gebhart/patrepeval huggingface dataset:
Coal gasification catalysis mechanisms. Final report, September 29, 1980 to November 29, 1982. [5 coal chars; 23 catalyst compounds, 5 binary and 2 ternary eutectics] (1982)

A two-year effort to explore the fundamental aspects of catalytic coal char gasification is summarized. Twenty-three different pure catalysts, five binary and two ternary eutectics were used in concentrations ranging from two to fifty percent. Cation effects were monitored at constant anion; anion effects were monitored at constant cation. Mineral effects, both added and indigenous, were studied. Thirteen different gaseous atmospheres were utilized. Kinetic parameters were determined for several hundred gasification trials via thermogravimetry. These data were compared to those obtained with an isothermal packed bed reactor. While the catalyzed gasification of coal chars is highly complex, depending on a variety of physiochemical phenomena, several conclusions have been drawn. The reactions appear chemically limited at gasification conditions, rather than mass transport limited. Alkali metal salts appear to be the most effective catalysts and, within the alkali series Cs > K > Na > Li, though in steam it appears that hydrated salts of Li and Cs have sufficient volatility to be lost from the reaction vessel. Less effective are the alkaline earth salts which also exhibit an inverse periodic trend in efficacy with Ba > Sr > Ca. Anions appear to have a second order effect. The effect of varyingmore » catalyst concentration is highly dependent on the nature of the catalyst. The catalysts exhibit considerable mobility at temperatures below their melting points and even below gasification temperatures. A significant percentage of active catalyst reacts with indigenous mineral matter within the first several minutes of gasification. Then the reactivity generally remains constant until concentration effects dominate as the substrate is depleted. Enhanced mobility is also evidenced in the case of catalysts based upon eutectic alkali salt mixtures; reactivity is generally higher, at the same conditions, than is observed for a similar concentration of a pure alkali salt.« less
Long Gradient Index Lens Multiphoton Endoscopic Systems (2011)

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text D. M. Huland, S. S. Howard, W. W. Webb, and C. Xu, "Long Gradient Index Lens Multiphoton Endoscopic Systems," in Optics in the Life Sciences, OSA Technical Digest (CD) (Optica Publishing Group, 2011), paper JTuA8. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article
Agile photonic generation of arbitrary RF chirped waveforms (2017)

We demonstrate a simple platform for reconfigurable generation of arbitrary RF chirped waveforms from a single CW laser. Our scheme is capable of generating >100 GHz bandwidth chirps with a time-bandwidth product up to ~1300.
Effect of <i>in situ</i> hydrogen plasma on the ferroelectricity of hafnium zirconium oxide films (2020)

The emerging field of ferroelectric hafnium zirconium oxide has garnered increased attention recently for its wide array of applications from nonvolatile memory and transistor devices to nanoelectromechanical transducers. Atomic layer deposition is one of the preferred techniques for the fabrication of hafnium zirconium oxide thin films, with a standard choice of oxidizer being either O3 or H2O. In this study, we explore various oxidizing conditions and report on the in situ treatment of hydrogen plasma after every atomic layer during the deposition of hafnium zirconium oxide to increase the virgin state polarization. Three different oxidization methods were utilized during the fabrication of the Hf0.5Zr0.5O2 films: H2O, O2 plasma, and O2 plasma followed by H2 plasma. The 10 and 8 nm thick films oxidized with only O2 plasma result in initially anti-ferroelectric films. Comparatively, the addition of H2 plasma after every O2 plasma step results in films with strong ferroelectric behavior. Peak shifting of the GIXRD pattern suggests that the sequential O2-H2 plasma films tend more to the orthorhombic phase as compared to the O2 plasma and H2O oxidized films.
Diamond Synthesis By DC Plasma Jet CVD (1990)

We developed a high-speed diamond synthesis technique called DIA-JET process that uses a DC plasma jet. Diamond is made by spraying the plasma jet (generated from the DC arc discharge) onto a water-cooled substrate. After examining the film with X-ray diffraction, Vickers hardness, and Raman scattering, we found that the quality approximated that of natural diamond. This paper describes the properties of the plasma jet and the synthesized diamond.
Recursive stream selection for CF MU-MIMO BC precoder design (2011)

