Miracle-dz/UniFAR-FTUs huggingface dataset:
Basin Evolution and Unconformity-Related Uranium Mineralization: The Camie River U Prospect, Paleoproterozoic Otish Basin, Quebec

The Paleoproterozoic Otish Basin, Quebec, hosts several uranium prospects that until recently remained underexplored and poorly understood. In this study, the Camie River U prospect, which shows similar charac teristics to high-grade unconformity-related U deposits, is the focus of an integrated basin analysis in the western Otish Basin. Conglomerate and sandstone of the Indicator Formation, which were deposited in at least six depositional sequences, were affected by insignificant early diagenetic compaction and cementation. This allowed the for mation of regional peak diagenetic aquifers, which became muscovite altered due to interaction with fluids having δ18 O and δ2H values similar to those of seawater-influenced basinal brines at 250°C. U mineralization at Camie River occurred at 1721 ±20 Ma based on a 207 Pb/ 206 Pb date obtained by laser ablation of uraninite, which coincides with a phase of the Otish Gabbro intrusion that has been dated at ca. 1730 Ma. The intrusive event promoted circulation of U-bearing basinal brines, triggering U mineralization at several locations in the western Otish Basin. Interaction of basinal brines with the Otish Gabbro produced coarse-grained chlorite, tourmaline, and phengitic muscovite, which decreased the fluid-conducting capabilities of diagenetic aquifers and resulted in fault zone- and fracture-dominated fluid flow. Subsequent fluid alteration events produced limited U remobilization, sulfides, sudoite, and siderite between ca. 1670 and 1410 Ma based on mineral paragenesis and 40 Ar/ 39 Ar dates of muscovite. Metamorphic fluids having high δ18 O values and temperatures around 300°C accompanied 1.2 to 1.0 Ga Grenville orogene sis and subgreenschist-grade metamorphism in the Otish Basin but were present at low water/rock ratios at Camie River and therefore produced little alteration. Post-Grenville uplift of the Otish Basin likely produced late, low-temperature alteration minerals that have been influenced by recent meteoric water, suggesting that the fault zones and fractures the minerals occupy remain as preferential fluid-flow pathways to the present day. Radiogenic Pb and the characteristic trace elements Mo + W + Nb have also preferentially dispersed from the mineralization along fault zones, fractures, and depositional sequence boundaries, and can be used to explore for Camie River-style U mineralization.
TP53 mutation and human papilloma virus status as independent prognostic factors in a Norwegian cohort of vulva squamous cell carcinoma

Vulva squamous cell carcinoma (VSCC) develops through two separate molecular pathways—one involving high‐risk human papilloma virus infection (HPV‐associated), and the other without HPV infection (HPV‐independent) often involving TP53 mutation. HPV‐associated VSCC generally has a better progression‐free survival than HPV‐independent VSCC. The aim of this study was to determine TP53 mutation status using immunohistochemistry, compare different methods of HPV detection and correlate both with survival in a retrospective cohort of 123 patients with VSCC.
Petrography and geochemistry of impactites and volcanic bedrock in the ICDP drill core D1c from Lake El'gygytgyn, NE Russia

