gebhart/patrepeval huggingface dataset:
Unusually strong emission from an exciplex formed between benzenoid solvents and dibenzoylmethanatoboron difluoride. Formation of a triplex (1995)

Benzene derivatives give, in cyclohexane solution, a strongly emitting (Φ f up to 0.8) excited complex with dibenzoylmethanatoboron difluoride (DBMBF 2 ). The rate constant k ex for the complex formation varies between 3.5 × 10 9 and 2.6 × 10 10 M −1 s −1 depending on the benzene derivative, and the complex emission can already be detected at very low concentrations of the aromatics. This behaviour is different from that found in acetonitrile where the DBMBF 2 emission disappeared completely before the new emission of the complex could be detected. The position of the complex emission and its lifetime depend upon the redox potential of the aromatics: the lower the latter, the longer the lifetime and the more the emission is red-shifted. The monotonous increase of the lifetime and of the fluorescence quantum yield of the emission with the concentration of the aromatics has been interpreted on the basis of an equilibrium between the exciplex and excited DBMBF 2 . The equilibrium constant varies with the electron-donating property of the aromatics, from 2.7 for benzene to 560 M −1 for isodurene. A decrease in the excited complex lifetime or in its fluorescence quantum yield is observed in some cases when the aromatics concentration is close to that of the pure solvent. Such behaviour is believed to arise from a new equilibrium resulting from the interaction of the exciplex with a second molecule of the aromatics to form triplex species. A detailed kinetic study has been undertaken in case of p-xylene, and the rate constants of all the processes involved in the double equilibrium have been determined. No basic difference is observed in the rate constant for exciplex formation when a single or double equilibrium is assumed; on the other hand, large discrepancies are found in the exciplex deactivation processes, specially for the back reaction from the exciplex to excited DBMBF 2 . The equilibrium constants between DBMBF 2 and the exciplex, on one hand, and between the latter and the triplex are 56.6 and 0.68 M −1 , respectively, when the concentration of p-xylene in cyclohexane is 3.3 M. Keywords: fluorescence, exciplex, triplex, dibenzoylmethanatoboron difluoride, kinetics.
The Medial Trivector Approach in Total Knee Arthroplasty (1998)

This study compares the clinical results of the medial trivector approach to the standard parapatellar approach in primary total knee arthroplasty. Ten patients undergoing simultaneous bilateral total knee arthroplasty were included in this study. Right and left knees were randomized for a standard medial parapatellar arthrotomy or a medial trivector approach. Patients were assessed by the number of days to achieve straight leg raising and range of motion at discharge. In addition, knee scores were obtained at 6 weeks and 6 months with careful assessment of any pain or tenderness around the quadriceps mechanism. At 6 months, patients were tested on a KINCOM machine assessing their concentric and eccentric quadriceps strength. While there was no difference in total range of motion at the time of discharge, patients undergoing a medial trivector approach achieved independent straight-leg raising 2 days sooner than patients undergoing a standard medial parapatellar arthrotomy. No significant differences existed in knee scores, pain scores, or range of motion at 6 weeks or 6 months. KINCOM testing at 6 months revealed the knees undergoing trivector approach to be 15% stronger in concentric contractions. No complications were encountered with the use of the medial trivector approach in these patients. Subjectively, patients reported less discomfort and more strength in the knees having undergone a medial trivector approach. The medial trivector approach may enhance postoperative recovery without adversely affecting the quadriceps function following total knee arthroplasty. The medial trivector approach to the knee does not weaken quadriceps muscle function or adversely affect clinical results of total knee arthroplasty.
A Comparison of Analytical and Experimental Local Heat Fluxes in Liquid-Propellant Rocket Thrust Chambers (1962)