A to maximize sum rate (SR). Some of the solutions, especially the iterative ones, are capable of achieving very high performance. Nevertheless, they suffer from convergence problems. Closed form (CF) solutions on the other hand offer poor performances. This paper proposes a novel CF precoder design algorithm for the MU-MIMO BC, facilitated by stream selection. The proposed algorithm constructs the precoders per stream in a recursive manner. It contains two complementary steps: The first step consists in a recursive selection of the best available streams to minimize interference between users. This selection procedure is based on a null space criterion combined with the eigenvalues for each available stream. In the second step, the precoders are calculated according to the chosen precoding technique with eventually a power distribution optimization. Several precoding techniques can be applied, namely ZF (Zero Forcing) or MMSE (Minimum Mean Squared Error) linear beamforming (BF) and DPC (Dirty Paper Coding). We compare the proposed algorithm to some of the best CF algorithms available in the literature such as an all user SVD based recursive solution with ZF DPC precoders (ZFDPC-SUS). The obtained results demonstrate better performances for the proposed algorithm, closer to the sum capacity. We also show through a brief theoretical study that the SR of the proposed algorithm converges toward the DPC performance when the number of users grows to infinity.
“Unexpected mutations after CRISPR-Cas9 editing <i>in vivo</i> ” are most likely pre-existing sequence variants and not nuclease-induced mutations (2017)

Schaefer et al . recently advanced the provocative conclusion that CRISPR-Cas9 nuclease can induce off-target alterations at genomic loci that do not resemble the intended on-target site. 1 Using high-coverage whole genome sequencing ( WGS ), these authors reported finding SNPs and indels in two CRISPR-Cas9-treated mice that were not present in a single untreated control mouse. On the basis of this association, Schaefer et al . concluded that these sequence variants were caused by CRISPR-Cas9. This new proposed CRISPR-Cas9 off-target activity runs contrary to previously published work 2–8 and, if the authors are correct, could have profound implications for research and therapeutic applications. Here, we demonstrate that the simplest interpretation of Schaefer et al.’s data is that the two CRISPR-Cas9-treated mice are actually more closely related genetically to each other than to the control mouse. This strongly suggests that the so-called “unexpected mutations” simply represent SNPs and indels shared in common by these mice prior to nuclease treatment. In addition, given the genomic and sequence distribution profiles of these variants, we show that it is challenging to explain how CRISPR-Cas9 might be expected to induce such changes. Finally, we argue that the lack of appropriate controls in Schaefer et al.’s experimental design precludes assignment of causality to CRISPR-Cas9. Given these substantial issues, we urge Schaefer et al . to revise or re-state the original conclusions of their published work so as to avoid leaving misleading and unsupported statements to persist in the literature.
Competitive reverse transcription-polymerase chain reaction analysis indicates that levels of aromatase cytochrome P450 transcripts in adipose tissue of buttocks, thighs, and abdomen of women increase with advancing age. (1994)

Circulating androstenedione is converted to estrone in adipose tissue, which is the principal site of estrogen biosynthesis in postmenopausal women. This reaction is catalyzed by a specific form of cytochrome P450 (P450arom; the product of the CYP19 gene). The fractional conversion of plasma androstenedione to estrone as well as the specific activity of aromatase in adipose stromal cells were previously shown to increase with advancing age. To determine whether this positive effect of aging on estrogen biosynthesis is due to an alteration in tissue levels of P450arom transcripts, we quantified P450arom mRNA levels in sc fat biopsy samples (n = 33) from buttocks, thighs, and abdomen of 11 women who ranged in age from 23-61 yr. Competitive polymerase chain reaction linked to reverse transcription was used to quantify P450arom transcripts in total RNA that was isolated from sc fat obtained by needle aspiration. In each sample, primer extension and coamplification of a rat P450arom cRNA as an internal standard were used to control possible differences in amplification efficiencies between samples. The results demonstrate that with advancing age in women, there is a progressive and statistically significant increase in adipose tissue P450arom transcript levels (normalized to total RNA content) in buttocks, thighs, and abdomen (correlation coefficients: r = 0.704, 0.854, and 0.933, respectively). The levels of transcripts observed in the older subjects reach 2- to 4-fold greater than those observed in the young women. Adipose tissue P450arom transcript levels were highest in the buttocks, followed by the thighs, and lowest in the abdomen. This increase in P450arom transcript levels is likely to be a major factor contributing to the increased extragonadal estrogen biosynthesis in elderly women.
Control of Myocardial Contractile Function by the Level of β-Adrenergic Receptor Kinase 1 in Gene-targeted Mice (1998)

