gebhart/patrepeval huggingface dataset:
Microsecond Catalytic Partial Oxidation of Alkanes (1996)

A single layer of woven platinum-10 percent rhodium gauze was used as a catalyst for the partial oxidation of ethane, propane, n -butane, and isobutane. This configuration produced oxygen conversions of equal to or greater than 90 percent and had high selectivity to olefins and oxygenated hydrocarbons at contact times as short as 10 microseconds at atmospheric pressure. This reactor operates by rapid chemical heating (∼5 microseconds) followed by rapid quenching to avoid homogeneous reactions, which decompose products. Mixing of the cold unreacted gas passing between the gauze wires with the hot product gas results in rapid quenching (∼200 microseconds) of the products from ∼800° to ∼400°C. The rapid quenching avoids successive homogeneous decomposition reactions of unstable products such as olefins and aldehydes but still allows homogeneous chain reactions that produce these species. The strong variations in products with the feed alkane showed that the reaction pathways operating at ∼10 −5 seconds are quite different than those operating at longer residence times. These results could have a significant effect on the direct conversion of alkanes to oxygenates such as formaldehyde.
Endocannabinoids and Liver Disease. I. Endocannabinoids and their receptors in the liver (2007)

Cannabinoid receptors (CB1 and CB2) and their endogenous ligands (endocannabinoids) have recently emerged as novel mediators of liver diseases. Endogenous activation of CB1 receptors promotes nonalcoholic fatty liver disease (NAFLD) and progression of liver fibrosis associated with chronic liver injury; in addition, CB1 receptors contribute to the pathogenesis of portal hypertension and cirrhotic cardiomyopathy. CB2 receptor-dependent effects are also increasingly characterized, including antifibrogenic effects and regulation of liver inflammation during ischemia-reperfusion and NAFLD. It is likely that the next few years will allow us to delineate whether molecules targeting CB1 and CB2 receptors are useful therapeutic agents for the treatment of chronic liver diseases.
Overview of optical rectennas for solar energy harvesting (2013)

Although the concept of using optical rectenna for harvesting solar energy was first introduced four decades ago, only recently has it invited a surge of interest, with dozens of laboratories around the world working on various aspects of the technology. An optical rectenna couples an ultra-high-speed diode to a submicron antenna so that the incoming radiation received by the antenna is rectified by the diode to produce a DC power output. The result is a technology that can be efficient and inexpensive, requiring only low-cost materials. Conventional classical rectification theory does not apply at optical frequencies, necessitating the application of quantum photon-assisted tunneling theory to describe the device operation. At first glance it would appear that the ultimate conversion efficiency is limited only by the Landsberg limit of 93%, but a more sober analysis that includes limitation due to the coherence of solar radiation leads to a result that coincides with the Trivich-Flinn limit of 44%. Innovative antenna designs are required to achieve high efficiency at frequencies where resistive losses in metal are substantial. The diode most often considered for rectennas make use of electron tunneling through ultra-thin insulators in metal-insulator-metal (MIM) diodes. The most severe constraint is that the impedances of the antenna and diodes must match for efficient power transfer. The consequence is an RC time constant that cannot be achieved with parallel-plate MIM diodes, leading to the need for real innovations in diode structures. Technologies under consideration include sharp-tip and traveling-wave MIM diodes, and graphene geometric diodes. We survey the technologies under consideration.
Indol-3-ylcycloalkyl Ketones: Effects of N1 Substituted Indole Side Chain Variations on CB<sub>2</sub> Cannabinoid Receptor Activity (2009)

Several 3-acylindoles with high affinity for the CB(2) cannabinoid receptor and selectivity over the CB(1) receptor have been prepared. A variety of 3-acyl substituents were investigated, and the tetramethylcyclopropyl group was found to lead to high affinity CB(2) agonists (5, 16). Substitution at the N1-indole position was then examined. A series of aminoalkylindoles was prepared and several substituted aminoethyl derivatives were active (23-27, 5) at the CB(2) receptor. A study of N1 nonaromatic side chain variants provided potent agonists at the CB(2) receptor (16, 35-41, 44-47, 49-54, and 57-58). Several polar side chains (alcohols, oxazolidinone) were well-tolerated for CB(2) receptor activity (41, 50), while others (amide, acid) led to weaker or inactive compounds (55 and 56). N1 aromatic side chains also afforded several high affinity CB(2) receptor agonists (61, 63, 65, and 69) but were generally less potent in an in vitro CB(2) functional assay than were nonaromatic side chain analogues.
A speaker‐independent word recognition based on HMM using orthogonalized phonetic segment codebook (1994)

