Miracle-dz/UniFAR-FTUs huggingface dataset:
Coastal upwelling and a history of organic-rich mudstone deposition off Peru

Summary The present-day upwelling circulation off Peru, the regional pattern of organic matter in surface sediments and the stable carbon isotope characteristics of Neogene and Quaternary carbonate lithologies suggest a unique feedback mechanism in continental margin deposition and subsequent alteration after burial. In such a scenario, the high bioproductivity, the position of a poleward flowing undercurrent and the rate of subsidence of margin basins appear to be the principal variables controlling this mechanism. Transfer of organic matter from the sea surface to the sea floor is particularly efficient in the upwelling ecosystem off Peru. Preservation and burial are enhanced by high bulk sedimentation rates along the upper continental slope (between 11°–15°S) at depths where the subsurface current velocities decrease below those normally associated with the poleward flow. Burial and preservation are diminished, however, where shallow water depths promote continuous reworking of the bottom sediments by onshore flows and alongshore water movement (between 6°–10°S). The resulting sedimentary facies are distinctly different from each other in that the former process yields an organic-rich (> 5 wt % Corg) and the latter process yields a calcareous (> 15 wt % CaCo3) mud facies. The bulk sediment accumulation and individual component fluxes are estimated for both portions of the margin situated between 6° and 15°S latitude and lying in < 500 m of water depth. Furthermore, the chemical environment of organic-matter decomposition in the rapidly accumulating carbonate-poor facies is dominated by microbial fermentation and methanogenesis, whereas, the muds containing lesser amounts of organic matter are dominated by microbial sulphate reduction. These differences in facies composition persist throughout the subsequent stages of compaction and diagenesis. Most prominent among these is the formation of ‘organic’ dolomites with distinctly different isotopic signatures and mineral assemblages. The original upwelling facies (i.e., organic-rich muds or calcareous muds), the extent of reworking by subsurface currents, and the subsidence history of the margin basins may be inferred from these sedimentary signatures.
Lower Jurassic epicontinental carbonates and mudstones from England and Wales: chemostratigraphic signals and the early Toarcian anoxic event

Sections through Lower Jurassic epicontinental carbonates from Southern Britain (Junction Bed and equivalent) show a positive carbon‐isotope excursion (δ13Ccarbonate), detectable in bulk rock, in the falciferum Zone of the lower Toarcian. Isotopic data from organic matter in more clay‐rich sections from Wales and north‐east England, together with determinations on belemnite calcite, indicate that highest δ13C values are localized in the upper exaratum Subzone of the falciferum Zone. Levels of particular enrichment in organic carbon were developed in the early to mid‐exaratum Subzone and hence pre‐date this δ13C maximum. These phenomena reflect the impact of the early Toarcian oceanic anoxic event in the British area. Similar isotopic trends have been recorded in other Toarcian sections from Tethyan Europe and are interpreted as reflecting the chemistry of sea water. On the assumption of isotopic correlation between the English and Tethyan sections, the δ13C maximum would be everywhere dated as latest exaratum Subzone in terms of the north European ammonite scheme.
The Roles of Fractional Crystallization, Magma Mixing, Crystal Mush Remobilization and Volatile–Melt Interactions in the Genesis of a Young Basalt–Peralkaline Rhyolite Suite, the Greater Olkaria Volcanic Complex, Kenya Rift Valley