We studied the effect of alterations in the level of myocardial beta-adrenergic receptor kinase betaARK1) in two types of genetically altered mice. The first group is heterozygous for betaARK1 gene ablation, betaARK1(+/-), and the second is not only heterozygous for betaARK1 gene ablation but is also transgenic for cardiac-specific overexpression of a betaARK1 COOH-terminal inhibitor peptide, betaARK1(+/-)betaARKct. In contrast to the embryonic lethal phenotype of the homozygous betaARK1 knockout (Jaber, M., Koch, W. J., Rockman, H. A., Smith, B., Bond, R. A., Sulik, K., Ross, J., Jr., Lefkowitz, R. J., Caron, M. G., and Giros, B. (1996) Proc. Natl. Acad. Sci. U. S. A. 93, 12974-12979), betaARK1(+/-) mice develop normally. Cardiac catheterization was performed in mice and showed a stepwise increase in contractile function in the betaARK1(+/-) and betaARK1(+/-)betaARKct mice with the greatest level observed in the betaARK1(+/-)betaARKct animals. Contractile parameters were measured in adult myocytes isolated from both groups of gene-targeted animals. A significantly greater increase in percent cell shortening and rate of cell shortening following isoproterenol stimulation was observed in the betaARK1(+/-) and betaARK1(+/-)betaARKct myocytes compared with wild-type cells, indicating a progressive increase in intrinsic contractility. These data demonstrate that contractile function can be modulated by the level of betaARK1 activity. This has important implications in disease states such as heart failure (in which betaARK1 activity is increased) and suggests that betaARK1 should be considered as a therapeutic target in this situation. Even partial inhibition of betaARK1 activity enhances beta-adrenergic receptor signaling leading to improved functional catecholamine responsiveness.
Patient Perspectives on Deep Brain Stimulation Clinical Research in Early Stage Parkinson’s Disease (2016)

The FDA has approved a multicenter, double-blind, Phase III, pivotal trial testing deep brain stimulation (DBS) in 280 people with very early stage Parkinson's disease (PD; IDE#G050016). In partnership with The Michael J. Fox Foundation for Parkinson's Research, we conducted a survey to investigate motivating factors, barriers, and gender differences among potentially eligible patients for participation in a trial testing DBS in early PD compared to standard medical treatment. The majority of survey respondents (72%) indicated they would consider learning more about participating. Early PD patients are therefore likely to consider enrolling in trials of invasive therapies that may slow symptom progression and help future patients.
Taccalonolide Binding to Tubulin Imparts Microtubule Stability and Potent <i>In Vivo</i> Activity (2013)

