gebhart/patrepeval huggingface dataset:
Multilateral well modeling from compartmentalized reservoirs (2018)

The existence of compartmentalization in oil and gas fields have been a major industry challenge for decades. This phenomenon introduces some complexity and uncertainty in the prediction of well productivities and the overall hydrocarbon recovery factor. In the past, multiple vertical wells were drilled to increase recovery. The recent advancement of the multilateral and completions technology made multilateral wells a viable alternative to produce multiple reservoir compartments, most especially offshore. Reservoir compartments may possess a set of unique characteristics, such as average pressures, thicknesses, permeabilities, and porosity distribution. This variation in properties introduced complex dynamics in forecasting the commingled production figures and overall recovery factor from complex reservoir structures using advanced well systems. Existing analytical and semi-analytical productivity models due to the simplifying assumptions in their development are only suitable for first approximations and early estimates in field applications. In this work, a comparison is made between the more widely known finite difference numerical method and the finite volume numerical discretization method in field productivity predictions. The Matlab Reservoir Simulation Toolbox (MRST) which is a collection of open source codes, based on the finite volume discretization methodology is used to develop the reservoir compartment and multilateral well model used in this study. We investigate the pressure drop behavior over time through the lateral for a conventional well completion and compare with the pressure drop behavior for a smart well completion with downhole flow control devices for flow control and optimization. Several cases of compartmentalized reservoirs with faults of varying orientation and sealing capacity is then investigated. The production profile results obtained from the base reservoir case from MRST is compared to those from the IMEX simulator tool in CMG (Computer Modeling Group), a commercial reservoir simulator, based on the finite difference numerical discretization method. The results we obtain show a more accurate production profile prediction based on the finite volume method over the finite difference method, as expected. The ability of the simulation toolbox as well as the importance of using an improved and more efficient numerical discretization scheme in solving an increasingly complex array of reservoir structures and advanced well geometries, with multiphase fluid flow is demonstrated. Finally, an adjoint gradient – based method of optimization implemented in the toolbox is used to investigate the optimization potential of using the smart well completions versus a conventional well completion with the net present value as the objective function. Results obtained show that an investment in smart completions for the multilateral well ultimately yields a higher net cash flow and net present value over a conventional well of equivalent length designed without smart completions.
Techniques for optical demultiplexing in high bit rate communication systems (1995)

Five standard configurations for optical demultiplexing of optical time domain multiplexed signals are compared. In terms of component usage and strobe signal requirements they are surprisingly equivalent. Both fiber loop and Mach-Zehnder configurations are studied. Fiber rings yield good stability, while configurations based on fiber Mach-Zehnder interferometers, in return, offer the possibility of add/drop demultiplexing. A new Mach-Zehnder configuration is proposed, which requires less optical components, only one strobe signal and has no optical losses (except from excess losses in couplers and splices). The sensitivity to power levels, fiber attenuation, signal and strobe wavelengths, etc., are analyzed and a preliminary design for a 100 to 5/spl times/20 Gb/s demultiplexer is suggested.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Accurate Imaging of Multicomponent GPR Data Based on Exact Radiation Patterns (2007)

Scalar migration algorithms developed for three-dimensional seismic data are commonly used for imaging ground-penetrating radar (GPR) data. Yet, radar is a vector phenomenon, such that the GPR amplitudes and phases depend on the antenna orientations and wave propagation paths. To address this issue, vector imaging algorithms that fully account for the vector characteristics of GPR data are required. All previously developed vector imaging algorithms are based on far-field approximations of radiation patterns. We demonstrate the limited applicability of these algorithms and introduce a computationally efficient practically exact-field method that accounts for the far-, intermediate-, and near-field contributions to the radiation patterns. To compute rapidly the required "exact" radiation patterns, inverse fast Fourier transforms are applied to their horizontal wavenumber-frequency domain formulations, balancing the tradeoff between accuracy and efficiency by an appropriate oversampling in the wavenumber-frequency domain, and taking advantage of vertical wavenumber phase shifting. We include the exact radiation patterns in a multicomponent vector imaging scheme that jointly images copolarized and cross-polarized data. This scheme is tested on synthetic and field data containing dipping planar and near-planar structures. For both suites of data, high-quality multicomponent images with reflection amplitudes that are nearly independent of the antenna and reflector orientations are obtained
Picosecond Pulse Radiolysis of Direct and Indirect Radiolytic Effects in Highly Concentrated Halide Aqueous Solutions (2011)