The Greater Olkaria Volcanic Complex is a young ( 20 ka) multi-centred lava and dome field dominated by the eruption of peralkaline rhyolites. Basaltic and trachytic magmas have been erupted peripherally to the complex and also form, with mugearites and benmoreites, an extensive suite of magmatic inclusions in the rhyolites. The eruptive rocks commonly represent mixed magmas and the magmatic inclusions are themselves two-, three- or four-component mixes. All rock types may carry xenocrysts of alkali feldspar, and less commonly plagioclase, derived from magma mixing and by remobilization of crystal mushes and/or plutonic rocks. Xenoliths in the range gabbro–syenite are common in the lavas and magmatic inclusions, the more salic varieties sometimes containing silicic glass representing partial melts and ranging in composition from anorthite ± corundum- to acmite-normative. The peralkaline varieties are broadly similar, in major element terms, to the eruptive peralkaline rhyolites. The basalt–trachyte suite formed by a combination of fractional crystallization, magma mixing and resorption of earlier-formed crystals. Matrix glass in metaluminous trachytes has a peralkaline rhyolitic composition, indicating that the eruptive rhyolites may have formed by fractional crystallization of trachyte. Anomalous trace element enrichments (e.g. 2000 ppm Y in a benmoreite) and negative Ce anomalies may have resulted from various Na- and K-enriched fluids evolving from melts of intermediate composition and either being lost from the system or enriched in other parts of the reservoirs. A small group of nepheline-normative, usually peralkaline, magmatic inclusions was formed by fluid transfer between peralkaline rhyolitic and benmoreitic magmas. The plumbing system of the complex consists of several independent reservoirs and conduits, repeatedly recharged by batches of mafic magma, with ubiquitous magma mixing.
Use of remote sensing for drought stress monitoring, yield prediction and varietal evaluation in castor beans (Ricinus communis L.)

The current study was taken up to investigate the utility of remote sensing tools like infrared thermometer and spectral radiometer for screening of germplasm, stress monitoring and yield prediction in castor beans (Ricinus communis L.). The study was carried out through field experiments conducted for six years (1994–1999) at Hayatnagar Research Farm, Hyderabad, India. In each year, four cultivars of castor beans, viz. VP‐1, 48‐1, GCH‐4 and Aruna, were planted on two different dates maintaining an interval of 6–8 weeks so as to expose the crop to different environments. The infrared thermometric observations like canopy–air temperature differential (T c–T a) explained 50–60% variation in soil moisture status and showed a significant relationship with soil moisture. Yield of castor beans exhibited significant inverse relationship with T c–T a, which explained 59% of variation in yield. The hybrid GCH‐4, registering comparatively lesser mean T c–T a over the entire growing period, established itself as a better cultivar. The spectrometer observations also proved GCH‐4 to be a superior genotype in view of its higher reflectance in near‐infrared region of the spectrum. The significant negative relationship of T c–T a of GCH‐4 with saturation vapour pressure deficit brought out its drought tolerance trait over the other genotypes studied. These findings at field level can be extended to wider spatial level using satellite imageries.
Early Archean crust of the Middle Dnepr and Azov domains, Ukrainian Shield—evidence from ages of detrital zircons in Mesoarchean greenstone belts

To clarify the early evolution of the Ukrainian Shield we have dated detrital zircons, separated from metasedimentary rocks of Mesoarchean greenstone belts from the Middle Dnepr and Azov domains (Ukrainian Shield). For the Middle Dnepr domain, the main population of analyzed zircons from three samples of metasediments from the upper Belozerka series of the Verkhovtsevo and Belozerka greenstone belts is in the age range 3.0 to 3.1 Ga, with some crystals as old as 3.2 to 3.3 Ga. The results indicate that the sediment sources were dominated by volcano-plutonic rocks of the belts themselves, with some contribution from basement rocks of the Auli series. For the Azov domain, zircons from four samples of mica schists from the Soroki greenstone belt were analyzed, focusing mainly on cores identified by CL and inner parts of crystals. The data show a group of ages in the range 3.5 to 3.6 Ga. Several zircon cores are older than 3.7 Ga. Overgrowths clearly identified by CL are about 3.2 to 3.0 Ga old. Trace element compositions of the studied metasedimentary rocks (fractionated REE patterns, low HREE contents and negative Nb anomalies) reflect contributions from TTG magmatic series and related volcanic rocks to the sediments, and input from ultramafic-mafic sources is identified using Cr/V and Ni/Co ratios. Sm-Nd model ages of 3.1 to 3.3 and 3.3 to 3.4 Ga for the Middle Dnepr and Azov domains, respectively, and εNd(T) for the analyzed samples, are in a good agreement with the zircon data. Our new results indicate that Paleoarchean crust in the Azov domain was more widely distributed than previously recognized.
Distribution of macrobenthic taxa across the Scotia Arc, Southern Ocean

