gebhart/patrepeval huggingface dataset:
Are There Hydrogen Bonds in Supercritical Water? (1997)

The proton NMR chemical shift has been measured for water from 25 to 600 °C and from 1 to 400 bar, conditions extending well beyond the critical point. Dilute solutes were employed as chemical shift references to avoid the effect of the varying magnetic susceptibility. The large changes in chemical shift (4.1 ppm) are interpreted as changes in the hydrogen bond network, because all other intermolecular interactions are known to result in much smaller effects. Using a linear relation between chemical shift and the mean number of hydrogen bonds, the NMR results show there are still 29% as many hydrogen bonds at 400 °C and 400 bar (ρ = 0.52 g/cm3 ) as for room temperature water. The present results are compared to other measurements and calculations.
Synthesis and Reactions of N‐Heterocyclic Carbene Boranes (2011)

Boranes are widely used Lewis acids and N-heterocyclic carbenes (NHCs) are popular Lewis bases, so it is remarkable how little was known about their derived complexes until recently. NHC-boranes are typically readily accessible and many are so stable that they can be treated like organic compounds rather than complexes. They do not exhibit "borane chemistry", but instead are proving to have a rich chemistry of their own as reactants, as reagents, as initiators, and as catalysts. They have significant potential for use in organic synthesis and in polymer chemistry. They can be used to easily make unusual complexes with a broad spectrum of functional groups not usually seen in organoboron chemistry. Many of their reactions occur through new classes of reactive intermediates including borenium cations, boryl radicals, and even boryl anions. This Review provides comprehensive coverage of the synthesis, characterization, and reactions of NHC-boranes.
Fabrication of P-Channel MOSFETs on 4H-SiC C-Face (2011)

We investigated the 4H-SiC C-face MOS interface properties around valence-band, and fabricated 4H-SiC C-face p-channel MOSFETs for the first time. For C-face p-channel MOSFETs, relatively low-temperature wet-gate-oxidation was preferable. Post-deposition-annealing for contact metal was found to degrade the C-face MOS interface around valence-band. Low-temperature (800°C) PDA in hydrogen including ambient was effective to some extent in order to suppress the degradation owing annealing. We obtained C-face p-channel MOSFET with normal FET operation by utilizing 900°C wet-gate-oxidation and 800°C PDA in He-H2 forming gas ambient.
High Quality Aluminum Oxide Passivation Layer for Crystalline Silicon Solar Cells Deposited by Parallel-Plate Plasma-Enhanced Chemical Vapor Deposition (2009)

We investigated hydrogenated aluminum oxide (a-Al1-xOx:H) as a high quality rear surface passivation layer of crystalline silicon solar cells. The a-Al1-xOx:H films were deposited by plasma-enhanced chemical vapor deposition (PECVD) using a mixture of trimethylaluminum (TMA), carbon dioxide (CO2), and hydrogen (H2) at a low substrate temperature of about 200 °C. The ratio of CO2 to TMA during deposition and thermal annealing after the film deposition are the key factors in achieving high quality passivation. A 28-nm-thick a-Al1-xOx:H film deposited by PECVD showed a low surface recombination velocity of about 10 cm/s.
Methanol Synthesis from CO2 and H2 over CuO–ZnO Catalysts Combined with Metal Oxides under 13 atm Pressure (1991)

Abstract The synthesis of methanol from CO2 and H2 in a flow reactor was studied over CuO–ZnO catalysts combined with ZrO2, MgO, Al2O3, or Cr2O3 under a presssure of 13 atm. CuO–ZnO–Al2O3, CuO–ZnO–ZrO2, and CuO–ZnO–MgO showed higher activity and higher selectivity for methanol than did CuO–ZnO. The selectivity for methanol formation became higher as the reaction temperature was lower, or any of the H2/CO2 ratio, the pressure and the space velocity were higher. On the basis of analyses by XRD, XPS, and ultraviolet diffused reflectance spectroscopy, the active centers of CuO–ZnO–ZrO2 seem to be a Cu+–ZnO species stabilized by ZrO2.
Heart rate variability estimation in photoplethysmography signals using Bayesian learning approach (2016)