Recently we measured the amount of the single product, Br(3)(-), of steady-state radiolysis of highly concentrated Br(-) aqueous solutions, and we showed the effect of the direct ionization of Br(-) on the yield of Br(3)(-). Here, we report the first picosecond pulse-probe radiolysis measurements of ionization of highly concentrated Br(-) and Cl(-) aqueous solutions to describe the oxidation mechanism of the halide anions. The transient absorption spectra are reported from 350 to 750 nm on the picosecond range for halide solutions at different concentrations. In the highly concentrated halide solutions, we observed that, due to the presence of Na(+), the absorption band of the solvated electron is shifted to shorter wavelengths, but its decay, taking place during the spur reactions, is not affected within the first 4 ns. The kinetic measurements in the UV reveal the direct ionization of halide ions. The analysis of pulse-probe measurements show that after the electron pulse, the main reactions in solutions containing 1 M of Cl(-) and 2 M of Br(-) are the formation of ClOH(-•) and BrOH(-•), respectively. In contrast, in highly concentrated halide solutions, containing 5 M of Cl(-) and 6 M of Br(-), mainly Cl(2)(-•) and Br(2)(-•) are formed within the electron pulse without formation of ClOH(-•) and BrOH(-•). The results suggest that, not only Br(-) and Cl(-) are directly ionized into Br(•) and Cl(•) by the electron pulse, the halide atoms can also be rapidly generated through the reactions initiated by excitation and ionization of water, such as the prompt oxidation by the hole, H(2)O(+•), generated in the coordination sphere of the anion.
Synthesis of biodegradable and flexible, polylactic acid based, thermoplastic polyurethane with high gas barrier properties (2013)

Abstract Polylactic acid ( PLA ) has the beneficial properties of good mechanical strength, biodegradability and biocompatibility, and these properties make it suitable for use as an environmentally friendly packaging material. However, its use has been limited by its brittleness and poor stability. In this work, we successfully developed an efficient synthesis scheme to improve the mechanical properties, flexibility and gas barrier properties of PLA ‐based polymers. Four different PLA ‐based thermoplastic polyurethane ( PLAPU ) polymers were synthesized through the reaction of PLA diol with hexamethylene diisocyanate, followed by chain extension with polycaprolactone ( PCL ) diol. The relative compositions of the hard PLA and the soft PCL diols in the PLAPU polymers were controlled systematically to optimize the physical properties of the polymers. For example, increasing the content of PCL resulted in higher molecular weight PLAPU polymers that had increased tensile strengths and elongations at break, but their moduli were decreased. At the optimized PLA : PCL ratio of 1:3, the PLAPU polymer had an excellent elongation at break of 1053% with a relatively high Young's modulus of 51.8 MPa . In addition, the gas barrier properties of the PLAPUs were significantly enhanced depending on the molecular weight and PCL content of the polymers. To demonstrate the feasibility of using PLAPU polymers for biodegradable packaging materials, hydrolytic degradation tests were performed in phosphate buffer solution, and the PLAPU polymers were degraded gradually at rates that depended on the content of PCL in the polymers. This optimized PLAPU polymer exhibited excellent flexibility and gas barrier property, as well as high elongation, demonstrating its potential utility as packaging materials. © 2013 Society of Chemical Industry
Innovations in Technology for the Treatment of Diabetes: Clinical Development of the Artificial Pancreas (an Autonomous System) (2011)

