gebhart/patrepeval huggingface dataset:
Stimulation of High Temperature Carbonate Reservoirs Using Seawater and GLDA Chelating Agents: Reaction Kinetics Comparative Study (2017)

Abstract Hydrochloric acid (HCl) as a stimulation fluid of deep oil and gas carbonate reservoirs is very common practice in the industry. Using HCl acid during matrix acid treatment in carbonate acidizing has the limitations of; rapid tubulars corrosion, formation face dissolution due to fast uncontrolled reaction rate especially at high temperature reservoirs and low injection rates, and induced formation damage due to sludge formation in presence of crude oil with high asphaltene content. There is also a difficulty of using HCl in stimulating multilateral and horizontal wells due to its fast reaction with the reservoir rock. With the intensive care given to the environment in the 21 century, chelating agents were introduced as alternatives to HCl to alleviate the problems associated with HCl. GLDA (Glutamic acid diacetic acid) chelating agent was used previously to stimulate carbonate reservoirs at high pressure and high temperature (HPHT) conditions. GLDA was prepared in fresh water to stimulate these reservoirs. In this paper, the effect of dilution using seawater on the reaction kinetics of low pH GLDA (3.8 pH) with different carbonate rocks under HPHT conditions was investigated using the rotating disk apparatus (RDA). The reaction experiments of GLDA solution with carbonate rocks in both fresh (GLDA/DI) and seawater (GLDA/SW) were carried out at the same conditions. Indiana limestone and Austin chalk carbonate rock samples were used to investigate the effect of rock facie on the reaction. The reaction regime of GLDA chelating agent with calcite is identified to be mass transfer limited in both seawater and fresh water. Also the overall reaction rate and calculated diffusion coefficient showed a high dependency in the temperature. At 200°F and 1000 psi the diffusion coefficient calculated for the reaction of GLDA/SW with Austin chalk is an order of magnitude higher than the reaction of the same fluid with Indian limestone. The reported diffusion coefficients can be used to simulate for the optimum injection rate required for stimulating high temperature carbonate formation. Highlighting the effect of porosity facies in the acid reaction with carbonate rock will lead to better understanding of the overall reaction of stimulation fluids with carbonate rocks of the same lithology but different porosity facies.
A new reconfigurable mixerless polar transmitter for multi-standard and SDR applications (2016)

A mixerless polar transmitter architecture using an analog RF variable gain amplifier (VGA) and an analog phase shifter is proposed and implemented. This architecture avoids the use of nonlinear switching mixers and quadrature modulator circuits for frequency up-conversion. Thus, spurs and distortion common to mixer circuits are absent and therefore the proposed architecture does not require any filtering at its RF output. Hence, the proposed topology can be implemented for wider RF bandwidths and is more reconfigurable for multi-standard and Software Defined Radio applications. The unusual nonlinear behavior of the proposed polar transmitter was analyzed and mitigated using a new modified memory polynomial model. The proposed architecture achieved an EVM of 0.92 % for an LTE signal of 1.4 MHz bandwidth with 64 QAM constellation.
Phonon-mediated detection of particles (1989)

Over the past five years particle physicists, nuclear physicists and astrophysicists have been increasingly interested in using phonons to detect particle interactions. In these detection attempts it is obviously critical to integrate the understanding that the phonon physicists have accumulated on the mechanisms governing the production, propagation and detection of those phonons. Vice versa, some of the issues raised by the particle detection problem may be of significant interest and the high sensitivity methods being developed may become important for phonon physics investigations. These were the motivations for a round table discussion between members of the two communities. This report attempts to summarize the themes of a very interesting discussion. 24 refs., 2 figs., 1 tab.
iodide. A synthetic approach to olguine: further model studies (1987)

SERAFIN VALVERDE, BERNARW HERRADON, ROSA M. RABANAL, and MANUEL MARTIN-LOMAS. Can. J . Chem. 65, 332 (1987). The enantiomerically pure title compound ((4R,5S)-(5-methyl-2,2-dimethyl-l,3-dioxolane-4-ylmethyl)-phosphonium iodide) has been synthesized starting from (R,R)-(+)-tartaric acid. The synthesis of an olguine analog has been carried out. Attempts have been made to improve the stereoselectivity and yield of key steps.
Molecular dynamics simulations of clusters and thin film growth in the context of plasma sputtering deposition (2014)