Heart rate variability (HRV) has become a marker for various health and disease conditions. Photoplethysmography (PPG) sensors integrated in wearable devices such as smart watches and phones are widely used to measure heart activities. HRV requires accurate estimation of time interval between consecutive peaks in the PPG signal. However, PPG signal is very sensitive to motion artefact which may lead to poor HRV estimation if false peaks are detected. In this Letter, the authors propose a probabilistic approach based on Bayesian learning to better estimate HRV from PPG signal recorded by wearable devices and enhance the performance of the automatic multi scale-based peak detection (AMPD) algorithm used for peak detection. The authors' experiments show that their approach enhances the performance of the AMPD algorithm in terms of number of HRV related metrics such as sensitivity, positive predictive value, and average temporal resolution.
Active inlet flow control technology demonstration (2000)

Abstract This paper presents results from a joint Lockheed Martin/NASA Glenn effort to design and verify an ultra-compact, highly-survivable engine inlet subsonic duct based on the emerging technology of active inlet flow control (AIFC). In the AIFC concept, micro-scale actuation (∼mm in size) is used in an approach denoted ‘secondary flow control’ to intelligently alter a serpentine duct's inherent secondary flow characteristics with the goal of simultaneously improving the critical system-level performance metrics of total pressure recovery, spatial distortion, and RMS turbulence. In this approach, separation control is a secondary benefit, not a design requirement. The baseline concept for this study was a 4:1 aspect ratio ultra-compact ( LID = 2·5) serpentine duct that fully obscured line-of-sight view of the engine face. At relevant flow conditions, this type of duct exhibits excessive pressure loss and distortion because of extreme wall curvature. Two sets of flow control effectors were designed with the intent of establishing high performance levels to the baseline duct. The first set used two arrays of 36 co-rotating microvane vortex generators (VGs); the second set used two arrays of 36 micro air-jet (microjet) VGs, which were designed to produce the same ‘vorticity signature’ as the microvanes. Optimisation of the microvane array was accomplished using a design of experiments (DOE) methodology to guide selection of parameters used in multiple Computational Fluid Dynamics (CFD) flow solutions. A verification test conducted in the NASA Glenn W1B test facility indicated low pressure recovery and high distortion for the baseline duct without flow control. With microvane flow control, at a throat Mach number of 0·60, pressure recovery was increased 5%, and both spatial distortion and turbulence were decreased approximately 50%. Microjet effectors also provided significantly improved performance over the baseline configuration.
Candidate Indistinguishability Obfuscation and Functional Encryption for all Circuits (2013)

In this work, we study indistinguishability obfuscation and functional encryption for general circuits: Indistinguishability obfuscation requires that given any two equivalent circuits C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> and C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> of similar size, the obfuscations of C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> and C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> should be computationally indistinguishable. In functional encryption, cipher texts encrypt inputs x and keys are issued for circuits C. Using the key SK <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">C</sub> to decrypt a cipher text CT <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> = Enc(x), yields the value C(x) but does not reveal anything else about x. Furthermore, no collusion of secret key holders should be able to learn anything more than the union of what they can each learn individually. We give constructions for indistinguishability obfuscation and functional encryption that supports all polynomial-size circuits. We accomplish this goal in three steps: - (1) We describe a candidate construction for indistinguishability obfuscation for NC <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> circuits. The security of this construction is based on a new algebraic hardness assumption. The candidate and assumption use a simplified variant of multilinear maps, which we call Multilinear Jigsaw Puzzles. (2) We show how to use indistinguishability obfuscation for NC <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> together with Fully Homomorphic Encryption (with decryption in NC <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> ) to achieve indistinguishability obfuscation for all circuits. (3) Finally, we show how to use indistinguishability obfuscation for circuits, public-key encryption, and non-interactive zero knowledge to achieve functional encryption for all circuits. The functional encryption scheme we construct also enjoys succinct cipher texts, which enables several other applications.
Preparation of Highly Dispersed Ultrafine Barium Titanate Powder by Using Microbial‐Derived Surfactant (2003)

