gebhart/patrepeval huggingface dataset:
The NASA fuel cell upgrade program for the Space Shuttle orbiter (2002)

As part of NASA's overall efforts to improve the Space Shuttle operations, a program to upgrade the existing fuel cell powerplant has begun. The upgrade will involve replacing the alkaline fuel cell (AFC) system with a proton exchange membrane (PEM) fuel cell system, resulting in a much lower life cycle cost of the powerplant. The Shuttle Fuel Cell Upgrade plan of the JSC/LeRC/JPL team includes the following key elements: (1) systems analyses to assure compatibility/maximum utilization by shuttle of the best PEM fuel cell characteristics; (2) short stack testing of the leading PEM fuel cell contractors' hardware; (3) detailed task objective (DTO) flight experiment to verify PEM system water management and thermal management under zero-g operation; (4) A downselect to the best PEM system; and (5) development of the flight hardware powerplant system, including, of course, both the power and accessory subsystems. The planned success-oriented, four year effort is a coherent program to develop a 20 kW PEM fuel cell powerplant. The current major program tasks under way are short stack testing and systems analyses.
Zolpidem, triazolam, and diazepam decrease distress vocalizations in mouse pups: differential antagonism by flumazenil and beta-Carboline-3-carboxylate-t-butyl ester (beta-CCt). (2001)

In response to stressful events, neonatal mice emit ultrasonic vocalizations (USVs), which are suppressed by BZ agonists. The present study examined the role of the benzodiazepine/alpha1 (BZ/alpha1) receptor subtype in the suppression engendered by the BZ/alpha1-preferring agonist zolpidem and the nonselective BZ agonists triazolam and diazepam. The role of BZ receptor subtypes was explored further by conducting antagonism studies using the BZ/alpha1-preferring antagonist beta-carboline-3-carboxylate-t-butyl ester (beta-CCt), in comparison with the nonselective BZ antagonist flumazenil. Mouse pups (CFW strain) were separated from their dam and littermates at day 7, and placed for 4 min in a test chamber with reduced ambient temperature (19 +/- 1 degrees C) for recording USVs, motor incoordination (measured as a pup rolling on its back per grid cross), and body temperature. Zolpidem, triazolam, and diazepam suppressed USVs in a dose-dependent manner, concomitant with increases in incoordination and augmentation of hypothermia. These effects of the three BZ agonists were blocked by flumazenil in a manner consistent with surmountable antagonism. The ability of zolpidem, but not triazolam or diazepam, to suppress USVs and augment hypothermia was antagonized by beta-CCt, whereas the increase in motor incoordination engendered by zolpidem, triazolam, and diazepam was not sensitive to beta-CCt administration. Collectively, these results suggest that zolpidem suppresses distress USVs in mouse pups by a mechanism distinct from that of typical BZs. Furthermore, suppression of distress USVs by zolpidem may involve BZ/alpha1 receptors and a nonanxiolytic mechanism, such as hypothermia.
Long-term Degradation Mechanism In Small Molecule Based OLEDs (2000)

Intrinsic degradation, which leads to the long-term decrease in the electroluminescence (EL) efficiency of the devices, has been a major limitation facing the new technology of organic light emitting devices (OLED). Recently we investigated degradation in OLEDs based on tris(8-hydroxyquinoline) aluminum (AlQ3), a widely used electroluminescent small molecule. These studies showed that injection of holes in AlQ3 is the main factor responsible for device degradation. Devices in which predominantly holes were transported through a 5 nm thick AlQ3 layer showed a significant decrease in the photoluminescence (PL) efficiency upon prolonged current flow. In the present work we will also show that similar devices constructed in such a way to allow only electron flow through AlQ3 did not show any decrease in PL efficiency under similar current driving conditions. This demonstrates that AlQ3 cations are unstable and their degradation products lead to device degradation, while AlQ3 anions are stable. Further studies of time resolved fluorescence show that the AlQ3 degradation products are fluorescence quenchers, which cause decrease in device efficiency during prolonged operation. Comparison between fluorescence and electroluminescence decay of AlQ3 shows that PL decay is consistently smaller than EL decay indicating that decrease of PL efficiency is not the only mechanism leading to EL degradation of AlQ3.
Geodesical Codebook Design for Precoded MIMO Systems (2009)