Carrying out molecular Dynamics simulations is a relevant way for understanding growth phenomena at the atomic scale. Initial conditions are defined for reproducing deposition conditions of plasma sputtering experiments. Two case studies are developed for highlighting the implementation of molecular dynamics simulations in the context of plasma sputtering deposition: ZrxCu1-x metallic glass and AlCoCrCuFeNi high entropy alloy thin films deposited onto silicon. Effects of depositing atom kinetic energies and atomic composition are studied in order to predict evolution of morphologies and atomic structure of MD grown thin films. Experimental and simulated X-ray diffraction patterns are compared.
Opposing effects of mitogenic and nonmitogenic lectins on lymphocyte activation. Evidence that wheat germ agglutinin produces a negative signal. (1976)

In an effort to clarify the mechanism by which certain plant lectins induce lymphocyte activation, we have studied amino acid (amino[14C]isobutyric acid) uptake in purified human lymphocytes exposed to mitogenic and nonmitogenic lectins. In confirmation of earlier work, mitogenic lectins (concanavalin A and two phytohemagglutinins) produced a dose-related, 2- to 10-fold increase in aminoisobutyric acid transport. Changes occurred as early as 2 hours and reached a maximum after 18 hours. The stimulation by concanavalin A was inhibited by alpha-methyl-D-mannoside but not by other selected monosaccharides, indicating that the effect is modulated through specific carbohydrate receptors. In contrast to the stimulation with concanavalin A and phytohemagglutinin, the nonmitogen wheat germ agglutinin inhibited aminoisobutyric acid transport, both in the presence and absence of the mitogenic lectins. The inhibition was seen over a broad wheat germ agglutinin dose range, was prevented by N-acetylglucosamine, a known inhibitor of wheat germ agglutinin binding, and did not appear to be associated with cytotoxicity. Comparative binding studies with radiolabeled concanavalin A and wheat germ agglutinin demonstrated that differences in transport occurred in cells containing comparable numbers of bound lectin molecules indicating that the failure of wheat germ agglutinin to stimulate a response was not a result of ineffective binding. The lack of stimulation by wheat germ agglutinin was not due to its inability to interact multivalently with membrane receptors since this lectin is divalent, produces capping and agglutination, and continues to inhibit aminoisobutyric acid transport even after the minimum valence was increased to 4 by cross-linking with glutaraldehyde. In contrast both divalent and tetravalent concanavalin A produced stimulation. Competitive binding studies with soluble wheat germ agglutinin or lectin attached to 300 A latex spheres revealed little or no competition for binding sites with radiolabeled concanavalin A, suggesting the two lectins are interacting with different receptors. This was further suggested by kinetic studies of aminoisobutyric acid transport which indicated that wheat germ agglutinin was probably affecting both the Vmax and Km of transport, whereas concanavalin A affected only the Vmax. While the mechanism by which concanavalin A and wheat germ agglutinin produce opposing effects on amino acid transport is not clear, since the two lectins appear to be interacting with different surface receptors we would suggest that they are perturbing microanatomically and functionally different domains on the lymphocyte plasma membrane.
ChemInform Abstract: A Facile, One‐Pot Procedure for the Preparation of 2‐Phenyl‐1,3‐propanediol Monocarbamate, a Metabolite of Felbamate. (2001)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Subframe Temporal Alignment of Non-Stationary Cameras (2008)