The 3.6 Ma old and 18 km diameter El'gygytgyn impact structure in NE Siberia was drilled in 2008/09 by ICDP (International Continental Scientific Drilling Program). A 517 m long core hole (D1c) was drilled into the outer flank of the central uplift structure, with an overall core recovery of approximately 63%. Thereby, approximately 315 m lake sediments and approximately 202 m impactites were recovered. Here, we present a detailed petrographic and geochemical assessment of the impact breccia and bedrock sections in this core. The 97 m long lower bedrock unit (517–420 m below lake floor [blf]) consists of an ignimbrite. In the overlying upper bedrock unit (420–390 mblf), the core recovered a sequence of similar ignimbrite and several decimeters of mafic rocks. We interpret these units as rocks that are located close to their former, preimpact position, but have been somewhat rotated due to collapse of the central uplift (i.e., it represents parautochthonous basement). From about 390 to 328 mblf occurs a suevite package with an impact melt poor, clast‐dominated matrix, and lithic and mineral clasts that cover the entire range of volcanic target rocks known from the El'gygytgyn region. All stages of shock metamorphism (unshocked to melted) were observed in clasts, and in microclasts of the matrix, of suevite from different depths. Immediately below this package, at the contact to the underlying bedrock, occurs a 1 m wide sheared zone within vitrophyric ignimbrite, which we consider the actual crater floor. The uppermost approximately 12 m, from 328–316 mblf depth, seem to comprise reworked suevite, consisting of a mixture of sediments and suevite with more and, on average, stronger shocked minerals than found in the main suevite unit. This includes a small component of glassy spherules and impact melt fragments. Toward the top of this unit, lake sediments progressively become the dominant material in this section. We assume that this unit contains a fallback component from the ejecta plume that was mixed with the first sediments of the postimpact crater lake, and possibly some rocks that slumped off the inner crater wall—similar to a thin layer at the base of the sediment section of borehole LB‐5A recovered in Lake Bosumtwi (Ghana).
Geochemistry and age of two orthogneisses in the Proterozoic Mjøsa-Vänern ore district, southwestern Scandinavia

Abstract Two orthogneisses in the southwestern part of the Fennoscandian Shield have been investigated with respect to geochemistry, age and lead isotopic composition in feldspar. Both orthogneisses host gold-bearing quartz veins in the Mjøsa-Vänern ore district. The alkali-calcic Brustad augen gneiss of granitic composition is situated within the Mylonite Zone (MZ), close to Mjøsa in southeastern Norway. The calc-alkaline Harnäs gneiss of granodioritic composition is situated 50 km west of the MZ, northwest of Vänern in southwestern Sweden. U-Pb zircon dating yielded protolith ages of 1674±10 Ma for the Brustad augen gneiss and 1595+24 −17 Ma for the Harnäs gneiss, indicating affinity to the Transscandinavian Igneous Belt (TIB) and the Gothian Åmål granitoid suite, respectively; the extension of TIB units to the northwestern margin of the MZ is thus confirmed. Both rocks were deformed during Sveconorwegian orogenesis (c. 1.15–0.9 Ga). Their feldspar lead isotopic compositions are significantly more radiogenic than expected for initial lead and no vestiges of more primary lead could be detected in pre-deformational grains. Resetting of feldspar lead is suggested to have taken place at around 1000 Ma, in conjunction with Sveconorwegian ductile deformation. A revision of the domain boundaries within the Fennoscandian Shield is proposed, such that the Torsby and Borås Segments are conceptually excluded from the Southwest Scandinavian Domain. Thereby, the eastern boundary of the Southwest Scandinavian Domain is outlined by the MZ. It is further proposed that the Southwest Scandinavian Domain be renamed as the Gothian Domain.
Lightning Return-Stroke Current Waveforms Aloft, from Measured Field Change, Current, and Channel Geometry

[1] Three-dimensional reconstructions of six rocket-triggered lightning channels are derived from stereo photographs. These reconstructed channels are used to infer the behavior of the current in return strokes above the ground from current waveforms measured at the channel base and electric field change waveforms measured at a range of 5.2 km for 24 return strokes in these channels. Streak photographs of 14 of the same strokes are analyzed to determine the risetimes, propagation speeds, and amplitudes of relative light intensity for comparison with the electrical inferences. Results include the following: (1) The fine structure of the field change waveforms that were radiated by these subsequent return strokes can be explained, in large part, by channel geometry. (2) The average 10–90% risetime of the stroke current increased by about a factor of seven in our sample, from an observed 0.31 ± 0.17 μs at the surface to an inferred 2.2 ± 0.5 μs at 1 km path length above the surface. (3) The three-dimensional propagation speed of the current front averaged 1.80 ± 0.24 × 108 m/s over channel lengths typically greater than 1 km. (4) Assuming that the measured current was entirely due to the return stroke forced an unreasonably large and abrupt reduction in inferred current amplitude over the first few tens of meters above the surface, especially in cases when the leader was bright relative to its stroke. Therefore a significant fraction of the current at the surface was probably due to the leader in such cases. (5) Independent of the above, peak return stroke currents decreased by approximately 37 ± 12% between 100 m and 1 km of path length above the surface. Because of uncertainty about how to partition the measured current between leader and return stroke, however, we are unable to infer the variation of current amplitude near the ground.
Associations between central pulse pressure, microvascular endothelial function, and fluid overload in peritoneal dialysis patients