Abstract An extremely dynamic chain of archipelagos links South America and the Antarctic Peninsula. It includes islands, which are large and small, old and young, near continental margins and isolated, and well sampled and poorly known. The current study sampled the macrobenthos of all the major archipelagos of this arc at shelf and slope depths using an Agassiz trawl. At least four samples (200 m, 500 m, 1000 m and 1500 m) were taken down-slope at Falkland Trough, Shag Rocks, South Georgia, South Thule, Powell Basin, Elephant Island, and Livingston Island sites and one sample was collected in the caldera of Deception Island. Despite the biogeographical and biodiversity importance of this region, this is the first time (by definition) entire standardized trawl samples have been analysed from all its archipelagos and at any consistent taxonomic level. We found 15 phyla and 29 classes of macro- and megafauna in total across the samples, many of which occurred at all sites. Even at remote and geologically young sites richness was high. Richness increased with abundance and wet mass and was highest in the shallow shelf samples and lowest at 1500 m. Abundance and wet mass varied more than two orders of magnitude, even within classes or study areas. There were strong similarities between the ascidian dominated shallow faunas of the two active volcanic sites, Southern Thule and Deception Island despite huge differences in isolation. There were also strong faunal similarities between Falkland Trough and Shag Rocks despite being on opposing sides of the Polar Front. In contrast two near neighbours with similarly soft substrata, Elephant and Livingston islands were amongst the most dissimilar.
Glacial geomorphology of the Dalijia Shan region, northeastern Tibetan Plateau

A glacial geomorphological map of the Dalijia Shan (Shan = mountain) region in the most northeastern part of the Tibetan Plateau is presented here. The map covers an area of approximately 10,730 km2 at a scale of 1:600,000. A combination of remote sensing imagery is used to identify glacial landforms within the study area including: Shuttle Radar Topography Mission (SRTM) digital elevation models (DEMs; 90 m), Advanced Spaceborne Thermal Emission and Reflection Radar (ASTER) DEMs (30 m), Landsat 7 ETM+ satellite imagery, and Google Earth™ imagery. Two types of glacial landforms are identified and mapped: glacial valleys (including cirques in some cases) and marginal moraines. These landforms comprise approximately 1.3% of the study area, indicating more restricted past glaciation than in previously mapped areas in the central and eastern Tibetan Plateau. Glacial landforms are limited primarily to the mountainous region of the study area, largely around Dalijia Peak, lending support to a hypothesis of limited glacier and ice cap expansions in this region.
Modeling the ionospheric response to traveling atmospheric disturbances

Anomalous increases of the ionization density at middle latitudes (positive ionospheric storms) are often a prominent feature of upper atmospheric storms. One of their possible causes are traveling atmospheric disturbances (TADs) which propagate from polar to equatorial latitudes, carrying along equatorward-directed meridional winds. At middle latitudes, these winds cause an increase in the height of the F2 layer which in turn will lead to an enhancement of the ionization density. Using a simple description of a TAD and an ionospheric model, we are able to reproduce the basic properties of such perturbations. We also attempt to simulate an actually observed storm period. Rough agreement is obtained when the wind speed is derived from the height of the F2-layer peak. A more detailed simulation of the initial phase of the storm requires a more refined TAD model with time-dependent height gradients in the wind field.
Letter: The Risk of Bladder Cancer in Korean Diabetic Subjects Treated with Pioglitazone (Diabetes Metab J 2012;36:371-8)