We propose a numerical method for finding packings of multiple-input and multiple-output (MIMO) semi-unitary precoding matrices in Grassmannian manifolds with different metrics. The proposed expansion-compression algorithm ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ECA</i> ) is practical, simple and produces efficient packings without the need for a sophisticated initialization. With chordal distance metric, the algorithm tends to converge into a degenerated point constellation, where two points contain identical as well as orthogonal columns and distance between them cannot increase further along geodesic. Therefore, we alternate between <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max-min<i/> and <i>min-max</i> clustering parts of <i>ECA</i> algorithm, where the latter prevents degenerated constellations. With Fubini-Study distance metric, the algorithm converges to best known packings without extra <i>min-max</i> processing.</i>
CD28-B7 interactions are not required for intrathymic clonal deletion (1993)

Activation of antigen specific T cells requires more than stimulation through the TCR-CD3 complex. A second or costimulatory signal is also required, and this second signal can be delivered by interactions between CD28 and B7, ligands expressed on T cells and antigen presenting cells respectively. We have examined the role of the CD28-B7 interaction in superantigen mediated T cell activation and intrathymic negative selection by blocking B7 molecules with a high affinity soluble ligand, CTLA4lg. In vitro T cell activation mediated by both virally encoded endogenous and exogenous bacterial superantigens was significantly blocked by the addition of CTL4Alg to cultures. However, intrathymic clonal deletion in vivo and in fetal thymic organ cultures was not inhibited by blocking B7 molecules. Therefore, although the CD28-B7 costimulation pathway is necessary for T cell activation, it does not appear to play a role in intrathymic clonal deletion.
Employing the mutual phase coherence of the overtones in musical sounds for audio source separation and reconstruction (2007)

Source separation from a monaural mixture of musical sounds is challenging. When only a single mixture of multiple sources is available, the method of independent component analysis may not be straightforwardly applied, and proposed source separation methods have relied on previous knowledge of the independent sources. Our method employs mutual correlations of the overtone phases of musical sounds to ascribe spectral features to individual sources. The phase versus time is computed from the analytical signal representation of the output of a set of adaptive band-pass filters that perform initial spectral separation. A small number of cleanly separable partials, usually the fundamentals, are then employed as references to which the remaining filter-bank outputs are correlated. To separate overlapping spectral features and ascribe the proper amount of power to each source, the phase of the reference signal is scaled to the harmonic frequency, and the amplitude of each overtone is estimated by computing the cross-correlation of the phase trajectories. To group sonic events in time, we employ the history of the signal itself, thus eliminating the need for prior information. We discuss this separation method and the audio quality of the reconstructed source signals, with examples and a quantitative perceptual metric.
MSC-PoL: Hybrid GaN–Si Multistacked Switched-Capacitor 48-V PwrSiP VRM for Chiplets (2023)

This article presents a multistack switched-capacitor point-of-load (MSC-PoL) voltage regulation module (VRM) with coupled magnetics for ultrahigh-current chiplet systems. In the MSC-PoL architecture, the stacked switched-capacitor cells split the high input voltage into several intermediate voltage rails, which are loaded with the switched-inductor cells to achieve soft charging and voltage regulation. Automatic capacitor voltage balancing and inductor current sharing are realized during the soft charging process. Many inductors of the switched-inductor cells are coupled into one and operated in interleaving to reduce the inductor current ripple and boost the transient speed. A 48-to-1-V/450-A VRM containing two MSC-PoL modules is built and tested, leveraging high-voltage GaN devices for the front end and high-current silicon devices for the back end. Two ladder-structured coupled inductor designs are developed and compared, one of which installs a leakage magnetic plate to adjust the leakage inductance for lower current ripple. Featuring 3-D stacked packaging, the entire power stage, gate drivers, and bootstrap circuits of one MSC-PoL module are enclosed into a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\frac{1}{16}$</tex-math></inline-formula> -brick/0.31-in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{3}$</tex-math></inline-formula> /6-mm-thick package. The peak efficiency, the full-load efficiency, and the full-load power density (including both gate loss and size) of the MSC-PoL prototype with and without using the leakage plate are 91.7% and 89.5%, 85.8% and 85.6%, and 621 and 724 W/in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{3}$</tex-math></inline-formula> , respectively. The 6-mm-thick MSC-PoL converter can be embedded into the chiplet or CPU socket, enabling power supply in package for extreme efficiency, density, and control bandwidth.
Structure and Composition of Non-Infectious Phosphate Calculi Formed in Patients with Low and High Urinary Phosphate Concentrations (2013)