The taccalonolides are highly acetylated steroids that stabilize cellular microtubules and overcome multiple mechanisms of taxane resistance. Recently, two potent taccalonolides, AF and AJ, were identified that bind to tubulin directly and enhance microtubule polymerization. Extensive studies were conducted to characterize these new taccalonolides. AF and AJ caused aberrant mitotic spindles and bundling of interphase microtubules that differed from the effects of either paclitaxel or laulimalide. AJ also distinctly affected microtubule polymerization in that it enhanced the rate and extent of polymerization in the absence of any noticeable effect on microtubule nucleation. In addition, the resulting microtubules were found to be profoundly cold stable. These data, along with studies showing synergistic antiproliferative effects between AJ and either paclitaxel or laulimalide, suggest a distinct binding site. Direct binding studies demonstrated that AJ could not be displaced from microtubules by paclitaxel, laulimalide, or denaturing conditions, suggesting irreversible binding of AJ to microtubules. Mass spectrometry confirmed a covalent interaction of AJ with a peptide of β-tubulin containing the cyclostreptin-binding sites. Importantly, AJ imparts strong inter-protofilament stability in a manner different from other microtubule stabilizers that covalently bind to tubulin, consistent with the distinct effects of the taccalonolides as compared with other stabilizers. AF was found to be a potent and effective antitumor agent that caused tumor regression in the MDA-MB-231 breast cancer xenograft model. The antitumor efficacy of some taccalonolides, which stabilize microtubules in a manner different from other microtubule stabilizers, provides the impetus to explore the therapeutic potential of this site.
Highly sensitive multi-channel atomic magnetometer (2018)

We describe a high-sensitivity 16-channel magnetic sensor based on a spin-exchange relaxation-free (SERF) atomic magnetometer, the most sensitive cryogen-free magnetic field sensor. It has been developed in order to accelerate magnetic measurements in various fields, such as neuroscience and biomedical research, and improve the current technologies. The multi-channel operation is based on a single large flat pancake rubidium vapor cell, two broad laser beams (one for optical pumping and the other for optical Faraday effect detection), and a 4 by 4 photodiode matrix. In addition, a nearly parallel configuration of laser beams and multi-mode fibers facilitate the multi-channel design and the coupling of lasers, respectively. We experimentally demonstrate sensitivity in each channel of the sensor of a few tens femtotesla at low frequency. Because of its high sensitivity and parallel multi-channel detection, we anticipate that this sensor will be useful for many applications, such as magnetoencephalography (MEG), magnetocardiography (MCG), and magnetic micro-particle imaging.
24-Homologated 1,25-dihydroxyvitamin D3 compounds: separation of calcium and cell differentiation activities (1990)

A series of 24-homologated 1,25-dihydroxyvitamin D3 compounds have been chemically synthesized and studied with regard to their activity in inducing differentiation of human promyelocyte HL-60 cells to monocytes and in calcium mobilizing activity in vitamin D deficient rats. Homologation of 1,25-dihydroxyvitamin D3 or its delta 22 analogue by one or two carbons increases by 10-fold and three-carbon homologation reduces by half the activity in causing differentiation of HL-60. On the other hand, homologation causes a substantial decrease in in vivo calcium mobilization activity. The addition of each carbon at the 24-position decreases binding to the HL-60 receptor or rat intestinal receptor by 5-10-fold so that binding affinity of the trihomo compound for the receptors is 130 times less that of 1,25-dihydroxyvitamin D3. Thus, binding affinity for the receptor cannot account for the preferential activity of the 24-homologated compounds in inducing cell differentiation.
A solid-state intraoperative beta probe system (2000)

Successful beta-sensitive intraoperative probes must be capable of detecting relatively small amounts of beta-emitting radionuclides in an environment where a significant photon background exists. The probe system described in this investigation utilized a new photon correction scheme consisting of a stark of two ion-implanted-silicon detectors (IISDs) mounted in a compact unit. The rear detector operated as a photon monitor, whose data was used to correct for photon contamination present in the front detector's readings. The completely battery-powered system incorporated a computer-controlled data acquisition and processing system. Positron and photon detection sensitivities were measured using fluorine-18. The probe was found to have a positron detection sensitivity of 7.21/spl plusmn/0.11 cps/nCi and a 0.0001/spl plusmn/0.0389 cps/nCi photon detection sensitivity. In a simulated search for tumor remnants following a tumor resection using a phantom presenting a realistic annihilation photon background, the intraoperative probe was capable of definitively identifying 12-mm- and 6-mm-diameter, 1-mm-thick disks of simulated tumor.
Rapid Identification of <i>Candida</i> Species and Other Clinically Important Yeast Species by Flow Cytometry (2005)