Dear Editor, Ever since prospective pioglitazone clinical trial in macrovascular events (PROactive), the very first large randomized trial of pioglitazone, published in 2005 [1], whether this antihyperglycemic agent could increase the risk of bladder cancer was debated by diabetologists and pharmacologists. Despite lack of support from molecular mechanism, several cohorts observed the association between long term application of pioglitazone and the bladder cancer risk [2,3]. Recently, a nested case-control study provided by Azoulay et al. [4] also indicated bladder cancer risk increased 1-fold after 2-year usage of pioglitazone. It appeared no doubt that bladder cancer should be caused by this agent. However, no rational explanation was given by investigators. In the current study by Song et al. [5], an obviously lower prescription of pioglitazone was reported in diabetic patients with bladder cancer compared with those bladder cancer-free ones (6.4% vs. 15%). Interestingly, the adjusted odds ratio (OR) of bladder cancer incidence was 2.09, which was almost the same with previous reports [1-4], despite failed to reach statistical significance in the current population. This result brought us two questions: Why was the prescription of pioglitazone in diabetic patients with bladder cancer so low compared with controls? What made the result of such difference between the results from univariate and multivariate statistics? As the risk of pioglitazone has been reported for years since 2005 [1], diabetologists all over the world may have already noticed the risk of this agent, and have a mind to prevent the usage in real clinical practice if a patient has a high risk of cancer. Furthermore, a potential selective bias could be hardly prevented in the design of matched case-control study. For the second question, it appears that the multivariate model in the study perfectly adjusted for all potential confounding biases, and the adjusted OR just gave the 'true' risk like previous studies. Among the adjusted factors, co-existing neoplasm would a potential bias, and the reason was mentioned above. However, it required further analysis of the original data to determine whether it is really the very one that explained such difference between the results from univariate and multivariate statistics. It could be of interest that might tell us why there was little prescription of diabetic patients with bladder cancer, and help us understand if it is really pioglitazone which lead to the cancer of urinary bladder.
Ionospheric storm effects at subauroral latitudes: A case study

An attempt is made to classify ionospheric storm effects at subauroral latitudes according to their presumed origin. The storm of December 7/8, 1982, serves as an example. It is investigated using ionosonde, electron content, and DE 2 satellite data. The following effects are distinguished: (1) positive storm effects caused by traveling atmospheric disturbances, (2) positive storm effects caused by changes in the large-scale thermospheric wind circulation, (3) positive storm effects caused by the expansion of the polar ionization enhancement, (4) negative storm effects caused by perturbations of the neutral gas composition, and (5) negative storm effects caused by the equatorward displacement of the trough region.
Diagnosing a meander of the shelf break current in the Middle Atlantic Bight

Two wintertime hydrographic crossings of the shelf break current in the Middle Atlantic Bight are analyzed. Separated by 3 days, the two sections sampled opposite phases of a meander of the current. The shipboard acoustic Doppler current profiler (ADCP) data reveal a strong, convergent jet during the first crossing, transporting 0.32 Sv of water equatorward. During the second crossing the transport is the same but the jet is weak and divergent. The measured Rossby numbers imply that the jet is significantly nonlinear in the convergent state. The associated potential vorticity Q distributions differ substantially; the core of the weak jet is characterized by a region of uniform Q, whereas the strong jet contains no such feature. Surface thermal imagery indicates that the leading edge of a steep meander trough was sampled during the first crossing, followed by a broad crest during the second crossing. This is consistent with the convergent versus divergent nature of the flow in the two sections. A nearby Gulf Stream ring likely caused the steepening of the trough. After integrating the spatially low-passed thermal wind shear, the resulting geostrophic sections are compared to the similarly low- passed ADCP fields. This, together with the scales of the meander deduced from the surface imagery, indicates that the trough was in gradient wind balance, whereas the crest was predominantly geostrophic. These observations are consistent with the structure and dynamics of modeled baroclinic jets.
Towards a sustainable use of water resources: a whole-ecosystem approach using network analysis

The object of this paper is to investigate the sustainability of water use in human settlements. The water system of a small municipality in northern Italy is discussed as a case study. By measuring water exchanges between different sectors of activity within the municipal borders, and considering underground and surface waters as natural components of this system, a network of flows is built and successively investigated by network analysis, a tool that is comprised in the apparatus of ecosystem ecology. By calculating the reciprocal dependence of compartments, the amount of resource that is involved in cycling, the length of exchange pathways, and the organisation of flows, network analysis shows that the system does not use water in a sustainable manner and provides general criteria for improving sustainability. In this respect, options to improve sustainability are also discussed. The results of this study support the idea that the ecosystem approach can provide an interesting conceptual perspective in which sustainability issues can be framed, and that network analysis is a promising tool to handle these issues in practice.
Simultaneous optical observations of transpolar arcs in the two polar caps