Abstract Matrix quantization (MQ) is a method which directly quantizes the spectrum‐time pattern. However, it has a problem in that the quantization error is relatively large compared to the vector quantization (VQ), since the dimension is large and the pattern variation is less. From such a viewpoint, this paper introduces the acoustic/phonetic structure called phonetic segment as the unit of MQ. The statistical matrix quantization (SMQ) is applied to the calculation of the error measure, where the subspace method, i.e., a statistical pattern recognition technique, is employed. The purpose of SMQ is to consider effectively the pattern variation by constructing the Orthogonalized phonetic segment codebook based on the eigenvector set representing the pattern variation for each phonetic segment. The training of HMM using the phonetic segment code sequence also is considered. The K‐best learning is proposed, where from the first to the K ‐th phonetic segment sequences are equally handled. Even though the K‐best learning is much simpler than VQ, it has equal or better output probability smoothing power, and can suppress the effect of the error in the conversion of the speech to the phonetic segment code sequence. Using the (SMQ/HMM + K‐best learning) method, a high speaker‐independent word recognition performance of 96.0 percent is obtained for the 100 word data set containing similar word pairs uttered by 10 unknown speakers.
Simulating respiratory loads and tuning of closed-circuit underwater breathing apparatus. (1997)

An experimental apparatus for simulating respiratory loads in closed-circuit underwater breathing systems comprises a partly submerged vertical tube having a dual path exit on the submerged end of the tube. One path is controlled by a valve that alters the inertance of the system, changes the natural frequency, and provides the tuning. The vertical tube provides elastic loading to simulate a counterlung or breathing bag in an underwater breathing apparatus (UBA). The experimental apparatus was connected to a breathing machine controlled by a signal generator to simulate a diver's breathing. The benefits of reactance tuning of this apparatus are demonstrated. A mathematical model describes both the simulator and UBA. The simulator can be used with human subjects to study respiratory response to changes in impedance.
Calebin‐A inhibits adipogenesis and hepatic steatosis in high‐fat diet‐induced obesity via activation of AMPK signaling (2015)

Taken together, these results demonstrated for the first time that Calebin-A suppressed adipocyte differentiation, prevented HFD-induced obesity, and improved hepatic steatosis, suggesting a novel application for the prevention and treatment of obesity and associated nonalcoholic fatty liver disease.
Ordered organic-organic multilayer growth (2011)

Crystalline order and orientation influence both the electronic and optical properties of thin organic crystalline films. Here, we demonstrate the quasiepitaxially ordered growth via organic vapor phase deposition of two organic materials, 1,4,5,8-naphthalene-tetracarboxylic-dianhydride and dibenzotetrathiafulvalene-tetracyanoquinodimethane on single-crystal substrates. To understand the quasiepitaxial orientations between the organic-inorganic and organic-organic lattices we compare geometrical lattice registry to full-structure van der Waals potential calculations, and find that only the complete description of the atomistic potential correctly matches experimentally observed orientations. We also demonstrate single-crystalline film growth of alternating multiple quasiepitaxial layers of these two organic semiconductors, and discuss this phenomenon in the context of incommensurate quasiepitaxy and surface energy matching, which is distinct from the lattice-matching criterion for inorganic heteroepitaxy.
Organosilane Polymers. IV. Polycarbosilane Precursors for Silicon Carbide. (1981)

The current objectives of this project are: (1) optimized preparations of tractable polycarbosilane precursors for silicon carbide; (2) conversion of such polycarbosilanes to silicon carbide including shaped articles thereof, such as fibers; and (3) development of fundamental understanding of the preparative and pyrolytic chemistry. One-step preparations of tractable polycarbosilanes are achieved through silicon-carbon bond-forming reactions of vinylic or chloromethyl (ClCH2-) silanes. These polymers are directly convertible to silicon carbide compositions by atmospheric pressure pyrolysis. Backbone branching is recognized as essential for practical conversion of such polycarbosilanes to silicon carbide.
In-Home Fall Risk Assessment and Detection Sensor System (2013)

Falls are a major problem in older adults. A continuous, unobtrusive, environmentally mounted (i.e., embedded into the environment and not worn by the individual), in-home monitoring system that automatically detects when falls have occurred or when the risk of falling is increasing could alert health care providers and family members to intervene to improve physical function or manage illnesses that may precipitate falls. Researchers at the University of Missouri Center for Eldercare and Rehabilitation Technology are testing such sensor systems for fall risk assessment (FRA) and detection in older adults' apartments in a senior living community. Initial results comparing ground truth (validated measures) of FRA data and GAITRite System parameters with data captured from Microsoft(®) Kinect and pulse-Doppler radar are reported.
Compact THz imaging detector (2013)