Objective: The aim of this paper was to assess the relationships among chemical, phase and structural composition and etiopathogenic factors of non-infectious phosphate calculi formed in patients with low and high urinary phosphate concentrations, and to characterize the mechanism of their formation related on biochemical results. Material and Methods: Twelve samples of phosphate renal calculi were obtained, 4 from patients with low phosphaturia and 6 from patients with high urinary phosphate concentrations. Their chemical composition was determined qualitatively by energy dispersive X-ray analysis and quantitatively by spectrophotometric and thermal analysis; and their phase composition was determined by Fourier transform infrared transmission spectroscopy and X-ray diffraction. The structure of the calculi was assessed by scanning electron microscopy. Results: Non-infectious phosphate renal calculi of patients with low phosphaturia consist of poorly crystalline carbonate hydroxyapatite, whereas those of patients with high urinary phosphate concentrations consist of poorly crystalline hydroxyapatite with some amount of calcium oxalate crystals. Calculi of patients with high urinary phosphate concentrations are formed at urinary supersaturation with respect to hydroxyapatite and calcium oxalate about 4 times higher than in patients with low phosphaturia. Conclusion: In patients with low phosphaturia, the non-infectious phosphate renal calculi are formed in urine near pH 7 and contain only poorly crystalline carbonate hydroxyapatite. In patients with high urinary phosphate concentrations and hypercalciuria, the calculi are formed in urine near pH 6 and consist of both poorly crystalline hydroxyapatite and some amount of calcium oxalate crystals.
Study of the DecayD0→K+π− (2001)

Using a large sample of photoproduced charm mesons from the FOCUS experiment at Fermilab (FNAL-E831), we observe the decay D0-->K+pi- with a signal yield of 149+/-31 events compared to a similarly cut sample consisting of 36 760+/-195 D0-->K-pi+ events. We use the observed ratio of D0-->K+pi- to D0-->K-pi+ (0.404+/-0.085+/-0.025)% to obtain a relationship between the D0 mixing and doubly Cabibbo suppressed decay parameters.
Multiuser Interference during Synchronization Phase in UWB Impulse Radio (2006)

This paper analyzes the receiver's ability to differentiate between multiple users in ultra-wideband (UWB) impulse radio (IR) during the initial synchronization phase after a cold start, i.e., when the receiver is not yet synchronized with the user of interest. Because of multiple access interference (MAI), the receiver may combine the pulses of other users in a partially coherent way. In this case, the receiver should be able to reject all the interfering users in order to synchronize with the user of interest. For pseudo-random time-hopping (TH) spreading codes, the expected performance of the receiver to differentiate between the user of interest and the interfering users is analyzed and some relations with the code properties are shown. Numerical results for a multipath propagation channel and MAI are provided.
A testbed for simultaneous measurement of fiber near and far-field for the evaluation of fiber scrambling properties (2012)

To improve our understanding of fiber scrambling properties a test bed where fiber near-field and far-field can be measured simultaneously is described. A variety of measurements has been conducted with a selection of fibers from different vendors, including state-of-the-art octagonal and hexagonal fibers. After characterization of the test bench with respect to stability and resolution, scrambling measurements have been conducted using LEDs with central wavelengths ranging between 465-635 nm. The dependence on wavelength regarding to photometrical scrambling has been initially demonstrated. Moreover, two mechanical combined fiber cables have been analyzed that were made from octagonal-circular and hexagonal-octagonal fiber sections. In this context an apparatus for focal ratio degradation (FRD) measurements was assembled to compare different shaped fibers and fiber combinations. Finally, all these preliminary investigations will help in choosing a fiber with good radial scrambling performance for the next generation fiber-link of the fiber optic coupled Cassegrain echelle spectrograph FOCES intended to be operated at the 2.0m Fraunhofer Telescope at the Wendelstein Observatory.
Tribological properties of thin films made by atomic layer deposition sliding against silicon (2017)