Two rapid diagnostic assays, utilizing two different Luminex flow cytometry methods, were developed for identification of clinically important ascomycetous yeast species. Direct hybridization and allele-specific primer extension methods were both successful in establishing a DNA-based assay that can rapidly and accurately identify Candida albicans, Candida krusei, Candida parapsilosis, Candida glabrata, and Candida tropicalis as well as other clinical species. The direct hybridization assay was designed to identify a total of 19 ascomycetous yeast species, and the allele-specific primer extension assay was designed to identify a total of 34 species. Probes were validated against 438 strains representing 303 species. From culture to identification, the allele-specific primer extension method takes 8 h and the direct hybridization method takes less than 5 h to complete. These assays represent comprehensive, rapid tests that are well suited for the clinical laboratory.
20.4: Printable Triode Structure Carbon Nanotubes Field Emission Display (2001)

Abstract A 4‐inch, 64×256 pixels, diode structure carbon nanotubes (CNT) field emission displays have been fabricated after screen printing and vacuum sealing process. The design and process for CNT‐emitters arrays of triode structure were studied and developed. The dielectric layer and gate electrode were fabricated by printing on cathode plate.
Advances in in vitro genetic code reprogramming in 2014–2017 (2018)

To date, various genetic code manipulation methods have been developed to introduce non-proteinogenic amino acids into peptides by translation. However, the number of amino acids that can be used simultaneously remains limited even using these methods. Additionally, the scope of amino acid substrates that are compatible with ribosomal translation systems is also limited. For example, difficult substrates such as d-amino acids and β-amino acids are much less efficiently incorporated into peptides than l-α-amino acids. Here, we focus on three recently developed methodologies that address these issues: (i) artificial division of codon boxes to increase the number of available amino acids, (ii) orthogonal ribosomal translation systems to 'duplicate' the codon table and (iii) development of novel artificial tRNAs that enhance incorporation of difficult amino acid substrates.
Ground adaptive standing controller for a powered transfemoral prosthesis (2011)

The scope of this work is the design and verification of a new standing controller for a powered knee and ankle prosthesis. The controller is based upon a finite-state impedance control approach previously developed by the authors. The controller provides a comprehensive standing behavior that incorporates ground adaptation for unlevel terrain. An amputee subject tested the controller with a powered prosthesis for a variety of standing conditions. Results indicate that the powered prosthesis can estimate the ground slope within ±1 degree over a range of ±15 degrees, and that it can provide appropriate joint impedances for standing on slopes within this range.
Development of a Portable Unit for Metabolic Analysis (2004)

The purpose of this research is to develop, test and calibrate a prototype portable device that will measure human metabolic activity; namely time resolved measurements of gas temperature, pressure and flow-rate, and oxygen and carbon dioxide partial pressure during inhalation and exhalation.
De novo designed protein inhibitors of amyloid aggregation and seeding (2022)

Neurodegenerative diseases are characterized by the pathologic accumulation of aggregated proteins. Known as amyloid, these fibrillar aggregates include proteins such as tau and amyloid-β (Aβ) in Alzheimer's disease (AD) and alpha-synuclein (αSyn) in Parkinson's disease (PD). The development and spread of amyloid fibrils within the brain correlates with disease onset and progression, and inhibiting amyloid formation is a possible route toward therapeutic development. Recent advances have enabled the determination of amyloid fibril structures to atomic-level resolution, improving the possibility of structure-based inhibitor design. In this work, we use these amyloid structures to design inhibitors that bind to the ends of fibrils, "capping" them so as to prevent further growth. Using de novo protein design, we develop a library of miniprotein inhibitors of 35 to 48 residues that target the amyloid structures of tau, Aβ, and αSyn. Biophysical characterization of top in silico designed inhibitors shows they form stable folds, have no sequence similarity to naturally occurring proteins, and specifically prevent the aggregation of their targeted amyloid-prone proteins in vitro. The inhibitors also prevent the seeded aggregation and toxicity of fibrils in cells. In vivo evaluation reveals their ability to reduce aggregation and rescue motor deficits in <i>Caenorhabditis elegans</i> models of PD and AD.