We describe preliminary design, modeling and test results for the development of a monolithic, high pixel density, THz band focal plane array (FPA) fabricated in a commercial CMOS process. Each pixel unit cell contains multiple individual THz band antennae that are coupled to independent amplifiers. The amplified signals are summed either coherently or incoherently to improve detection (SNR). The sensor is designed to operate at room temperature using passive or active illumination. In addition to the THz detector, a secondary array of Visible or SWIR context imaging pixels are interposed in the same area matrix. Multiple VIS/SWIR context pixels can be fabricated within the THz pixel unit cell. This provides simultaneous, registered context imagery and "Pan sharpening" MTF enhancement for the THz image. The compact THz imaging system maximizes the utility of a ~ 300 μm x 300 μm pixel area associated with the optical resolution spot size for a THz imaging system operating at a nominal ~ 1.0 THz spectral frequency. RF modeling is used to parameterize the antenna array design for optimal response at the THz frequencies of interest. The quarter-wave strip balanced bow-tie antennae are optimized based on the semiconductor fabrication technology thin-film characteristics and the CMOS detector input impedance. RF SPICE models enhanced for THz frequencies are used to evaluate the predicted CMOS detector performance and optimal unit cell design architecture. The models are validated through testing of existing CMOS ROICs with calibrated THz sources.
Implementation of time-of-flight on CPS HiRez PET scanner (2005)

Time-of-flight (TOF) positron emission tomography (PET) was studied and preliminarily developed in the 80s, but the lack of a scintillator able to deliver at the same time proper time resolution and stopping power has prevented this technique from becoming widespread and commercially available. The introduction of LSO in PET has made TOF-PET a feasible option: TOF reconstruction is being implemented in CPS HiRez PET scanner, both in Filtered-Back-Projection and OSEM3D. The measured time resolution of 1.2 ns (FWHM) allows for a signal-to-noise ratio increase of about 50% in patients of about 40 cm transaxial size. TOF reconstruction has shown the expected improvement in SNR, both in simulation and experimental data. In iterative reconstruction we observed that TOF-PET has a much faster convergence compared to conventional reconstruction and better consistency improves the SNR ratio
Learn to overfit better: finding the important parameters for learned image compression (2021)

For most machine learning systems, overfitting is an undesired behavior. However, overfitting a model to a test image or a video at inference time is a favorable and effective technique to improve the coding efficiency of learning-based image and video codecs. At the encoding stage, one or more neural networks that are part of the codec are finetuned using the input image or video to achieve a better coding performance. The encoder en-codes the input content into a content bitstream. If the finetuned neural network is part (also) of the decoder, the encoder signals the weight update of the finetuned model to the decoder along with the content bitstream. At the decoding stage, the decoder first updates its neural network model according to the received weight update, and then proceeds with decoding the content bitstream. Since a neural network contains a large number of parameters, compressing the weight update is critical to reducing bitrate overhead. In this paper, we propose learning-based methods to find the important parameters to be overfitted, in terms of rate-distortion performance. Based on simple distribution models for variables in the weight update, we derive two objective functions. By optimizing the proposed objective functions, the importance scores of the parameters can be calculated and the important parameters can be determined. Our experiments on lossless image compression codec show that the proposed method significantly outperforms a prior-art method where overfitted parameters were selected based on heuristics. Furthermore, our technique improved the compression performance of the state-of-the-art lossless image compression codec by 0.1 bit per pixel.
Active-Pixel Sensors With "Winner-Take-All" Mode (1998)

Circuits to generate the intensity\nreading and the coordinates of the\nbrightest pixel in each image would be\nadded to imaging photodetector arrays\nof the active-pixel-sensor (APS) type,\naccording to a proposal. For a given\nAPS, the additional circuitry for locating\nthe brightest pixel would be installed\nat the periphery of the basic\nAPS circuit. The additional circuitry\nwould thus not degrade the original\noptical properties or interfere with the\noriginal electronic functions of the\nAPS. The APS could be operated in its\nnormal image-readout mode or, optionally,\nit could be operated with the\nadditional circuitry in the brightest-pixel\nmode. Potential applications\ncould include star tracking or fast\ntracking of a moving laser-beam spot in\nlaser communication system.
Dynamics of Schmallenberg virus infection within a cattle herd in Germany, 2011 (2013)

In late 2011, the insect-transmitted Schmallenberg virus (SBV) emerged in Europe. In this study, a cattle farm located in the core region of the epidemic was closely monitored between May 2011 and January 2012. Up to the end of September every tested serum sample was negative by an SBV-specific antibody ELISA, suggesting the absence of an infection before autumn 2011. Around the end of September/beginning of October SBV genome was detected in blood samples of some animals, and a few cows exhibited fever during that period. Starting at the end of September the first cows seroconverted; the within-herd prevalence reached 100% within barely 1 month. Consequently, SBV spread rapidly in the tested herd during the vector season of 2011.
Fluxons in Josephson transmission lines: new developments (1995)