This paper studies the problem of estimating the sub-frame temporal offset between unsynchronised, non-stationary cameras. Based on motion trajectory correspondences, the estimation is done in two steps. First, we propose an algorithm to robustly estimate the frame accurate offset by analysing the trajectories and matching their characteristic time patterns. Using this result, we then show how the estimation of the fundamental matrix between two cameras can be reformulated to yield the sub-frame accurate offset from nine correspondences. We verify the robustness and performance of our approach on synthetic data as well as on real video sequences. In this work we present a method to find the subframe-accurate time offset between two or more recorded video sequences recorded by unsynchronised, non-stationary cameras. We address the problem of identifying the time relation between recorded sequences without the need to invade the scene to use special cameras. Main application of the method is multi-view video acquisition. Most multi-view processing algorithms rely on the assumption that the video sequences are temporally synchronised e. g. stereo vision, visual hull estimation and viewpoint interpolation algorithms. Synchronicity can be achieved by hardware synchronisation of the recording cameras. While this is feasible for laboratory or studio situations, it reduces the applicability of these methods in outdoor environments. Computing the subframe-accurate time offset between unsynchronised non-stationary cameras is necessary to apply multi-video algorithms to a wider range of scenes. Our method is based on tracking feature points and the resulting trajectories. It is divided into two steps. First, we find the time offset up to per-frame accuracy by extracting salient points of trajectories and matching their time patterns. This is possible already with only one single trajectory. Camera viewing angle differences of up to 90 degrees can be handled, as long as the tracked feature points are visible in both sequences. Using this coarse alignment, we can reformulate the estimation of the fundamental matrix to directly find the time offset of the non-stationary cameras to subframe accuracy. The remainder of the paper is organised as follows: The next section summarises previous work. Section 3 formalises the problem, in Section 4 our approach to compute the per-frame accurate time shift is presented. In Section 5 we describe how sub-frame accuracy is achieved. Experiments and results on synthetic data with ground truth and real world sequences are presented in Section 6.
Collagen catabolism through Coll2-1 and Coll2-1NO2 and myeloperoxidase activity in marathon runners (2013)

To determine the influence of marathon on the serum levels of two markers of cartilage degradation, Coll2-1 and its nitrated form, Coll2-1NO2, and of a marker of neutrophils activation, the myeloperoxidase (MPO). Coll2-1, Coll2-1NO2, total and active MPO were measured in 98 marathon runners without joint pain and with an average age of 47 years. Sera were taken at rest right before the departure and within 30 min after the marathon. The subjects were submitted to a questionnaire concerning their physical activity and their life style. The levels of Coll2-1, Coll2-1NO2 and active MPO were not affected by age, body mass index, sex or performance. The levels of total MPO were higher in female than in male (p < 0.05), but were not affected by the other parameters. After the marathon, Coll2-1 and Coll2-1NO2 concentrations were slightly but systematically decreased. The total and active MPO concentrations were increased by 2 to 3-fold in comparison to the pre-marathon values (p < 0.001 for total and active MPO). The active MPO/total MPO ratio was significantly enhanced after the marathon (p < 0.001). The variation of total MPO during the marathon was negatively correlated with the training time per week (r = -0.34; p = 0.009). The serum levels of Coll2-1 and Coll2-1NO2 were slightly decreased by marathon, indicating that intensive running could reduce cartilage catabolism. Furthermore, Coll2-1NO2 was not correlated with the total and active MPO indicating that Coll2-1 nitration did not result of a systemic oxidative phenomenon but reflects local changes.
Clinical Success of Antibody Therapeutics in Oncology (2007)

The antibodies approved for the treatment of diseases, including cancer, have been developed predominantly based on the understanding and identification of key targets involved in disease pathology. Thus, for oncology, marketed antibodies to epidermal growth-factor receptors/human epidermal growth-factor receptor and vascular endothelial growth factor treat cancer by blocking the function of these targets that are crucial for tumor progression. The success in designing and developing antibody-based cancer therapy depends largely on selecting suitable targets. Advancements toward earlier detection and improved outcomes with new targeted therapies promise to transform cancer into a chronic and manageable condition rather than a uniformly fatal disease. Advances in gene-expression analysis have enabled large-scale gene profiling to identify “tumor-specific” antigens. One of the more important activities of antibodies is to help trigger cellular immune responses against various targets, such as a pathogen, a pathogen-infected host cell, or a tumor cell.
Roles and Effects of TiN and Pt Electrodes in Resistive-Switching HfO2 Systems (2011)