Experimental data are presented showing heat-flux distributions measured calorimetrically with several liquid-propellant rocket thrust-chamber configurations. Thrust levels of the experimental chambers were from 300 to 5000 lb. Enzian-type and axial-stream showerhead propellant injectors were utilized with hydrazine (N2H4) and nitrogen tetroxide (N2O4) propellants. Nozzle-contraction-area ratios of 8 to 1, 4 to 1, and 1.64 to 1 were tested, each having a 5-in. inlet diameter. Characteristic chamber lengths ranged from 16.95 to 62.8 in. The comparison between the experimental heat flux and the analytical heat flux using the method of Bartz [1] was found to be closest in the nozzle-expansion region. The experimental heat-flux measurements ranged between 80 per cent above and 45 per cent below the analytical estimates at the nozzle throat, however. These differences were dependent upon thrust-chamber configuration, injector type, and chamber pressure, and apparently resulted from nonideal combustion and flow characteristics. It is concluded that a priori determination of heat-flux distribution along the thrust-chamber length was possible only to a first approximation for the conditions of these tests.
The effects of immunosuppression on the development of (experimental) cataract. (1988)

The immunogenical response to heteroimmunization and its effects on the lens were studied in 10 healthy young rabbits who received human lens antigen in Freund's adjuvant, according to a schedule. Half the immunized rabbits were treated with prednisolone (the equivalent of 10 mg/kg) daily. All five animals who did not receive prednisolone developed precipitating antibodies to human lens protein, whereas only one out of the five prednisolone-fed animals developed antibodies. Slitlamp examination of the lenses at 16 weeks and 32 weeks post-immunization revealed small cortical lens opacities in three of the animals who also showed lens antibodies in their sera. None of the antibody-negative animals showed any lens lesions (prednisolone treated).
[Resistance of medical equipment to exposure to molds]. (1978)

When operating biomedical equipment and instruments in areas with tropical climate there arises danger of their microbiological damage. All pieces of equipment and instruments that have to meet requirements as to their resistance to the action of moulds are subjected to testing for mould-resistance. The paper sets forth the results of such tests and their analysis. The resistance of the equipment and instruments depends on the physical and chemical properties and on the technology of manufacture of their materials. The results of the analysis of the results obtained served as a background for recommendations as to the use of resistant materials and effecting measures raising their quality. Such measures include the choice of resistent components, biocides, additives and admixtures to materials and coatings.
Dynamically reconfigurable embedded software-does it make sense? (2002)

A dynamically reconfigurable real-time software (DRRTS) paradigm can be used effectively in the design of embedded systems to provide many major advantages over conventional software development techniques. The benefits include rapid development which reduces development time and cost, ability to easily upgrade and maintain embedded software, and both analytic and practical tools for automated analysis and systematic fine tuning of the embedded system. Our current research is founded upon the Chimera Methodology, which demonstrated the feasibility of using dynamically reconfigurable software to control robots. However, there are still many design challenges in order to use it in an embedded system, which has less flexibility, severe limits on memory and CPU bandwidth, and more rigid timing constraints and reliability specifications. We have several ongoing projects which address some of the issues, in a strive towards the overall objective of creating a software infrastructure for developing dynamically reconfigurable embedded software.
An automatic contrast enhancement method based on stochastic resonance (2013)

Visual quality enhancement plays a vital role in low cost imaging systems, machine vision, industrial applications, remote sensing, face recognition systems and medical image interpretation etc. Growth of low cost image processing applications require image preprocessing which enhances details of an image. Most of the contrast enhancement papers apply desired contrast enhancement technique directly to enhance the given input image having poor contrast or contrast at any other undesired level. It is important to predict whether the contrast enhancement is needed for an image, to avoid the artifacts due to enhancement on the good image. In this paper, an algorithm to model images using its local contrast measure has been proposed, to classify and distinguish between the images having different contrast level. The input image is classified either as low contrast or high contrast image using the model. If the classified image is low contrast it will be enhanced using the Stochastic Resonance principle. The results show that the proposed automated procedure enhances the low contrast image better than the conventional enhancement methods.
Cellulose Acetate Membranes: Electron Microscopy of Structure (1964)