The Food and Drug Administration in collaboration with the National Institutes of Health presented a public workshop to facilitate medical device innovation in the development of the artificial pancreas (or autonomous system) for the treatment of diabetes mellitus on November 10, 2010 in Gaithersburg, Maryland. The purpose of the workshop was to discuss four aspects of artificial pancreas research and development, including: (1) the current state of device systems for autonomous systems for the treatment of diabetes mellitus; (2) challenges in developing this expert device system using existing technology; (3) clinical expectations for these systems; and (4) development plans for the transition of this device system toward an outpatient setting. The patients discussed how clinical science, system components, and regulatory policies will all need to harmonize in order to achieve the goal of seeing an AP product brought forward to the marketplace for patients to use.
Slow fracture model based on strained silicate structures (1984)

Slow crack growth data, molecular-orbital calculations, and vibrational spectroscopy results are used to develop an atomistic model for environmentally controlled fracture of silica glass. The model is based on chemically active bond defects generated by the strain field of the crack tip. Molecular-orbital results suggest that bond angle deformations are most effective in increasing the chemical activity of the Si–O–Si bond. Vibrational spectra identify silica polymorphs containing highly strained bonding configurations. A comparison of strained bond reactivity with crack growth results shows that strained silica polymorphs can be used to model the crack tip chemical reactions controlling slow fracture. Based on model complexes, a two-dimensional fracture model involving kink site nucleation and motion is developed. The model shows that the stress intensity dependence of the crack growth rate is controlled by the energy required to form chemically active defects in the silica structure. The absolute rate of fracture depends on the combined rates of active bond formation and chemical attack at strain induced defects. Crack growth data suggest that for silica, strain activation occurs prior to the adsorption of environmental chemicals.
Chemical bath deposition of vertically aligned TiO2 nanoplatelet arrays for solar energy conversion applications (2013)

We report a facile, scalable, and low cost chemical bath deposition of vertically aligned TiO2 nanoplatelet arrays on various substrates including fluorine-doped tin oxide coated glass substrates and their applications for photoelectrochemical (PEC) water splitting and dye sensitized solar cells. The TiO2 arrays consisting of single crystal rutile nanoplatelets with heights (film thicknesses) of up to 1 μm, lengths of up to 130 nm, and widths of ∼5 nm were grown via controlling oxidation and hydrolysis of TiCl3 at low pH (0.71–0.85) and low TiCl3 concentration (8–40 mM). As a photoanode for water oxidation in a PEC water splitting cell, the TiO2 nanoplatelets show excellent charge separation characteristics with a saturated photocurrent in 1 M KOH electrolyte under AM 1.5 G illumination of ∼0.4 mA cm−2 reached at an exceptionally low bias of −0.6 V vs. Ag/AgCl (0.4 V vs. reversible hydrogen electrode). Dye sensitized solar cells assembled using N719 dye sensitized-TiO2 nanoplatelet arrays also show promising performance with photoconversion efficiencies of 1.28% for as-synthesized (no thermal post-treatment) and 3.7% for annealed TiO2 nanoplatelets.
A Review of GaAs MESFET Gate Electrode Fabrication Technologies (1986)

This review is designed to give an overview of the processes that have been used to define gate electrodes for MESFET's. This is an important topic, because the size and structure of the MESFET gate basically determines the performance of the transistor, which in turn determines the performance of circuits. Therefore, considerable effort has been expended in developing a wide variety of techniques. This review covers some of these techniques: lift‐off using a single layer of positive photoresist, lift‐off using multilayer photoresist structures, deep UV and E‐beam lithography, self‐aligned processes, and some nonconventional techniques.
Propofol effectively inhibits lithium-pilocarpine- induced status epilepticus in rats via downregulation of N-methyl-D-aspartate receptor 2B subunit expression. (2012)

Status epilepticus was induced via intraperitoneal injection of lithium-pilocarpine. The inhibitory effects of propofol on status epilepticus in rats were judged based on observation of behavior, electroencephalography and 24-hour survival rate. Propofol (12.5-100 mg/kg) improved status epilepticus in a dose-dependent manner, and significantly reduced the number of deaths within 24 hours of lithium-pilocarpine injection. Western blot results showed that, 24 hours after induction of status epilepticus, the levels of N-methyl-D-aspartate receptor 2A and 2B subunits were significantly increased in rat cerebral cortex and hippocampus. Propofol at 50 mg/kg significantly suppressed the increase in N-methyl-D-aspartate receptor 2B subunit levels, but not the increase in N-methyl-D-aspartate receptor 2A subunit levels. The results suggest that propofol can effectively inhibit status epilepticus induced by lithium-pilocarpine. This effect may be associated with downregulation of N-methyl-D-aspartate receptor 2B subunit expression after seizures.
Atomic structure of the diamond (100) surface studied using scanning tunneling microscopy (1996)