To uniformly disperse ultrafine BaTiO 3 particles with a stoichiometric composition and several tens of nanometers in diameter to primary particles during the sol–gel synthesis process, a new aqueous surfactant with a high hydrophilic group density and special cis‐structure was prepared from a microbial product and added to solution before the sol–gel synthesis reaction. Because of the rapid formation of large and porous aggregates which were 30–50 μm in diameter in suspension without addition of this unique structural surfactant, the prepared ultrafine BaTiO 3 particles caused rapid sedimentation in suspension. The addition of the surfactant in the range of 7.1 wt% for the synthesized BaTiO 3 particles made it possible to decrease the size of the aggregates in suspension as well as the sedimentation velocity while maintaining the stoichiometric composition. The optimum additive content to obtain the minimum aggregate size of about 100–200 nm in diameter and the highest dispersion stability in suspension while maintaining the stoichiometric composition of prepared ultrafine BaTiO 3 particles without other phases was determined at about 7.1 wt%. Because the excess addition of this surfactant at more than 8.5 wt% inhibited the uniform synthesis of BaTiO 3 particles, an amorphous phase with a highly specific surface area and a BaCO 3 phase formed in the synthesized particles.
Structural and functional identification of vasculogenic mimicry in vitro (2017)

Vasculogenic mimicry (VM) describes a process by which cancer cells establish an alternative perfusion pathway in an endothelial cell-free manner. Despite its strong correlation with reduced patient survival, controversy still surrounds the existence of an in vitro model of VM. Furthermore, many studies that claim to demonstrate VM fail to provide solid evidence of true hollow channels, raising concerns as to whether actual VM is actually being examined. Herein, we provide a standardized in vitro assay that recreates the formation of functional hollow channels using ovarian cancer cell lines, cancer spheres and primary cultures derived from ovarian cancer ascites. X-ray microtomography 3D-reconstruction, fluorescence confocal microscopy and dye microinjection conclusively confirm the existence of functional glycoprotein-rich lined tubular structures in vitro and demonstrate that many of structures reported in the literature may not represent VM. This assay may be useful to design and test future VM-blocking anticancer therapies.
Image Formation by Self-Calibration in Radio Astronomy (1984)

This review describes these self-calibration methods and their application to both conventional and very long baseline arrays and includes examples of the high-quality images that they produce. After first defining closure phase and closure amplitude in Section 2, we review conventional aperture synthesis methods in Sections 3 and 4. The new iterative self-calibration algorithms are the subject of Section 5. In Section 6 we consider the capabilities and limitations of these algorithms. Finally, in Section 7 we mention some applications in optical and infrared astronomy and in new radio instruments presently planned or under construction.
Synthesis and Comparison of Hyperbranched Aromatic Polyimides Having the Same Repeating Unit by AB<sub>2</sub> Self-Polymerization and A<sub>2</sub> + B<sub>3</sub> Polymerization (2003)

A new AB2 monomer, designed from a template of the repeating unit of the hyperbranched polyimides by nonideal A2 + B3 polymerization, was successfully prepared via a multistep synthesis. Hyperbranched polyimides, having the same repeating unit as that by nonideal A2 + B3 polymerization, were prepared from this new AB2 monomer by direct self-polycondensation in the presence of diphenyl (2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate (DBOP). Hyperbranched polyimides, with a molecular weight of 1.11 × 104 to 1.73 × 105 and an inherent viscosity of 0.12−0.17 dL/g, were obtained. As-prepared hyperbranched polyimides were soluble in DMF, DMAc, DMSO and NMP. By 1H NMR analysis, the degree of branching (DB) of the prepared hyperbranched polyimides was estimated to be around 0.50. By thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurement, their 5% weight loss temperatures and glass transition temperatures were found to be in the ranges 445−460 and 155−161 °C, respectively. A comparison between the hyperbranched polyimides by AB2 self-polymerization and nonideal A2 + B3 polymerization reveals that their physical properties, such as viscosity, thermal stability, and glass transition temperature, etc., are different from each other. Especially, a comparison between the plots of intrinsic viscosity [η] vs molecular weight Mw elucidates that their molecular shapes are also different each other. The examination of the chain entanglement and intermolecular interaction by employing a freeze-extracting technique reveals that hyperbranched polyimides by nonideal A2 + B3 polymerization have a certain extent of chain entanglement and intermolecular interaction. A comprehensive analysis finally suggests that hyperbranched polyimides by AB2 self-polymerization have a compact highly branching structure, while that by nonideal A2 + B3 polymerization have a low branching density topology.
Identification of a phosphoenolpyruvate:fructose phosphotransferase system (fructose-1-phosphate forming) in Listeria monocytogenes (1993)