Optical observations with DE 1 and Viking demonstrate conclusively that transpolar arcs can be present simultaneously at polar latitudes in both hemispheres. The arcs observed here are aligned parallel to one another on opposite sides of the magnetic pole, and relative to the noon-midnight meridian are rotated slightly in the counterclockwise direction when viewed from above the North Pole.
An elastoplastic damage model for semi-brittle rocks

A new elastoplastic damage model, based on experimental evidences and using a thermodynamic framework, is proposed for rock materials under a large range of stresses. The elastic and plastic properties are affected by induced damage, which leads to material softening behaviour. After formulation of the model and determination of its parameters, triaxial compression tests on sandstone are simulated to show the model's consistency. In order to describe progressive failure process due to onset of strain localization, the elastoplastic model is extended by including a non-local damage formulation. Three representative cases are studied. The numerical results verify the well-known fact that the elastoplastic non-local damage model avoids spurious mesh sensitivity and provides a reliable description of the growth of the damage zone and the failure process.
Chiniquodontid cynodonts: systematic and morphometric considerations

Systematic and morphometric reappraisal of most specimens previously assigned to the cynodont clade Chiniquodontidae reveal that the group is diagnosed by two autapomorphies: (1) the distinctive angulation between the posterior portion of the maxillary and the anterior portion of the zygomatic arch and (2) very extended pterygoid flanges, ending in a thin projection; and a combination of features including: posterior postcanines sectorial with principal cusps backwardly recurved, and a long osseous palate. The species Chiniquodon theotonicus (including Belesodon magnificus, Probelesodon kitchingi, P. lewisi and P. minor) and C. sanjuanensis (comb. nov.) were the only recognised members of the family on the basis of qualitative characters. The South American species Cromptodon mamiferoides, Probainognathus jenseni and Thrinaxodon brasiliensis are thus excluded from the group, as are the African taxa Aleodon brachyrhamphus and Cistecynodon parvus. Allometric analysis of chiniquodontids sensu stricto reveals that: (1) all specimens can be confidently arranged in a single growth series, irrespective of their original species assignments; and (2) most of the measurements change isometrically with respect to skull length. Adults are virtually scaled–up juveniles, showing a deepened zygoma, a longer osseous palate, and a wider anterior muzzle in the canine region. Thus, allometric data reinforce the proposed synonymy of all forms, with the specific status of C. sanjuanensis supported by qualitative diagnostic traits.
Comparison of the microfracture localization in granite between fracturation and slip of a preexisting macroscopic healed joint by acoustic emission measurements

Experiments of fracturation and slip of a preexisting macroscopic healed joint have been performed under triaxial deformation on granite from Mayet de Montagne (France). This granite shows high grain-scale inhomogeneity. Acoustic emissions have been recorded and hypocenters have been determined during the entire experiments. For both rupture experiment and slip experiment, precursory localization of microfractures in the final rupture plane has been observed in the early stage of deformation, well before the dilatancy. It is likely that not only initial closure of favorably oriented cracks but also breaking of partially cemented grains or slipping between grains may occur in the pseudoelastic phase and are already localized on the final rupture plane where the shear stress seems to be concentrate. This behavior is observed in both cases where stress heterogeneity and rupture nucleation are controlled by (1) medium-scale heterogeneity at the grain scale (HS sample) or (2) macroscopic heterogeneity in the form of a preexisting healed joint (JS sample). The sample with the healed joint exhibited ~ 1.6 times more acoustic emission events than the intact sample. The presence of the healed joint significantly weakened the sample.
Shear Deformation of Locked Sand in Triaxial Compression

Dense, uncemented, locked Athabasca oil sand specimens were tested in drained triaxial compression with enlarged lubricated platen ends. Computer tomography and scanning electron microscopy (SEM) imaging techniques were used to examine the micro-structural features of the intact and sheared specimens. The micro-structures studied in this paper include shear banding pattern, shear band thickness, and spatial porosity distributions inside and outside shear bands.