Atomic resolution ultrahigh-vacuum scanning tunneling microscopy studies of chemical-vapor-deposition-grown epitaxial diamond (100) films are reported. After growth, the surface of the epitaxial films is amorphous at the atomic scale. After 2 min of exposure to atomic hydrogen at 30 Torr, the surface is observed to consist of amorphous regions and (2×1) dimer reconstructed regions. After 5 min of exposure to atomic hydrogen, the surface is observed to consist mostly of (2×1) dimer reconstructed regions. These observations are compared with a recent model for chemical-vapor-deposition diamond growth. Tunneling current versus voltage spectroscopy of undoped and boron-doped epitaxial diamond (100) films is also reported.
The combined effect of breast cancer risk factors (1977)

An extension of the logistic model (Cox, 1970) is applied to the prospective study of breast cancer in Guernsey (Bulbrook and Hayward, 1967). Four important risk factors, age at menarche, family history, age at first birth and etiocholanolone excretion, are identified and shown to have additive effects on a logistic scale for the probability of developing breast cancer. The feasibility of screening a high risk group of women is considered and shown unlikely to be of practical value.
Network Polymers Based on Epoxy Oligomers and Dicyandiamide (1986)

Abstract The formation of network polymers by curing epoxy oligomers with dicyandiamide was investigated. The oligomers had the structure It was shown that the reaction between hydroxyl and epoxy groups is important in this process. The strength‐deformation properties of the network polymers obtained were studied. Calculations of elastic active network chains were carried out by the method of branching processes. Good agreement was obtained between calculated and experimental data.
Association of neurotrophin receptor expression and differentiation in human neuroblastoma. (1995)

Interactions of the trk family of tyrosine kinase receptors with neurotrophins result in growth and maturational changes in neuronal cells. The continued progression, maturation, or regression of neuroblastoma, an embryonal, sympathetic nervous system-derived tumor of infants and children, might be governed by neurotrophic influences. Immunocytochemistry was utilized to evaluate TrkA, TrkB, and TrkC protein expression at the cellular level in the developing human fetal sympathetic nervous system and in a selection of neuroblastoma tumor specimens. TrkA and TrkC expression was identified in sympathetic ganglia and within the adrenal medulla, with intense TrkB expression restricted to paraganglia, of the normal developing human sympathetic nervous system. In neuroblastoma, pp140trkA expression correlated positively with favorable tumor stage (P = 0.0027) and favorable outcome (P = 0.026). No statistically significant correlation of TrkC expression with outcome was evident; however, both TrkA and TrkC expression was most apparent in tumor cells of increased differentiation. TrkB expression was primarily localized to cells within the fibrovascular tumor stroma. A model of neurotrophin receptor expression and neurotrophin reactivity with differentiation is proposed. The existence and spatial distribution of neurotrophin receptors in neuroblastoma lend supportive evidence that neurotrophic influences may be involved in tumor persistence or regression.
Decentralized trust management and accountability in federated systems (2004)

In this paper, we describe three key problems for trust management in federated systems and present a layered architecture for addressing them. The three problems we address include how to express and verify trust in a flexible and scalable manner, how to monitor the use of trust relationships over time, and how to manage and reevaluate trust relationships based on historical traces of past behavior. While previous work provides the basis for expressing and verifying trust, it does not address the concurrent problems of how to continuously monitor and manage trust relationships over time. These problems close the loop on trust management and are especially relevant in the context of federated systems where remote resources can be acquired across multiple administrative domains and used in potentially undesirable ways (e.g., to launch denial-of-service attacks).
Overproduction of fatty acids in engineered <i>Saccharomyces cerevisiae</i> (2014)