Listeria monocytogenes is a gram-positive bacterium whose carbohydrate metabolic pathways are poorly understood. We provide evidence for an inducible phosphoenolpyruvate (PEP):fructose phosphotransferase system (PTS) in this pathogen. The system consists of enzyme I, HPr, and a fructose-specific enzyme II complex which generates fructose-1-phosphate as the cytoplasmic product of the PTS-catalyzed vectorial phosphorylation reaction. Fructose-1-phosphate kinase then converts the product of the PTS reaction to fructose-1,6-bisphosphate. HPr was shown to be phosphorylated by [32P]PEP and enzyme I as well as by [32P]ATP and a fructose-1,6-bisphosphate-activated HPr kinase like those found in other gram-positive bacteria. Enzyme I, HPr, and the enzyme II complex of the Listeria PTS exhibit enzymatic cross-reactivity with PTS enzyme constituents from Bacillus subtilis and Staphylococcus aureus.
Structure of Copper Microclusters Isolated in Solid Argon (1986)

Extended x-ray-absorption fine structure has been used in conjunction with the aggregation technique to investigate the structure of copper microclusters (7 to 15 \AA{} mean diameter). The crystallographic structure of the microclusters is consistent with an fcc lattice. A small contraction of the nearest-neighbor distance was measured as a function of cluster size.
Polymers: Structure and Properties (1989)

Structure and Bonding Additives Physical Properties Tensile Properties Mechanical Properties Properties of Selected Polymers Glossary
Dynamic cerebral autoregulation during repeated squat-stand maneuvers (2008)

Transfer function analysis of spontaneous oscillations in blood pressure (BP) and cerebral blood flow (CBF) can quantify the dynamic relationship between BP and CBF. However, such oscillation amplitudes are often small and of questionable clinical significance, vary substantially, and cannot be controlled. At the very low frequencies (<0.07 Hz), coherence between BP and CBF often is low (<0.50) and their causal relationship is debated. Eight healthy subjects performed repeated squat-stand maneuvers to induce large oscillations in BP at frequencies of 0.025 and 0.05 Hz (very low frequency) and 0.1 Hz (low frequency), respectively. BP (Finapres), CBF velocity (CBFV; transcranial Doppler), and end-tidal CO(2) (capnography) were monitored. Spectral analysis was used to quantify oscillations in BP and CBFV and to estimate transfer function phase, gain, and coherence. Compared with spontaneous oscillations, induced oscillations had higher coherence [mean 0.8 (SD 0.11); >0.5 in all subjects at all frequencies] and lower variability in phase estimates. However, gain estimates remained unchanged. Under both conditions, the "high-pass filter" characteristics of dynamic autoregulation were observed. In conclusion, using repeated squat-stand maneuvers, we were able to study dynamic cerebral autoregulation in the low frequencies under conditions of hemodynamically strong and causally related oscillations in BP and CBFV. This not only enhances the confidence of transfer function analysis as indicated by high coherence and improved phase estimation but also strengthens the clinical relevance of this method as induced oscillations in BP and CBFV mimic those associated with postural changes in daily life.
Analysis of Tyramine in Cheese by High Performance Liquid Chromatography (1990)

