Utah and Colorado and structural evidence from the Sevier belt in west‐central Utah allow recognition of the ties between early thrust‐belt evolution and foreland‐basin system development. Regional isopach patterns of Lower Cretaceous strata define foreland‐basin system depozones. Lower Cretaceous strata in west‐central Utah that thicken westward from ∼100 m to ∼1.2 km were deposited within the flexurally subsiding foredeep depozone. Correlative units in eastern Utah and western Colorado <100 m thick were deposited in the forebulge depozone while Lower Cretaceous rocks in central Colorado >∼100 m thick were deposited in the back‐bulge depozone. These thickness trends indicate the Lower Cretaceous foreland‐basin system consisted of a foredeep ∼100–180 km wide and forebulge ∼260–460 km wide. A computer‐generated flexural model of the foreland‐basin system produces a reasonable match of the observed basin geometry using a 400‐km‐wide load with a maximum elevation of 2.5 km located in western Utah. The load used in the model is similar to restored, balanced structural cross sections of the Sevier thrust belt that indicate thrust loads associated with the Canyon Range and Pavant thrusts were at the same location and of similar magnitude during Early Cretaceous time.
Wh-questions in Spanish: meanings and Configuration Variability

This paper describes the distinct tonal configurations of wh-questions in Spanish and discusses their possible correlations with pragmatic and interactional meanings. The data consisted of both read and spontaneous speech from four Latin American varieties. Two of the dialects, Mexican and Colombian, as opposed to Venezuelan and Puerto Rican, showed a marked preference for rising contours in read speech, while in interviews virtually no such contours occurred for any of the speakers. A different kind of rising contour did regularly occur in the natural speech data, a globally rising contour without a dip before the final high rise, used for confirmation or reprise whquestions. The conclusion of this study is that the unmarked configuration is indeed the gradually descending one, as described in the literature. This applies to all the dialects here examined, in spite of the variability of the contours, which is context-induced and related to information structure.
The upper mantle beneath Ninetyeast Ridge and Broken Ridge, Indian Ocean, from surface waves

Summary The Rayleigh wave group velocities are used to determine the upper mantle structure of the aseismic ridges of the eastern Indian Ocean, i.e. the Ninetyeast Ridge and the Broken Ridge-Naturaliste Plateau. For comparison, profiles are studied across the Bay of Bengal and to the west of the Ninetyeast Ridge. The group velocities are associated with the regions by the pure path method. Models are obtained down to 150-200 km for the profiles on and off Ninetyeast Ridge, and down to 100km for Broken Ridge. They reveal that, except for a thick anomalous crust, the structure beneath these ridges is quasi-oceanic. For the Ninetyeast Ridge, however, the uppermost 30 km of the mantle have lower velocities; such low velocities are also obtained for the Walvis Ridge by Chave. For the paths off ridge no such low velocities are obtained, indicating a small lateral extension of this anomaly. A thermal origin is ruled out, while a model with serpentinized peridotites as proposed by Bowin, which fits the gravimetric data, is able to explain the low velocities of the uppermost mantle beneath the Ninetyeast Ridge.
The distribution of olivine in the Crater Aristarchus inferred from Clementine NIR data

Clementine imaged the Moon entirely at eleven wavelengths. This paper presents new results obtained on the crater Aristarchus using a heuristic method for the calibration of the near infrared (NIR) data set. We computed band ratios and we extracted spectra using a telescopic spectrum as reference. A new ∼4×10 km olivine rich area has been identified on the southeastern rim of the crater, in addition to a smaller olivine rich area previously reported. The olivine to pyroxene ratio exceeds 6 in this new zone. This demonstrates the uniqueness of the Clementine NIR data set in discriminating olivine from pyroxene on the lunar surface, with implications for magmatic processes in the lunar mantle and crust.
Numerical modelling of generation, propagation and run‐up of tsunamis caused by oceanic impacts: model strategy and technical solutions