Interfacial phenomena, such as adhesion, friction, and wear, can dominate the performance and reliability of microelectromechanical (MEMS) devices. Here, thin films made by atomic layer deposition (ALD) were tested for their tribological properties. Tribological tests were carried out with silicon counterpart sliding against ALD thin films in order to simulate the contacts occurring in the MEMS devices. The counterpart was sliding in a linear reciprocating motion against the ALD films with the total sliding distances of 5 and 20 m. Al2O3 and TiO2 coatings with different deposition temperatures were investigated in addition to Al2O3-TiO2-nanolaminate, TiN, NbN, TiAlCN, a-C:H [diamondlike carbon (DLC)] coatings, and uncoated Si. The formation of the tribolayer in the contact area was the dominating phenomenon for friction and wear performance. Hardness, elastic modulus, and crystallinity of the materials were also investigated. The nitride coatings had the most favorable friction and wear performance of the ALD coatings, yet lower friction coefficient was measured with DLC a-C:H coating. These results help us to take steps toward improved coating solutions in, e.g., MEMS applications.
Cover Image, Volume 15, Issue 1 (2021)

The front cover image is courtesy of Oak Ridge National Laboratory, U.S. Dept. Of Energy, and is based on the Review Article Economic Impact of Yield and Composition Variation in Bioenergy Crops: Populus trichocarpa by Renee Happs et al., https://doi.org/10.1002/bbb.2148. Photographed by Genevieve Martin.
Cavitation in shock wave lithotripsy (2003)

A case is presented for the important role of cavitation in stone comminution and tissue injury in shock wave lithotripsy (SWL). Confocal hydrophones and a coincidence algorithm were used to detect cavitation in kidney parenchyma. Elevated hydrostatic pressure dissolved cavitation nuclei and suppressed cell injury and stone comminution in vitro. A low-insertion-loss, thin, mylar film nearly eliminated stone erosion and crack formation only when in direct contact with the stone. This result indicates not only that cavitation is important in both cracking and erosion but also that bubbles act at the surface. Time inversion of the shock wave by use of a pressure-release reflector reduced the calculated pressure at bubble collapse and the measured depth of bubble-induced pits in aluminum. Correspondingly tissue injury in vivo was nearly eliminated. Cavitation was localized and intensified by the use of synchronously triggered, facing lithotripters. This dual pulse lithotripter enhanced comminution at its focus and reduced lysis in surrounding blood samples. The enhancement of comminution was lost when stones were placed in glycerol, which retarded bubble implosion. Thus, cavitation is important in comminution and injury and can be controlled to optimize efficacy and safety. [Work supported by NIH DK43381, DK55674, and FIRCA.]
Performance of a Hardware Scheduler for Many-core Architecture (2012)

A hardware scheduler for many-core architectures enables fast scheduling and allocation of fine granularity tasks to all cores. We present performance evaluation of a hardware scheduler for HyperCore, a many-core architecture. The evaluation is based on an architectural simulator, using multiple benchmarks representing a wide variety of inherent parallelism. Several architectural improvements are proposed, and various configurations of the scheduler are simulated. The results are analyzed, and are used to highlight the potential and the possible pitfalls of the architecture. It is shown that a scheduler with a capacity to schedule and terminate 10 instances per cycle, along with a task queue of as little as two slots near each core, is sufficient to utilize 256 cores. Other scheduling configurations are also analyzed.
Correlation between Reverse Voltage Characteristics and Bypass Diode Operation with Different Shading Conditions for c-Si Photovoltaic Module Package (2015)