ABSTRACT Background Microcirculatory endothelial dysfunction is a complex phenomenon that contributes to the development of cardiovascular disease. However, the relationship between microcirculatory endothelial dysfunction and macrovascular disease remains incompletely understood. Fluid overload is a risk factor for cardiovascular mortality in patients undergoing peritoneal dialysis. Therefore, we investigated the effects of chronic fluid overload on both the microcirculation and macrocirculation in these patients. Methods Thirty patients undergoing peritoneal dialysis were included in this cross-sectional study. We measured their central blood pressure and pulse wave velocity, assessed their microvascular endothelial function using drug-induced iontophoresis with laser Doppler flowmetry, and determined the amount of fluid overload using bioimpedance. We conducted a Spearman correlation analysis, univariate analysis, and stepwise multivariate regression models to determine the associations among the hemodynamic parameters. Results Acetylcholine-induced iontophoresis with laser Doppler flowmetry showed a correlation with both brachial and central pulse pressure (PP), but not with pulse wave velocity. Fluid overload was associated with both central and brachial PP and remained an independent predictor of central PP even after adjusting for multiple factors. However, fluid overload was not associated with microcirculatory endothelial function. Conclusion In peritoneal dialysis patients, we observed a significant association between central PP and microvascular endothelial function, indicating a connection between macrocirculation and microcirculation. However, conclusive evidence regarding fluid overload as a mediator between these circulatory systems is lacking. Further research is needed to investigate this relationship.
Sr isotope geochemistry and hydrothermal alteration of the Oman ophiolite

The Sr isotopic behavior in hydrothermally altered rocks of a complete section through the Wadi Fizh oceanic crust in the Oman ophiolite was investigated in order to evaluate seawater-rock interaction through the oceanic crust. On the basis of rock-types, secondary mineral assemblage, alteration temperature, average 87Sr/86Sr of hydrothermal fluids, and degree of alteration, the section is divided into the following 5 sequences: (1) mainly basalts and clay minerals, low alteration temperature, average 87Sr/86Sr 0.70634, and 78% degree of alteration; (2) mainly basalts and chlorite, clay minerals and calcite, fairly low alteration temperature, average 87Sr/86Sr 0.70584, and 76% degree of alteration; (3) basalts and sheeted dike diabase and prehnite-actinolite facies, moderate alteration temperature, average 87Sr/86Sr 0.70519, and 85% degree of alteration; (4) dike diabase, plagiogranite, metagabbro and epidosite and prehnite-free greenschist facies, high alteration temperature, average 87Sr/86Sr 0.70514, and 65% degree of alteration; and (5) noncumulate and cumulate gabbro and amphibolite facies, very high alteration temperature, average 87Sr/86Sr 0.70413, and 85% degree of alteration. Alteration (metamorphic) grade deduced from secondary mineral assemblages generally increases versus stratigraphic depth. Only 15% of the rocks have escaped hydrothermal alteration. The estimated strontium isotopic compositions of hydrothermal fluids are much more water-dominated than those reported previously from modern and ophiolitic hydrothermal systems. On the basis of ideal model analysis we conclude that the whole sequence of oceanic crust in the Wadi Fizh section has experienced seawater recharge (downflow zone). The evidence suggests that the Wadi Fizh section was located close to a segment boundary of the oceanic crust along a spreading axis.
Minimum iron requirements of marine phytoplankton and the implications for the biogeochemical control of new production