Electron photomicrographs of cellulose acetate membranes used in the reverse osmosis processof water desalination reveal a dense surface layer with a porous substructure. The high rate oftransmission for water can be correlated with the thickness of the dense layer on the air-driedsurface of the membrane.
Wellbore Trajectory Optimization Using Rate of Penetration and Wellbore Stability Analysis (2018)

Abstract Drilling deviated wells is a frequently used approach in the oil and gas industry to increase the productivity of wells in reservoirs with a small thickness. Drilling these wells has been a challenge due to the low rate of penetration (ROP) and severe wellbore instability issues. The objective of this research is to reach a better drilling performance by reducing drilling time and increasing wellbore stability. In this work, the first step was to develop a model that predicts the ROP for deviated wells by applying Artificial Neural Networks (ANNs). In the modeling, azimuth (AZI) and inclination (INC) of the wellbore trajectory, controllable drilling parameters, unconfined compressive strength (UCS), formation pore pressure, and in-situ stresses of the studied area were included as inputs. The second step was by optimizing the process using a genetic algorithm (GA), as a class of optimizing methods for complex functions, to obtain the maximum ROP along with the related wellbore trajectory (AZI and INC). Finally, the suggested azimuth (AZI) and inclination (INC) are premeditated by considering the results of wellbore stability analysis using wireline logging measurements, core and drilling data from the offset wells. The results showed that the optimized wellbore trajectory based on wellbore stability analysis was compatible with the results of the genetic algorithm (GA) that used to reach higher ROP. The recommended orientation that leads to maximum ROP and maintains the stability of drilling deviated wells (i.e., inclination ranged between 40°—50°) is parallel to (140°—150°) direction. The present study emphasizes that the proposed methodology can be applied as a cost-effective tool to optimize the wellbore trajectory and to calculate approximately the drilling time for future highly deviated wells.
Why Culture and Values Matter for Public Policy (2020)

Part One establishes the basic premise for the argument in the rest of the book. This is that culture and values have a significant role to play in determining how the policy process works and what its outcomes are. Each chapter in this Part sets out a different reason for adopting this premise.
Geometrically Exact Conservative Remapping (GECoRe): Regular Latitude–Longitude and Cubed-Sphere Grids (2008)

Abstract Land, ocean, and atmospheric models are often implemented on different spherical grids. As a conseqence coupling these model components requires state variables and fluxes to be regridded. For some variables, such as fluxes, it is paramount that the regridding algorithm is conservative (so that energy and water budget balances are maintained) and monotone (to prevent unphysical values). For global applications the cubed-sphere grids are gaining popularity in the atmospheric community whereas, for example, the land modeling groups are mostly using the regular latitude–longitude grid. Most existing regridding schemes fail to take advantage of geometrical symmetries between these grids and hence accuracy of the calculations can be lost. Hence, a new Geometrically Exact Conservative Remapping (GECoRe) scheme with a monotone option is proposed for remapping between regular latitude–longitude and gnomonic cubed-sphere grids. GECoRe is compared with existing remapping schemes published in the meteorological literature. It is concluded here that the geometrically exact scheme significantly improves the accuracy of the resulting remapping in idealized test cases.
Measurement of the hydrodynamic corrections to the Brownian motion of two colloidal spheres (1997)

The hydrodynamic coupling between two isolated 0.97 μm diameter polystyrene spheres is measured by reconstructing their Brownian motion using digital video microscopy. Blinking optical tweezers are used to facilitate data collection by positioning the spheres in the microscope’s focal plane and in close proximity to one another. The observed separation dependence of the spheres’ relative and center of mass diffusion coefficients agree with that predicted by low Reynolds number hydrodynamics and the Stokes-Einstein relation.
An Approach to Control Laws for Arm Motion (1984)