A photovoltaic (PV) system generates electricity by installing a solar energy array; therefore, the photovoltaic system can be easily exposed to external factors, which include environmental factors such as temperature, humidity, and radiation. These factors—as well as shading, in particular—lead to power degradation. When there is an output loss in the solar cell of a PV module package, the output loss is partly controlled by the bypass diode. As solar cells become highly efficient, the characteristics of series resistance and parallel resistance improve, and the characteristics of reverse voltage change. A bypass diode is connected in parallel to the string that is connected in series to the PV module. Ideally, the bypass diode operates when the voltage is -0.6[V] around. This study examines the bypass diode operating time for different types of crystalline solar cells. It compares the reverse voltage characteristics between the single solar cell and polycrystalline solar cell. Special modules were produced for the experiment. The shading rate of the solar cell in the specially made solar energy module was raised by 5% each time to confirm that the bypass diode was operating. The operation of the bypass diode is affected not only by the reverse voltage but also by the forward bias. This tendency was verified as the number of strings increased.
Comparison of retinal vascular geometry in obese and non-obese children (2018)

Obese children have abnormal retinal vascular geometry. These findings suggest that childhood obesity is characterized by early microvascular abnormalities that precede development of overt disease. Further research is warranted to determine if these parameters represent viable biomarkers for risk stratification in obesity.
Chemically amplified resists based on polymer side‐chain rearrangement or electrophilic crosslinking (1992)

Abstract A variety of resist systems have been studied that owe their sensitivity to the occurrence of catalyzed electrophilic rearrangements or substitution processes. In most designs, polyfunctional or polymer‐bound benzylic ethers, esters, or alcohols are used in the key step of the reaction, which is initiated by protonation of the latent electrophilic moiety, resulting in formation of a carbocationic center. Thermal activation of the electrophilic process leads to the formation of new C–C bonds with liberation of a proton; therefore the overall process is catalytic and amounts to chemical amplification. A variety of polymers and active small molecules that provide access to both negative and positive tone images have been tested, and sensitivities as high as 0.1 mJ/cm 2 have been measured. In addition, several image reversal schemes involving either selective silylation of non‐exposed areas or the in situ photogeneration of base have been tested and are presented.
Screening of antimicrobial agents for in vitro radiation protection and mitigation capacity, including those used in supportive care regimens for bone marrow transplant recipients. (2010)

Antibiotic and antifungal agents used in supportive care regimens for bone marrow transplantation recipients contribute to a significant dose-modifying effect of otherwise lethal total body irradiation. To determine whether drugs used in supportive care and other commonly used antibiotics such as tetracycline function as radiation protectors or damage mitigators in vitro, 13 drugs were tested for radiation protection and radiation damage mitigation of 32D cl 3 hematopoietic progenitor cells in clonagenic survival curves in vitro. Antibiotic/Antifungal agents including cilastatin, amikacin, ceftazidine, vancomycin, tetracycline, doxycycline, ciprofloxacin, metronidazole, methacycline, minocycline, meclocycline, oxytetracycline and rolitetracycline were added in 1, 10, or 100 micromolar concentrations to murine interleukin-3-dependent hematopoietic progenitor cell line 32D cl 3 cells either before or after irradiation of 0 to 8 Gy. Control irradiated 32D cl 3 cells showed radiosensitivity comparable to freshly explanted mouse marrow hematopoietic progenitor cells (D(0) 1.1+/-0.1 Gy, N 1.5+/-0.4). Positive control GS-nitroxide JP4-039 (known radiation mitigator) treated 32D cl 3 cells were radioresistant (D(0) 1.2+/-0.1, N 5.8+/-2.4 (p=0.009)). Of the 13 drugs tested, tetracycline was found to be a significant radiation mitigator (D(0) 0.9+/-0.1, N 13.9+/-0.4 (p=0.0027)). Thus, the radiation dose-modifying effect of some antibiotics, but not those currently used in the supportive care (antibiotic/antifungal regimens) for marrow transplant patients, may act as radiation damage mitigators for hematopoietic cells as well as decreasing the growth and inflammatory response to microbial pathogens.
Saturation characteristics of fast photodetectors (1998)

Summary form only given. Photodetector saturation can limit the performance of high-power, high-frequency analog systems. Photodetectors saturate primarily because of space charge, which redistributes the electric field within the intrinsic region, resulting in reduced output and a sharp increase in harmonic distortion. Here, we report measurements of photodetector saturation current in both the time and frequency domains.