SUMMARY Hypervelocity impacts of asteroids in marine environments produce tsunami waves independent of the water depth and the diameter of the projectile. However, the characteristics of the induced waves are affected by these parameters. We present a model, consisting of the wellknown SALE impact model and a non-linear wave propagation model, to study the generation and subsequent spread out of the initial wave pattern caused by the strike of an asteroid or comet in the ocean. The numerical simulation of oceanic impacts requires some changes and extensions to the original SALE code. Especially, the handling of different materials (water and solid rocks) is crucial as they are involved in the cratering process. For the simulation of the propagation of tsunami waves that are generated by the impact process we use a newly developed wave propagation model, which is based on the non-linear shallow water theory with boundary conditions derived from the impact model. The run-up of the tsunami wave on the coastline is implemented as a special case of reflection and is realized by the wellestablished MOST code. Besides the model description we exemplify the capability of our modelling scheme by the simulation of the strike of an asteroid 800 m in diameter on a 5000-m-deep ocean at 10.2 km s −1 , the subsequent propagation of the induced tsunami waves over an artificial bathymetry and the run-up of the wave on the coast.
A STUDY OF THE STRUCTURE OF THE TURBULENT BOUNDARY LAYER WITH AND WITHOUT LONGITUDINAL PRESSURE GRADIENTS

Abstract : The existence of three regions of the turbulent boundary layer, each correlating with a distinct part of the non-dimensional mean velocity profile, was confirmed; these are: (a) wake or intermittent region (b) fully turbulent region (c) wall layer region. Details of the flow structure of these regions were further verified using a new hot-wire anemometer and an improved combined-time-streak marker hydrogen-bubble technique. Instantaneous spanwise velocity profiles over a large extent of the flow at many fixed y-positions across the layer were obtained. The study of the flow structure was extended to include both positive and negative pressure gradient flows, including a relaminarization flow. The hot-wire anemometer provided a means of obtaining detailed mean velocity profiles well within the sublayer region. The hydrogen-bubble combined-time streak marker visualization technique was shown to be a useful tool for quantitative measurement of time-dependent velocity fields. (Author)
Geomorphic and Coastal Process Analysis for Ship Channel Planning at Ship Island, Mississippi

Abstract : Westward migration of Ship Island, Mississippi, has resulted in significant channel shoaling and increased maintenance dredging requirements of the Gulfport Harbor Ship Channel, requiring realignment of the channel to the west around the advancing island tip. The western island tip has migrated westward approximately 38 ft/year since 1848. The subaerial island area has decreased at the rate of 4.5 acres/year since 1948. As the Ship Island barrier system migrates westward, the gulf shoreline along the eastern end erodes, supplying sand to the advancing western tip. Alternative channel alignments were studied as potential solutions to the shoaling problems caused by the island migration. An alignment passing 1,900 ft west of the island tip would allow approximately 50 years before the island tip reaches the channel edge, based on the 38 ft/year migration rate. This alignment is favorable according to the following criteria: construction and maintenance costs as a function of dredging requirements; channel navigability; siltation potential; and complexity of design and construction. Keywords: Shallow water; Sediment transport; Channel(waterways); Water waves; Barrier island; Bathymetric analysis; Historic data; Shoaling; Wave refraction. (sdw)
A quantitative study of gap recolonization in two contrasted limestone grasslands

Gaps differing in size, form and season of origin (September 1978 and March 1979) were created artificially in adjacent north- and south-facing grasslands in North Derbyshire. Detailed measurements revealed marked differences between the two sites in patterns of vegetative regrowth and regeneration from seed. Specific effects of gap type and time of origin were detected on both slopes. Creation of gaps exerted pronounced effects upon the relative abundance of established components of the north-facing turf. Accumulations of bryophytes were considerably less after three years than in undisturbed turf and Avenula pratensis tended to be reduced in comparison with potentially faster-growing species such as Plantago lanceolata and Holcus lanatus. Effects of comparable magnitude were not induced on the southfacing slope and it is suggested that this may be related to the high level of disturbance normally experienced by the vegetation on this slope. On the north-facing slope where seedlings are comparatively scarce in undisturbed turf, gap creation promoted spring germination in species which maintain relatively persistent seed reserves at or near the soil surface. In marked contrast on the south-facing slope, large numbers of seedlings appeared in the autumn in both gaps and control areas. Such patterns are consistent with previous laboratory studies which revealed differences in germination requirements between the species concerned. On the south-facing slope seedling survival was often highest in areas where resprouting vegetative shoots were relatively dense. However, the benefit of this apparent 'shelter effect' rarely extended to seedling size which tended to decline in close proximity to vigorous vegetative shoots. In the concluding section of the thesis, the main results of the investigation are reviewed in relation to the influence of aspect upon vegetation structure, current theories on the determinants of 'species richness' and opportunities to control species composition by more informed grassland management.
Raingauge quality-control algorithms and the potential benefits for radar-based hydrological modelling