This paper is concerned with the investigation of arm motion between fixed boundary conditions within a two-dimensional space. An approach to the mathematical modeling and formulation ofthe control laws which govern arm reaching motion is presented.
Spatiotemporal Characteristics of Postischemic Hyperperfusion with Respect to Changes in T1, T2, Diffusion, Angiography, and Blood–Brain Barrier Permeability (2011)

The spatiotemporal dynamics of postischemic hyperperfusion (HP) remains incompletely understood. Diffusion, perfusion, T2, T1, angiographic, dynamic susceptibility-contrast magnetic resonance imaging (MRI) and magnetic resonance angiography were acquired longitudinally at multiple time points up to 7 days after stroke in rats subjected to 30-, 60-, and 90-minutes middle cerebral artery occlusion (MCAO). The spatiotemporal dynamics of postischemic HP was analyzed and compared with T1, T2 and blood-brain barrier (BBB) changes. No early HP within 3 hours after recanalization was observed. Late (12 hours) HP was present in all animals of the 30-minute MCAO group (N=20), half of the animals in the 60-minute MCAO group (N=8), and absent in the 90-minute MCAO group (N=9). Dynamic susceptibility-contrast MRI and magnetic resonance angiography corroborated HP. Hyperperfusion preceded T2 increase in some animals, but HP and T2 changes temporally coincided in others. T2 peaked first at 24 hours whereas HP peaked at 48 hours after occlusion, and HP resolved by day 7 in most animals at which point the arteries became tortuous. Pixel-by-pixel tracking analysis showed that tissue did not infarct (migrated from core or mismatch at 30 minutes to normal at 48 hours) showed normal cerebral blood flow (CBF), whereas infarct tissue (migrated from core or mismatch at 30 minutes to infarct at 48 hours) showed exaggerated CBF, indicating that HP was associated with poor outcome.
Standardization of Critical Temperature Measurement based on IEC International Standard (2003)

For disseminating a ney IEC international standard of critical trmperature of NbTi,NbSn and Bi-2223 Composite Suterconductors, we develpted a measuring system and studied standardization of test method. The measuring system consisted of cryogenic reservoir, base plate, thermometer, voltmeter and current source. Various specimens of the Nbti, NbSn and Bi-2223 composite superconductors were tested using this system for measuring their critical temperatures. After measuring the resistance-temperature relation, the data were compensated with thermoelectric voltages for NbTi NbSn specimens. NbTi specimens showed 9.2 K ~ 9.5 K of transition temperature and NbSn specimen showed about 18 K. Bi-2223 specimens showed 104 K ~ 107 K of transition temperature.
PML and PSTD algorithm for arbitrary lossy anisotropic media (1999)

A general perfectly matched layer (PML) formulation is presented for lossy anisotropic media with arbitrary permittivity, permeability, and conductivity tensors. This PML is then used in a pseudospectral time-domain (PSTD) algorithm for solutions of electromagnetic fields in lossy anisotropic media. Numerical results verify the efficiency of the PML absorbing boundary condition and the PSTD algorithm.
The Use of Doppler Ultrasound to Assist with Sciatic Nerve Blocks (1991)

Twenty consecutive patients requiring surgical procedures on a lower extremity received leg blocks using a modification of Labat's classic approach. A Doppler ultrasound pencil probe was used to identify the dominant arterial structure exiting the sciatic notch with the sciatic nerve. A block needle was inserted in the same orientation as the probe until paraesthesias were elicited; then 25 ml of local anesthetic was injected. Successful block was achieved in one or two attempts in 70% of the patients.
Ghrelin Suppresses Inflammation and Neuronal Nitric Oxide Synthase in Focal Cerebral Ischemia Via the Vagus Nerve (2010)