The long hydrocarbon fatty acyl chain is energy rich, making it an ideal precursor for liquid transportation fuels and high-value oleo chemicals. As Saccharomyces cerevisiae has many advantages for industrial production compared to Escherichia coli. Here, we attempted to engineer Saccharomyces cerevisiae for overproduction of fatty acids. First, disruption of the beta-oxidation pathway, elimination of the acyl-CoA synthetases, overexpression of different thioesterases and acetyl-CoA carboxylase ACC1, and engineering the supply of precursor acetyl-CoA. The engineered strain XL122 produced more than 120 mg/L of fatty acids. In parallel, we inactivated ADH1, the dominant gene for ethanol production, to redirect the metabolic flux to fatty acids synthesis. The engineered strain DG005 produced about 140 mg/L fatty acids. Additionally, Acetyl-CoA carboxylase was identified as a critical bottleneck of fatty acids synthesis in S. cerevisiae with a cell-free system. However, overexpression of ACC1 has little effect on fatty acids biosynthesis. As it has been reported that phosphorylation of ACC1 may influent its activity, so phosphorylation sites of ACC1 were further identified. Although the regulatory mechanisms remain unclear, our results provide rationale for future studies to target this critical step. All these efforts, particularly the discovery of the limiting step are critical for developing a "cell factory" for the overproduction of fatty acids by using type I fatty acids synthase in yeast or other fungi.
Use of Expanding Cement Improves Bonding and Aids in Eliminating Annular Gas Migration in Hobbs Grayburg-San Andres Wells (1985)

ABSTRACT Annular gas migration and poor cement bonding throughout much of the wellbore have been continual problems in the primary cementing of Hobbs Grayburg-San Andres Wells. This paper discusses the formulation of an expanding cement system and the implementation of good primary cementing techniques to improve cement bonding and to eliminate annular gas flow after cementing. The work is based on a review of previously unsuccessful attempts to control annular gas flow by conventional gas control methods typically used by the industry. Case histories, cement bond logs, previous primary cement slurries, and procedures used in the field are presented with possible explanations of why they failed to control the problem. The formulation of the primary cement system is outlined in detail including refinements made to the system during the 1984-85 drilling program.
Interplay between S<sub>1</sub> and S<sub>4</sub> Subsites in Kex2 Protease:  Kex2 Exhibits Dual Specificity for the P<sub>4</sub> Side Chain (1998)

The yeast Kex2 protease is the prototype of a family of eukaryotic proprotein processing proteases that includes PC1, PC2, and furin. The catalytic domains of these enzymes are homologous to the degradative serine proteases of the subtilisin family. Kex2 exhibits optimal activity toward substrates with Lys or Arg at P2 and Arg at P1 (Lys-Arg or Arg-Arg cleavage sites). However, mammalian proprotein processing proteases such as furin exhibit more stringent requirements for basic residues at P4 than at P2. Here we demonstrate that Kex2 protease also recognizes P4, with dual specificity for aliphatic and basic residues. Recognition of P4 is even more readily apparent in substrates having a poor P1 residue (Lys). Kinetic analysis of a series of otherwise identical fluorogenic substrates with Lys at P1 and different residues at P4 indicates that large, aliphatic P4 residues increase kcat/KM by 100-fold. However, smaller residues or acidic residues at P4 do not. P4 Arg also confers efficient cleavage on such a substrate, but the uncharged isostere of Arg, citrulline, does not. Kex2 may thus possess distinct subsites that recognize aliphatic or basic P4 side chains. Although a favorable P4 residue can partially compensate for the defects in kcat and kcat/KM seen with Lys in place of Arg at P1, this substitution resulted in a change in rate-determining step for all substrates examined. As previously seen in the case of subtilisin, effects of substitutions at the P1 and P4 positions were not independent, suggesting that interplay between these two positions is a common feature of substrate specificity for both processing proteases and degradative enzymes of the subtilisin superfamily.
Fluorescein Angiography and Hemangiomas of the Choroid (1967)

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