A simple and rapid analytical method was developed for the determination of tyramine in cheese using high performance liquid chromatography (HPLC) with a fluorescence detector (FL). The chromatography was performed on a LiChrosorb RP-Select B column (7μm, 4×250mm) with a mobile phase consisting of a mixture of 0.01M phosphate buffer (pH 7.5) and acetonitrile (9:1, v/v), and pumped at a flow rate of 1.0ml/min. Fluorometric detection was achieved with an emission wavelength of 305nm and the excitation wavelength of 225nm. Tyramine was extracted with 5% perchloric acid from cheese, followed by clean-up on a C18 cartridge.Average recoveries of tyramine from cheeses spiked at 1.0 and 10.0μg/g were found to be 98.1% and 97.2%, respectively. The detection limit of tyramine in cheese with this system was found to be 0.25μg/g.Tyramine was contained in 88% of 336 imported cheeses, 48% of 127 domestic cheeses and 100% of 62 domestic processed cheeses.The average concentrations in imported, domestic and domestic processed cheeses were 195.6, 37.6 and 19.0μg/g, respectively.
The effect of vitamin A on epithelial integrity (1999)

Vitamin A is the generic term for a variety of fat-soluble substances including retinol, retinyl palmitate and the provitamin A carotenoids such as all-trans-beta-carotene. Vitamin A is commonly known as the anti-infective vitamin and has an essential role in vision and cellular differentiation, the latter providing a unique core mechanism helping to explain the influence of vitamin A on epithelial barriers. Alterations in the epithelial lining of vital organs occur early in deficiency, suggesting a potentially important role for the barrier function. Vitamin A deficiency (VAD) is most commonly recognized in the eye. The conjunctival-impression cytology test detects the presence of larger irregular keratinized cells and the absence of mucous-secreting goblet cells, indicative of VAD. The method is simple, quick and sensitive in populations where VAD is present. In the respiratory tract, observational studies all show an association with VAD, although vitamin A supplementation studies appear to have little effect on respiratory disease. Organ-specific targeting may improve success rates. The dual-sugar intestinal-permeability test allows the effect of vitamin A supplementation to be monitored on the gastrointestinal tract. Two vitamin A supplementation studies were carried out recently in Orissa State, India. Healthy infants of weaning age were administered orally eight weekly doses of 5.0 mg retinol equivalents and hospitalized infants received one large oral dose 60 mg retinol equivalents in the form of retinyl palmitate. Improvements in gut integrity and haematological status were observed in both studies. In summary, the response of the eye to vitamin A supplementation is well established; the present review highlights some of the more recent observations examining the effects of vitamin A.
Command shaping applied to a flexible robot with configuration-dependent resonance (2006)

Joint flexibility is an intrinsic property in most industrial robot manipulators. Because of the great complexity of its model, the resonant frequencies of the two-link flexible-joint robot manipulator vary with the configuration of the manipulator. Our objective is to move the manipulator from point to point with the least amount of residual vibration at the end point in the shortest time possible. Two shaped command profiles, based on ramped sinusoidal basis function and segmented versine basis function, are compared against one another as well as against the unshaped bang-bang command profile. The segmented versine basis function was proved to be the most effective
Chemical and Engineering Factors Affecting Solar Central Receiver Applications of Ternary Molten Salts (1988)

We have investigated the feasibility of using molten salt mixtures that melt at relatively low temperatures (120°C to 180°C), which consist of a sodium/potassium nitrate mixture with added lithium or calcium nitrate, as working fluids in solar thermal energy systems. The chemical stability of these ternary mixtures at high temperature, a key unknown property, was determined experimentally. Ternary salt mixtures are somewhat less stable than the binary mixture currently used, but appear to be usable at maximum temperatures of 460°C to 550°C, depending on composition. The implications of the properties of ternary salt mixtures in the engineering design of solar central receivers, especially concerning operating temperature range, efficiency, and subsystem component costs, were determined for selected compositions.