We review several of the most recently developed topics in the field of fluxon dynamics in Josephson junctions.The main emphasis is placed on new systems and experimental methods which are currently under investigation.The selected topics are (i) fluxons in stacked long Josephson junctions, (ii) dynamics of one-dimensional underdamped Josephson junction arrays and (iii) spatially resolved investigations of fluxon dynamics.Future prospects are also discussed.
A General Description of Linear Time-Frequency Transforms and Formulation of a Fast, Invertible Transform That Samples the Continuous S-Transform Spectrum Nonredundantly (2009)

Examining the frequency content of signals is critical in many applications, from neuroscience to astronomy. Many techniques have been proposed to accomplish this. One of these, the S-transform, provides simultaneous time and frequency information similar to the wavelet transform, but uses sinusoidal basis functions to produce frequency and globally referenced phase measurements. It has shown promise in many medical imaging applications but has high computational requirements. This paper presents a general transform that describes Fourier-family transforms, including the Fourier, short-time Fourier, and S- transforms. A discrete, nonredundant formulation of this transform, as well as algorithms for calculating the forward and inverse transforms are also developed. These utilize efficient sampling of the time-frequency plane and have the same computational complexity as the fast Fourier transform. When configured appropriately, this new algorithm samples the continuous S-transform spectrum efficiently and nonredundantly, allowing signals to be transformed in milliseconds rather than days, as compared to the original S-transform algorithm. The new and efficient algorithms make practical many existing signal and image processing techniques, both in biomedical and other applications.
Favorable noise uniformity properties of Fourier-based approaches to interpolation in helical CT with implications for 3D visualization (2002)

This paper describes and evaluates two new approaches to longitudinal interpolation in single-slice helical CT that represent a step toward the goal of achieving essentially isotropic resolution and noise properties in reconstructed helical CT volumes. Both approaches exploit the fast Fourier transform and the Fourier shift theorem to generate from the helical projection data a set of fan-beam sinograms corresponding to equispaced transverse slices. Slice-by-slice reconstruction is then performed by use of two-dimensional fan-beam algorithms. The first approach, called 360FT, makes use only of the directly measured projection data, but the second approach, called 180FT, exploits the redundancy of fan-beam data acquired over 360/spl deg/ to generate a second set of longitudinal samples at each projection angle and bin. These approaches, and particularly the 180FT approach, have been shown under certain conditions to produce reconstructed volumes with more isotropic resolution and aliasing properties than do existing approaches based on the use of linear interpolation. We present evidence that the approaches also have favorable noise uniformity properties relative to currently used approaches.
Lamb wave devices using capacitive micromachined ultrasonic transducers (2001)

Lamb wave devices based on capacitive micromachined ultrasonic transducers (CMUTs) have been built on 500-μm-thick silicon wafers for frequencies in the vicinity of 1 MHz. CMUTs have been used to both excite and detect Lamb waves in the substrate. This configuration eliminates the need for piezoelectric materials, which are not compatible with the existing integrated circuit (IC) fabrication techniques, and allows easy integration of Lamb wave devices and electronics on the same wafer. Finite element analysis of the devices shows that the lowest order antisymmetric Lamb wave (A0) is the dominant mode in the substrate in this frequency range. This result is also confirmed by demonstration experiments.
Temporal and Resolution Layering in Advanced Television (1996)

Current proposals for Advanced Television for the United States are based upon the premise that temporal and resolution layering are inefficient. These proposals therefore only provide a menu of individual formats from which to select, but each format only encodes and decodes a single resolution and frame rate. In addition, it is being suggested by some people that interlace is required, due to their claimed need to have one thousand lines at high frame rates, but based upon the notion that such images cannot be compressed within the available 18mbits/second. — This paper discusses an approach to image compression which demonstrably achieves thousand line image compression at high frame rates with high quality. It also achieves both temporal and spatial scalability at this resolution at high frame rates within the available 18mbits/second. This technique efficiently encodes 2 MegaPixel images at 72 frames per second, achieving over twice the compression ratio being proposed by ACATS for advanced television. Further, this proposed technique is more robust than the current unlayered ACATS format proposal for advanced television, since all of the bits may be allocated to the lower resolution base layer when stressful image material is encountered. — Thus, a number of key technical attributes are provided by this proposal, allowing substantial improvement over the ACATS proposal. These improvements include: the replacement of numerous resolutions and frame rates with a single layered resolution and frame rate; no need for interlace in order to achieve a thousand lines of two million pixels at high frame rates: and compatibility with computer displays through the use of 72 frames per second.
Design challenges and guidelines for free-space optical communication links using orbital-angular-momentum multiplexing of multiple beams (2016)

In this paper, recent studies on the potential challenges for an orbital angular momentum (OAM) multiplexing system were reviewed. The design guideline for a practical OAM multiplexing system were investigated in term of (i) the power loss due to the beam divergence and limited-size receiver, and (ii) the channel crosstalk due to the misalignment between the transmitter and receiver.