The pathogenesis of stroke involves inflammation, apoptosis, and excitotoxicity, which is mediated in part by neuronal NO synthase (nNOS) activation. Ghrelin, an endogenous 28-amino acid peptide, is shown to exert antiapoptotic and anti-inflammatory properties. However, the effect of ghrelin in permanent focal cerebral ischemia and the role of the vagus nerve in its action remain unknown. To study this, male adult Sprague-Dawley rats underwent right-sided permanent middle cerebral artery occlusion (MCAO) with or without prior bilateral truncal vagotomy. This was followed by infusion of 4 nmol human ghrelin as treatment or saline as vehicle. Neurological deficit was assessed at 24 h after MCAO. Rats were killed thereafter, and brains were rapidly removed and analyzed for infarct size, markers of inflammation, excitotoxicity, and apoptosis. Compared with vehicle treatment, human ghrelin treatment in vagus nerve-intact rats after MCAO showed marked reduction in neurological deficit by 57% and infarct size by 25%. Middle cerebral artery occlusion resulted in increases in cerebral TNF-α, IL-6, neutrophil trafficking, matrix metalloproteinase 9 and nNOS gene expression, nitrotyrosine, and apoptosis. Human ghrelin treatment in vagus nerve-intact rats significantly decreased the above measurements. Human ghrelin treatment also improved 7-day survival and significantly decreased neurological deficit over the entire 7 days after MCAO in vagus nerve-intact rats compared with vehicle. Prior vagotomy, however, blunted human ghrelin's neuroprotective effects on neurological deficit, infarct size, TNF-α, neutrophil trafficking, nitrotyrosine, and apoptosis. Human ghrelin is thus a neuroprotective agent that inhibits inflammation, nNOS activity, and apoptosis in focal cerebral ischemia through a vagal pathway.
Design and simulation of high sensitive capacitive pressure sensor with slotted diaphragm (2012)

This paper presents a high sensitive MEMS capacitive pressure sensor for biomedical applications. Two sensor designs incorporating clamped and slotted diaphragm are implemented and compared to realize the pressure-sensitive components. The pressure sensor has been designed to measure pressures in the range of 0 to 60 mmhg that is in the range of intraocular pressure sensors. Intraocular pressure sensors are important in detection and treatment of an incurable disease called glaucoma. The capacitive pressure sensor is formed using p++ silicon diaphragm as a biocompatible material. The novelty of this method relies on p++si diaphragm includes some slots to reduce the effect of residual stress and stiffness of diaphragm. The slotted diaphragm makes capacitive pressure sensor more sensitive. That is more suitable for measuring intraocular pressure sensor. The results yield a sensitivity of 1.811×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> 1/Pa for the clamped and 5.96×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> 1/Pa for the slotted pressure sensor with a 0.55 × 0.55 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> diaphragm. Furthermore, the pull-in voltage for the clamped pressure sensor is 51v, while the pull-in voltage of the slotted one is 38v.
Accurate Microseismic Event Location Inversion Using a Gradient-Based Method (2012)

Abstract From the microseismic data collected during multi-stage hydraulic fracturing, we may pick out the first arrival times for both P- and S-waves for each event and at each geophone. With triaxial geophones, the azimuths of the events may be derived from the hodograms. The P- and S-wave arrival times contain the distance information from the event location to the geophones as well as the event initiating time. The azimuth from hodograms gives the orientation information of the event locations. Inverting these interpreted microseismic data yields the event location parameters, which can be used to characterize the hydraulic fractures for reservoir modeling. This paper presents an efficient gradient-based microseismic event location inversion method. The forward model that is used to calculate the first arrival times is the finite-difference solution of the Eikonal equation. A novel method is devised to obtain the gradient of the first arrival times to the event location parameters in addition to the first arrival times in one forward model run. The method is applied to a realistic multilayer shale gas reservoir with a horizontal well and several stages of hydraulic fractures. The results show that the first arrival times obtained from the surface geophones yield better event location parameter estimation assuming we can pick up the events from the surface geophone signal. When the geophones are placed downhole in nearby wells, the inverted event locations are less accurate than the ones with surface geophones but can have a relative good characterization fo the fracture propagation.