Raingauges and weather radar are essential sources of rainfall information for hydrological modelling and forecasting. However, significant errors in raingauge time-series can drastically affect raingauge-only and combined radar-raingauge rainfall estimates. In turn, these errors can have a negative impact on hydrological model calibration, performance and failure diagnosis. This study considers the automated quality-control of 15 minute rainfall totals obtained from 981 tipping-bucket raingauges across England & Wales. The Grid-to-Grid distributed hydrological model, now operated by the Flood Forecasting Centre in support of national flood warning, is used with gridded rainfall estimates to assess the utility of the raingauge quality-control procedures. Although a historical dataset is used here for demonstration and assessment purposes, the automated algorithms have been designed for implementation in real-time.
Response of the intertropical convergence zone to zonally asymmetric subtropical surface forcings

The energetic framework predicts no shift of the zonal mean Intertropical Convergence Zone (ITCZ) in response to zonally asymmetric forcings (zonal warming and cooling regions with zero zonal mean) assuming radiative feedbacks are linear. Here we show the ITCZ shifts southward in response to a zonally asymmetric forcing in the Northern Hemisphere subtropics in a slab ocean aquaplanet model. The southward shift is consistent with decreased zonal mean energy input to the atmosphere due to cloud radiative effect changes in the cooling region. When cloud‐radiative feedbacks are disabled the ITCZ shifts northward consistent with changes in the warming region where increased energy input via surface heat fluxes and stationary Rossby‐wave transport dominate. Competition between cooling and warming regions leads to changes in gross moist stability. Our results show rectification of zonally asymmetric forcings play an important role in zonal mean ITCZ dynamics and highlight the importance of assessing the momentum budget when interpreting ITCZ shifts.
Long‐term storage and transport length scale of fine sediment: Analysis of a mercury release into a river

Excessive suspended sediment concentrations create important water quality problems, but scientists disagree on how to predict its movement through watersheds. Most models assume that fine‐grained sediment moves rapidly far downstream, without recognizing the importance of episodic, long‐term storage. Here a historic industrial release of mercury is interpreted as a decadal sediment tracer experiment, releasing sediment particles “tagged” with mercury that are deposited on floodplains. As expected, floodplain mercury inventories decrease exponentially downstream, with a characteristic decay length of 10 km (95% confidence interval: 5–25 km) that defines the distance suspended particles typically move downstream before entering storage. Floodplain mercury inventories are not significantly different above and below three colonial age mill dams (present at the time of mercury release but now breached), suggesting that these results reflect ongoing processes. Suspended sediment routing models that neglect long‐term storage, and the watershed management plans based on them, may need revision.
Exercise and Pregnancy

&NA; Exercise is an important component of a healthy lifestyle and, as such, is recommended during pregnancy. However, the response to exercise of both the expectant mother and fetus varies depending on the fitness level of the woman. The response to exercise is also affected by the known musculoskeletal and physiologic changes associated with pregnancy, such as increased ligament laxity, weight gain, change in the center of gravity, and carpal tunnel syndrome. Although the physiologic responses of the pregnant woman and fetus have been well studied, the literature contains comparatively few studies investigating response to exercise. When performed properly, activities such as aerobics, impact and nonimpact activities, resistance training, and swimming may be beneficial during pregnancy.
Transport driven by eddy momentum fluxes in the Gulf Stream Extension region

The importance of the Gulf Stream Extension region in climate and seasonal prediction research is being increasingly recognised. Here we use satellite‐derived eddy momentum fluxes to drive a shallow water model for the North Atlantic Ocean that includes the realistic ocean bottom topography. The results show that the eddy momentum fluxes can drive significant transport, sufficient to explain the observed increase in transport of the Gulf Stream following its separation from the coast at Cape Hatteras, as well as the observed recirculation gyres. The model also captures recirculating gyres seen in the mean sea surface height field within the North Atlantic Current system east of the Grand Banks of Newfoundland, including a representation of the Mann Eddy.
Distinguishing between beach and dune sands