We investigate the roles of TiN and Pt materials used as electrodes in resistive-switching HfO2 systems. Well-behaved reset operation is observed on condition Pt is used as anode, which together with the strong effect of thin insert layers (IL) indicates that the reset switching is favored at the HfO2\Pt interface. However, switching properties are hampered by yield and reliability issues associated to oxygen runaway at forming operation and caused by the Pt permeability to oxygen. TiN\HfO2\(IL)\Pt cells show better reliability due to improved oxygen buffering. The non-polar, unipolar and bipolar switching modes are discussed as originating from similar underlying physical mechanisms.
Characterization of the receptor for heat-stable enterotoxin from Escherichia coli in rat intestine. (1986)

The receptor for the heat-stable enterotoxin (ST) from Escherichia coli was solubilized with Lubrol-PX from rat intestinal brush-border membranes and characterized. The binding kinetics and analog specificity of the solubilized receptor were virtually identical to those obtained with the membrane-bound receptor. Furthermore, the regulation of the receptor's affinity by cations was also maintained after solubilization, indicating a conservation of the toxin-binding site after removal of the receptor from its membrane environment. Gel filtration and sucrose density gradient sedimentation studies gave a Stokes radius of 5.5 nm and a sedimentation coefficient of 7.0 S for the solubilized receptor. The isoelectric point of the receptor was determined as 5.5 using Sephadex isoelectric focusing electrophoresis. In all of these separation techniques, the ST receptor showed a single peak of activity that was clearly separated from that of guanylate cyclase. When 125I-ST was cross-linked to brush-border membranes with disuccinimidyl suberate, the affinity-labeled receptor solubilized with 0.1% Lubrol-PX eluted at a similar position as the native receptor on gel filtration chromatography. Analysis of the affinity-labeled receptor by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the presence of reducing agent and by autoradiography revealed the presence of three specifically labeled polypeptides with apparent molecular weights of 80,000, 68,000, and 60,000. These results suggest that the ST receptor is solubilized by Lubrol-PX in an active form with preservation of its regulation by cations. Also, the ST receptor is separable from particulate guanylate cyclase indicating that the receptor is coupled to the activation of guanylate cyclase by an as yet undefined mechanism. Three subunit peptides may constitute a binding region of the receptor.
Experimental Investigations of Acid Fracturing in Layered Carbonate Rocks Utilizing Chelating Agents (2023)

One of the methods to improve carbonate formation productivity is acid fracturing. The acid injection creates dissolution along the fracture, which improves fracture conductivity. This study investigated chelating agents such as glutamic diacetic acid and ethylene diamine triacetic acid on acid fracturing treatments to sustain the conductivity of layered minerals of carbonate formations. Chelating agents are less reactive than HCl and do not need large quantities of corrosion inhibitors, especially in high-temperature environments. Three cylindrical samples of 1.5 in. × 6 in. were cored from casted layered calcite and dolomite. The roughness and hardness of the fracture surface before and after the stimulation have been examined. The fracture conductivity was also evaluated before and after acid etching using a core flooding setup at different flow rates under four closure stress values. Inductively coupled plasma analysis has been carried out to estimate rock dissolution based on quantifying calcium and magnesium ions. Results showed that chelating agents have improved fracture conductivity and resulted in a sufficiently rougher fracture surface compared to HCl. The rock samples’ surface hardness has been reduced relatively post-treatment, with chelating agents being gentler on the rock. The novelty of this study is that for the first time, chelating agents have been tested as acid fracturing fluids on carbonate reservoirs for generating sustainable conductivity.
Dual-Polarization Bandwidth-Bridged Bandpass Sampling Fourier Transform Spectrometer from Visible to Near-Infrared on a Silicon Nitride Platform (2022)