The Fe : PO. , ratio at which nutrient limitation of final cell yield shifts from one nutrient to the other was determined for 22 species of marine phytoplankton. Among eucaryotic phytoplankton, coastal species have subsistence optimum Fe: P molar ratios of lo-* to 10-3.1, but most oceanic species have ratios of < 1 O--4, indicating that oceanic species have been able to adapt their biochemical composition to the low availability of Fe in the open ocean. In contrast, both coastal and oceanic species of cyanobacteria have relatively high Fe : P molar ratio requirements, ranging from 1O-1.4 to 1O-2.7. A simple comparison of these requirement ratios with the ratios of the Fe and PO, fluxes to the photic zone from deep water and the atmosphere indicates that new production of cyanobacterial biomass is Fe limited, but new production of eucaryotic algal biomass is not. Because of the large differences among species in their Fe requirements, especially between procaryotes and eucaryotes, changes in the relative inputs of Fe and PO, to the photic zone are expected to lead to changes in the species composition of phytoplankton communities. Indeed, the ratio of atmospheric to deep-water inputs of nutrients and the resulting Fe : P input ratios appear to influence the relative abundance of unicellular cyanobacteria and Trichodesmium and their vertical and biogeographic distributions. Because some phytoplanlcton species have adaptations that reduce their dependence on combined N and Fe but not on P, it is concluded that PO, is the ultimate limiting nutrient of new production of organic C on a geochemical and evolutionary time scale, even though N and Fe are important growth rate-limiling nutrients on an ecological time scale. What controls the rate of new production of organic C in the ocean is of great interest because of its influence on atmospheric 0, and C02, sedimentation and organic burial, and fisheries. One of the first to consider the geochemical control of new production in the ocean, Redfield (195 8) conducted a gedanken experiment in which he compared the ratio of NO3 to PO, in deep water with the ratio of N to P in marine biota and asked which nutrient would be depleted first by the biota if the deep water was upwelled into the photic zone. At that time,, trace metals were not generally considered as important limiting nutrients because of the high concentrations observed in the ocean as a result of inadequate techniques and serious contamination problems. As a result of greatly improved techniques, we now know that many trace metals are present in the ocean
Automated rangeland vegetation cover and density estimation using ground digital images and a spectral-contextual classifier

A method to estimate vegetation cover, density and background brightness parameters in a rangeland environment from low-altitude digital images is presented. A digital still-frame camera, mounted on a 5.2 m pole, is used to acquire images of the ground. The acquired images are then processed using an unsupervised spectral-contextual classifier to extract quantitative measurements automatically. The test results show that the extracted cover measures from the fully automated procedure provide an accuracy of 0.89 to 0.99, measured in kappa, compared with 0.36 to 0.58 and 0.79 to 0.95 from k -means clustering and maximum likelihood supervised classifications respectively. For the clump density measure, the proposed method had an error level ranging from 0 to -62%-hundreds of times less than those produced from both k -means and maximum likelihood classifications. The presented method overcomes human subjectivity inherent in other commonly used ground investigation methods for estimating vegetation cover. The results provide an accurate and objective reference for the calibration of models which relate the spectral reflectance recorded by remote sensors to quantitative measures of range condition.
SUBLETHAL NARCOTIC IMPACTS OF DIETARY POLYCYCLIC AROMATIC HYDROCARBONS ON THE BIOENERGETICS OF AND POLYCHLORINATED BIPHENYL (PCB) BIOACCUMULATION IN FUNDULUS HETEROCLITUS

