gebhart/patrepeval huggingface dataset:
CuZn Superoxide Dismutase (SOD-1):Tetanus Toxin Fragment C Hybrid Protein for Targeted Delivery of SOD-1 to Neuronal Cells (1995)

Increased levels of CuZn superoxide dismutase (SOD-1) are cytoprotective in experimental models of neurological disorders associated with free radical toxicity (e.g. stroke, trauma). Targeted delivery of SOD-1 to central nervous system neurons may therefore be therapeutic in such diseases. The nontoxic C-fragment of tetanus toxin (TTC) possesses the nerve cell binding/transport properties of tetanus holotoxin and has been used as a vector to enhance the neuronal uptake of proteins including enzymes. We have now produced a recombinant, hybrid protein in Escherichia coli tandemly joining human SOD-1 to TTC. The expressed hybrid protein (SOD:Tet450) has a subunit molecular mass of 68 kDa and is recognized by both anti-SOD-1 and anti-TTC antibodies. Calculated per mol, SOD:Tet450 has approximately 60% of the expected SOD-1 enzymatic activity. Analysis of the hybrid protein's interaction with the neuron-like cell line, N18-RE-105, and cultured hippocampal neurons by enzyme immunoassay for human SOD-1 revealed that SOD:Tet451 association with cells was neuron-specific and dose-dependent. The hybrid protein was also internalized, but there was substantial loss of internalized hybrid protein over the first 24 h. Hybrid protein associated with cells remained enzymatically active. These results suggest that human SOD-1 and TTC retain their respective functional properties when expressed together as a single peptide. SOD:Tet451 may prove to be a useful agent for the targeted delivery of SOD-1 to neurons.
A Resonator for Low-Threshold Frequency Conversion (2004)

A proposed toroidal or disklike dielectric optical resonator (dielectric optical cavity) would be made of an optically nonlinear material and would be optimized for use in parametric frequency conversion by imposition of a spatially periodic permanent electric polarization. The poling (see figure) would suppress dispersions caused by both the material and the geometry of the optical cavity, thereby effecting quasi-matching of the phases of high-resonance-quality (high-Q) whispering-gallery electromagnetic modes. The quasi-phase-matching of the modes would serve to maximize the interactions among them. Such a resonator might be a prototype of a family of compact, efficient nonlinear devices for operation over a broad range of optical wavelengths. A little background information is prerequisite to a meaningful description of this proposal: (1) Described in several prior NASA Tech Briefs articles, the whispering-gallery modes in a component of spheroidal, disklike, or toroidal shape are waveguide modes that propagate circumferentially and are concentrated in a narrow toroidal region centered on the equatorial plane and located near the outermost edge. (2) For the sake of completeness, it must be stated that even though optical resonators of the type considered here are solid dielectric objects and light is confined within them by total internal reflection at dielectric interfaces without need for mirrors, such components are sometimes traditionally called cavities because their effects upon the light propagating within them are similar to those of true cavities bounded by mirrors. (3) For a given set of electromagnetic modes interacting with each other in an optically nonlinear material (e.g., modes associated with the frequencies involved in a frequency-conversion scheme), the threshold power for oscillation depends on the mode volumes and the mode-overlap integral. (4) Whispering-gallery modes are attractive in nonlinear optics because they maximize the effects of nonlinearities by occupying small volumes and affording high Q values
Synthesis, Development, and Testing of High-Surface-Area Polymer-Based Adsorbents for the Selective Recovery of Uranium from Seawater (2016)

The ocean contains uranium with an approximate concentration of 3.34 ppb, which can serve as an incredible supply source to sustain nuclear energy in the United States. Unfortunately, technology currently available to recover uranium from seawater is not efficient enough and mining uranium on land is still more economical. We have developed polymer-based adsorbents with high uranium adsorption capacities by grafting amidoxime onto high-surface-area polyethylene (PE) fibers. Various process conditions have been screened, in combination with developing a rapid testing protocol (<24 h), to optimize the process. These adsorbents are synthesized through radiation-induced grafting of acrylonitrile (AN) and methacrylic acid (MAA) onto PE fibers, followed by the conversion of nitriles to amidoximes and basic conditioning. In addition, the uranium adsorption capacity, measured in units of gU/kgads, is greatly increased by reducing the diameter of the PE fiber or changing its morphology. An increase in the surface area of the PE polymer fiber allows for more grafting sites that are positioned in more-accessible locations, thereby increasing access to grafted molecules that would normally be located in the interior of a fiber with a larger diameter. Polymer fibers with hollow morphologies are able to adsorb beyond 1 order of magnitude more uranium from simulated seawater than current commercially available adsorbents. Several high-surface-area fibers were tested in natural seawater and were able to extract 5–7 times more uranium than any adsorbent reported to date.
Adaptive model predictive control using neural networks (1994)