On-chip broadband optical spectrometers that cover the entire tissue transparency window (λ = 650-1050 nm) with high resolution are highly demanded for miniaturized biosensing and bioimaging applications. The standard spatial heterodyne Fourier transform spectrometer (SHFTS) requires a large number of Mach-Zehnder interferometer (MZI) arrays to obtain a broad spectral bandwidth while maintaining high resolution. Here, we propose a novel type of SHFTS integrated with a subwavelength grating coupler (SWGC) for the dual-polarization bandpass sampling on the Si<sub>3</sub>N<sub>4</sub> platform to solve the intrinsic trade-off limitation between the bandwidth and resolution of the SHFTS without having an outrageous number of MZI arrays or adding additional active photonic components. By applying the bandpass sampling theorem, the continuous broadband input spectrum is divided into multiple narrow-band channels through tuning the phase-matching condition of the SWGC with different polarization and coupling angles. Thereby, it is able to reconstruct each band separately far beyond the Nyquist criterion without aliasing error or degrading the resolution. We experimentally demonstrated the broadband spectrum retrieval results with the overall bandwidth coverage of 400 nm, bridging the wavelengths from 650 to 1050 nm, with a resolution of 2-5 nm. The bandpass sampling SHFTS is designed to have 32 linearly unbalanced MZIs with the maximum optical path length difference of 93 μm within an overall footprint size of 4.7 mm × 0.65 mm, and the coupling angles of SWGC are varied from 0° to 32° to cover the entire tissue transparency window.
Large-Scale Cover Song Recognition Using the 2D Fourier Transform Magnitude (2012)

Large-scale cover song recognition involves calculating item-to-item similarities that can accommodate differences in timing and tempo, rendering simple Euclidean measures unsuitable. Expensive solutions such as dynamic time warping do not scale to million of instances, making them inappropriate for commercial-scale applications. In this work, we transform a beat-synchronous chroma matrix with a 2D Fourier transform and show that the resulting representation has properties that fit the cover song recognition task. We can also apply PCA to efficiently scale comparisons. We report the best results to date on the largest available dataset of around 18,000 cover songs amid one million tracks, giving a mean average precision of 3.0%.
Responsiveness of Endoscopic Indices of Disease Activity for Crohn’s Disease (2017)

Although both the SES-CD and CDEIS are valid measures of endoscopic disease activity that are moderately responsive to changes in endoscopic disease activity, the SES-CD displayed numerically greater responsiveness in this data set.
PIP4Ks Suppress Insulin Signaling through a Catalytic-Independent Mechanism (2019)

Insulin stimulates the conversion of phosphatidylinositol-4,5-bisphosphate (PI(4,5)P<sub>2</sub>) to phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P<sub>3</sub>), which mediates downstream cellular responses. PI(4,5)P<sub>2</sub> is produced by phosphatidylinositol-4-phosphate 5-kinases (PIP5Ks) and by phosphatidylinositol-5-phosphate 4-kinases (PIP4Ks). Here, we show that the loss of PIP4Ks (PIP4K2A, PIP4K2B, and PIP4K2C) in vitro results in a paradoxical increase in PI(4,5)P<sub>2</sub> and a concomitant increase in insulin-stimulated production of PI(3,4,5)P<sub>3</sub>. The reintroduction of either wild-type or kinase-dead mutants of the PIP4Ks restored cellular PI(4,5)P<sub>2</sub> levels and insulin stimulation of the PI3K pathway, suggesting a catalytic-independent role of PIP4Ks in regulating PI(4,5)P<sub>2</sub> levels. These effects are explained by an increase in PIP5K activity upon the deletion of PIP4Ks, which normally suppresses PIP5K activity through a direct binding interaction mediated by the N-terminal motif VMLΦPDD of PIP4K. Our work uncovers an allosteric function of PIP4Ks in suppressing PIP5K-mediated PI(4,5)P<sub>2</sub> synthesis and insulin-dependent conversion to PI(3,4,5)P<sub>3</sub> and suggests that the pharmacological depletion of PIP4K enzymes could represent a strategy for enhancing insulin signaling.
Modified lifetime prediction for multilayer ceramic capacitors based on space charge evolution (2018)

Accurate lifetime prediction for multilayer ceramic capacitors (MLCCs) is essential to ensure the reliability of electronic systems. A prediction formula based on a physical model has been recently proposed as an alternative to the widely used empirical formula. In this study, we used thermally stimulated depolarization current measurements to demonstrate that the physical model should be modified for low electric fields (<10 V/µm). We propose a new formula for the conditions as well as a modified model that involves an overpotential factor. The new formula suggests that if the applied dc field is less than the threshold value, the breakdown of MLCCs will not occur.