ABSTRACT The comparison of adjacent pairs of beach (largely foreshore) and dune sands from 74 localities of world-wide distribution has shown that it is generally possible to distinguish between the two, particularly if there are predominant onshore winds. The dune sands are usually rounder than the adjacent beach sands, have a larger silt content, and this silt has a higher content of heavy minerals. The beach foreshores, on the other hand, usually contain more shells and other calcareous organisms than the dunes. There is also some reason to believe that mica content is greater in beach foreshores than in adjacent dunes. The sand of beach berms appears to be intermediate in most respects between that of the foreshores and dunes. The areas where beaches and dunes are most difficult to distinguish are those where there are longshore, extremely variable, or offshore winds. In such localities it is thought that the dune sands are blown back onto the beaches causing intermixture and that in some cases the dunes are derived from sources other than from the adjacent beach. The best results in separating the two environments have come from beaches of the west coast of the United States and Baja California where onshore winds predominate. It is suggested that the chief reason for the differences between dune and beach sands is that the wind picks up from the beaches more of the rounder grains than of the flat and angular grains. There is no reason to believe that the grains are rounded appreciably by the wind in transit to the dunes. Nor does there appear to be any evidence from these comparisons that the dune grains become frosted. The greater quantity of heavy minerals in the dune silt fraction may be caused by removal by the wind of the light minerals.
The Rodney L. White Center for Financial Research Price Discovery in the U.S. Treasury Market: The Impact of Orderflow and Liquidity on the Yield Curve

We examine the role of price discovery in the U.S. Treasury market through the empirical relationship between orderflow, liquidity, and the yield curve. We find that orderflow imbalances (excess buying or selling pressure) can account for as much as 26 percent of the day-to-day variation in yields on days without major macroeconomic announcements. The effect of orderflow on yields is permanent and strongest when liquidity is low. All of the evidence points toward an important role of price discovery in understanding the behavior of the yield curve. ∗ We thank Alessandro Beber, Roger Edelen, Simon Gervais, Nick Souleles, Rob Stambaugh, Amir Yaron and seminar participants at the University of Pennsylvania for helpful comments. In addition, we thank Patricia Kelt of GovPX for explaining their data. Financial support from the Rodney L. White Center for Financial Research at the Wharton School is gratefully acknowledged. All remaining errors are our own. † Finance Department, The Wharton School, University of Pennsylvania, and NBER. Phone: (215) 898-3609. Email: brandtm@wharton.upenn. edu. ‡ Finance Department, The Wharton School, University of Pennsylvania. Phone: (215) 898-7543. Email: kavajecz@wharton.upenn. edu.
A climatology of tornadic activity over Greece based on historical records

In this study, the climatology of tornadoes, waterspouts and funnel clouds over Greece is presented for the period 1709–2012. The climatology consists of two datasets. An historical dataset (1709–1999) is based on newspaper archives, historical archives, published tornado literature, administrative records and reports of Hellenic National Meteorological Service (HNMS). A recent dataset (2000–2012) is based on newspaper articles, eyewitness reports to the media, HNMS's reports and an open‐ended online tornado report database which has been developed and maintained by the Laboratory of Climatology & Atmospheric Environment of the University of Athens. Altogether, 612 Greek tornadic events compose the climatology: 171 tornadoes, 374 waterspouts and 67 funnel clouds. Tornadic events during the past 13 years (2000–2012) have occurred all over the Greek territory and there is frequent tornadic occurrence over north Crete and Corfu Island. Tornadoes are more frequent to occur over NW Peloponnesus followed by south parts of Corfu Island. However, waterspouts are more frequent over north Crete followed by Corfu Island. Tornadic monthly variability depicts a maximum during October, followed by September and November. October is the month with the highest tornado frequency, followed by November and July. The highest waterspout frequency month is September followed by October and December. Tornadoes most commonly develop during the warm time of the day, as more than 75% of all cases occur during 08:00–15:00 hours UTC with a maximum at 12:00 hours UTC. Waterspout frequency of occurrence has two maxima during the day, the first early in the morning (07:00–09:00 hours UTC) and the second after the noon time period (14:00–15:00 hours UTC). The dominant (27.7% of total cases) intensity of tornadoes in Greece is T4 based on the T‐scale during the 300‐year period (1709–2012); there have been at least 114 injured and 29 deaths.