Title of Dissertation: SUBLETHAL NARCOTIC IMPACTS OF DIETARY POLYCYCLIC AROMATIC HYDROCARBONS ON THE BIOENERGETICS OF AND POLYCHLORINATED BIPHENYL (PCB) BIOACCUMULATION IN FUNDULUS HETEROCLITUS Amy A. Merten, Doctor of Philosophy, 2005 Dissertation Directed By: Professor Robert P. Mason University of Maryland, Chesapeake Biological Laboratory Accumulation of non-polar narcotic chemicals in organisms alters their metabolic rates and therefore, their energetic demands. It is hypothesized that decreases in standard metabolic rate from accumulation of narcotics reduces feeding. Thus, exposure to and accumulation of narcotics may cause a negative feedback, reducing net bioaccumulation. Three experiments were conducted to examine the consequences of narcotic exposure on the bioenergetics and bioaccumulation rates of Fundulus heteroclitus continuously challenged with sublethal levels of hydrophobic organic chemicals (HOCs). In the final experiment (120 days), fish were exposed to two concentrations of a model narcotic, 3-aminobenzoic acid ester methanesulfonate (MS-222) (0 and 50 mg/L), and four concentrations of PAH-contaminated food treatments sampled over five time points. All food treatments contained background concentrations of polychlorinated biphenyl (PCB) congeners (40 ng/g Σ-PCBs w/w) and were used as a tracer of bioaccumulation. No statistically significant differences in weight, length, or condition factors among treatments, except on day 120 where MS-222 exposed fish were longer than non-MS-222 exposed fish (p = 0.015). Standard metabolic rate responded in a non-linear manner. At low PAH doses (835 ng/g Σ-PAH), SMR decreased significantly (p = 0.093, α = 0.10). Fish fed 100% PAH-contaminated food (regardless of MS-222), had significantly elevated SMRs (p = 0.02). MS-222 did not affect PCB accumulation. PAH-contaminated food enhanced PCB accumulation measured in fish. There was an overall interaction between the food treatment and aqueous MS-222 exposures (p = 0.004). The results indicate that total chemical burden from the MS-222 plus PAH-contaminated food exposures masked the sublethal narcotic effect of MS-222, and produced a net increase in the standard metabolic rates of Fundulus heteroclitus, perhaps because of increased energetic costs associated with detoxification and bioactiviation processes. The results of the experiments were subtle and non-linear with respect to dose of PAH-contaminated food. To explore whether small changes in SMR (± 5 – 10 %) may be important costs, a bioenergetics model was developed. The model tracks biomass (daily age classes) based on a balance of weight-specific consumption and bioenergetic costs (respiration, growth, and mortality). The model projects population biomass as the main output for comparing different “impacts. ” SUBLETHAL NARCOTIC IMPACTS OF DIETARY POLYCYCLIC AROMATIC HYDROCARBONS ON THE BIOENERGETICS OF AND POLYCHLORINATED BIPHENYL (PCB) BIOACCUMULATION IN FUNDULUS HETEROCLITUS
Geothermometry and geobarometry of Dalradian metapelites and metabasites from the Central Scottish Highlands

Synopsis Temperatures and pressures of metamorphism have been estimated for a suite of Dalradian garnetiferous mica schists, calcareous pelites, and hornblende schists (‘Green Beds’) from Central Perthshire. Garnet-biotite, calcite-dolomite, and muscovite-paragonite geothermometers indicate temperatures ranging from about 500°C, corresponding to the lowest grade, to a maximum of about 580°C, corresponding to the highest grade. Garnet-kyanite-plagioclase-quartz, and epidote-plagioclase-garnet-quartz equilibria indicate pressures of 8–11 kb. These temperature, pressure estimates agree well with the experimentally determined phase stabilities. A thermal gradient of 60–65°C/kb (20–22°C/km geothermal gradient) characterizes this area.
Small‐scale experimental simulation of talus evolution

We investigated a small‐scale laboratory model of a talus slope evolution. Five different size classes of basaltic rock were selected and marked with different colours. Homogenized mixtures of grains of different sizes were dropped from a fixed height onto a tilted experimental board covered with a loose granular layer. This was conducted in a series of regular sequences, and the resulting distribution on the board was studied after each sequence. At the beginning of the experiment, the grains developed a longitudinal gradation similar to natural talus slopes, where small grains settle at the top while the large ones roll down to the distal part. However, after a transient period dominated by single‐particle dynamics on the inert granular medium, the evolution proved to be more variable than expected. Due to the continuous shower of falling grains, the shear stress at the bottom of the upper granular layer increased. This resulted initially in a slow creep down slope that finally collapsed in large avalanches homogenizing the material. The slides occurred at the boundary between a weaker layer created by migration of small grains through the interstices, and marked by a vertical transition between small and large grains. We compare the experimental findings with observations from natural talus slopes, and suggest that similar experiments may be helpful in understanding the evolution of taluses. Copyright © 2009 John Wiley & Sons, Ltd.