The authors work in controlling chemical processes included the following: (1) to develop neural networks and training procedures that are well suited to: small amounts of off-line training data for on-line control of systems with substantial time lags; (2) to develop generic Model Predictive Control (MPC) software; and (3) to control the following simulated systems using MPC: continuously stirred tank reactor with jacket dynamics; plasma etching model for semiconductor manufacture; and distillation columns. Details descriptions are given of the three points.
Optimum Three-Dimensional Constellations for Stokes Vector Direct Detect Receivers (2019)

We propose optimum 3D signal constellations for short reach intra-datacenter interconnects using stokes vector receivers. These optimum 3D alphabets maximize the so-called constellation figure of merit, which is the ratio between the squared minimum Euclidean distance and the average energy of the constellation points. Compared to dual-polarization 4-ary and 8-ary pulse amplitude modulation formats, the optimized 16-point and 64-point 3D signal constellations theoretically achieve 4 and 6 dB improved receiver sensitivity at low symbol error rates of ~10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> , while delivering similar spectral efficiencies of 4 and 6 bits per 3D symbol, respectively. Next, we experimentally verified the significant improvement in receiver sensitivity at symbol rates of 44 and 64 Gbaud that result from using the proposed optimized 3D signal alphabets.
Coding unit splitting early termination for fast HEVC intra coding based on global and directional gradients (2016)

High efficiency video coding (HEVC) doubles the compression ratio as compared to H.264/AVC, for the same quality. To achieve this improved coding performance, HEVC presents a new content-adaptive approach to split a frame into coding units (CUs), along with an increased number of prediction modes, which results in significant computational complexity. To lower this complexity with intra coding, in this paper, we develop a new method based on global and directional gradients to terminate the CU splitting procedure early and prevent processing of unnecessary depths. The global and directional gradients determine if the unit is predicted with high accuracy at the current level, and where that's the case, the CU is deemed to be non-split. Experimental results show that the proposed method reduces the encoding time by 52% on average, with a small quality loss of 0.07 dB (BD-PSNR) for all-intra scenarios, as compared to the HEVC reference implementation, HM 15.0.
Electrically Actuated Hydraulic Solids (2016)

The authors introduce a new class of electrically‐actuated soft materials. Electro‐active hydraulic solids (EAHSs) are comprised of numerous microscale phase change capsules embedded inside a conductive elastomer matrix which replicate traditional wax actuators in a massively parallel fashion. EAHS can generate forces and stress densities that exceed traditional electroactive actuators. For example, a 14 mm diameter 50 mm long cylinder can generate 4 500 N force and have over 3% strain. The authors describe a simple method for fabricating EAHS and demonstrate their compatibility with a wide range of manufacturing processes including additive manufacturing, subtractive manufacturing, and forming.
Integrating Activity with Accessibility in Olefin Metathesis: An Unprecedentedly Reactive Ruthenium-Indenylidene Catalyst (2019)

Access to leading olefin metathesis catalysts, including the Grubbs, Hoveyda, and Grela catalysts, ultimately rests on the nonscaleable transfer of a benzylidene ligand from an unstable, impure aryldiazomethane. The indenylidene ligand can be reliably installed, but to date yields much less reactive catalysts. A fast-initiating, dimeric indenylidene complex (<b>Ru-1</b>) is reported, which reconciles high activity with scaleable synthesis. Each Ru center in <b>Ru-1</b> is stabilized by a state-of-the-art cyclic alkyl amino carbene (CAAC, <b>C1</b>) and a bridging chloride donor: the lability of the latter elevates the reactivity of <b>Ru-1</b> to a level previously attainable only with benzylidene derivatives. Evaluation of initiation rate constants reveals that <b>Ru-1</b> initiates >250× faster than indenylidene catalyst <b>M2</b> (RuCl<sub>2</sub>(H<sub>2</sub>IMes)(PCy<sub>3</sub>)(Ind)), and 65× faster than <b>UC</b> (RuCl<sub>2</sub>(<b>C1</b>)<sub>2</sub>(Ind)). The slow initiation previously regarded as characteristic of indenylidene catalysts is hence due to low ligand lability, not inherently slow cycloaddition at the Ru=CRR' site. In macrocyclization and "ethenolysis" of methyl oleate (i.e., transformation into α-olefins via cross-metathesis with C<sub>2</sub>H<sub>4</sub>), <b>Ru-1</b> is comparable or superior to the corresponding, breakthrough CAAC-benzylidene catalyst. In ethenolysis, <b>Ru-1</b> is 5× more robust to standard-grade (99.9%) C<sub>2</sub>H<sub>4</sub> than the top-performing catalyst, probably reflecting steric protection at the quaternary CAAC carbon.
Comparison of Set-Partitioned Two-Polarization 16QAM Formats with PDM-QPSK and PDM-8QAM for Optical Transmission Systems with Error-Correction Coding (2012)

We compare set partitioned two-polarization 16QAM formats with conventional PDM-QPSK and PDM-8QAM formats by considering error correction coding. We particularly show that 128SP-16QAM appear as a competitive alternative to PDM-8QAM for spectrally efficient (>4 b/s/Hz) optical transmission systems using forward error-correction coding.
RIDE QUALITY CRITERIA OF MULTIFACTOR ENVIRONMENTS (1978)

A comprehensive ride quality model that accounts for the effects of multifrequency and multiaxis vibration inputs as well as the interactive effects of noise and vibration upon passenger discomfort is under development. The model development has been based upon extensive experimental studies utilizing a realistic multi-degree-of-freedom laboratory simulator located at the Langley Research Center, Hampton, Virginia. This paper briefly describes the basic elements of the ride quality model; presents summary data relating to human discomfort response to vertical, lateral, and roll vibrations; and concludes with a description of the results of an initial study of human response to combined noise and vibration stimuli. Results of studies involving vibration stimuli alone are presented in terms of sets of equal discomfort curves for each of the previously mentioned axes of vibration. In addition, a set of noise-vibration criteria curves are included based upon the concept of additivity of the discomfort components due to noise and to vibration. This assumption is shown to be valid for the restricted range of stimuli used in this study. /Author/
Analysis of A Novel Slurry Injection System in Chemical Mechanical Planarization (2011)

Slurry mean residence time (MRT), removal rate, and polishing defects were analyzed for a novel slurry injection system used in chemical mechanical planarization. The novel slurry injection system was placed adjacent to the wafer on the pad surface and slurry was injected towards the wafer through multiple holes in the trailing edge of the injector bottom. Results showed the novel slurry injection system provided more efficient slurry delivery to the pad–wafer interface and generated lower slurry MRT, higher removal rate, and lower polishing defects than the standard pad center area slurry application method currently used in the IC manufacturing industry.
Panorama weaving (2012)

A fundamental step in stitching several pictures to form a larger mosaic is the computation of boundary seams that minimize the visual artifacts in the transition between images. Current seam computation algorithms use optimization methods that may be slow, sequential, memory intensive, and prone to finding suboptimal solutions related to local minima of the chosen energy function. Moreover, even when these techniques perform well, their solution may not be perceptually ideal (or even good). Such an inflexible approach does not allow the possibility of user-based improvement. This paper introduces the Panorama Weaving technique for seam creation and editing in an image mosaic. First, Panorama Weaving provides a procedure to create boundaries for panoramas that is fast, has low memory requirements and is easy to parallelize. This technique often produces seams with lower energy than the competing global technique. Second, it provides the first interactive technique for the exploration of the seam solution space. This powerful editing capability allows the user to automatically extract energy minimizing seams given a sparse set of constraints. With a variety of empirical results, we show how Panorama Weaving allows the computation and editing of a wide range of digital panoramas including unstructured configurations.
High-G Hardened Sensors (2010)

The state of the art in shock resistant accelerometer and gyro design is to use smaller proof mass, thereby reducing the related forces that are generated as a result of high acceleration levels. Physical stops are also provided to limit the maximum proof mass displacement/rotation. The introduction of MEMS technology has made it possible to significantly reduce the proof mass. However, all existing accelerometer/gyro designs for high shock resistance suffer from low sensitivity at the very low acceleration levels required for guidance and control purposes, and from long settling time. The basic method of design and the concepts described in this patent provide the means to alleviate these shortcomings. The novelty in these designs is in the provision of the means to lock the proof mass in its “null” position during the high accelerations, such as during shock (impact) loading, and release it afterwards. The locking mechanism may be passive or active. As a result, the settling time of the proof mass is minimized and the precision with which the sensor can make its measurements is significantly increased.
Thermoacoustic computed tomography of the breast at 434 MHz (2003)

The authors have constructed a thermoacoustic tomography (TACT) imaging device for mapping the three-dimensional absorption of 434 MHz radiowaves in the human breast. Contrast variations in these images reflect differences in bound water content of the constituent tissues of the breast. As anticipated, initial images have displayed excellent soft tissue differentiation between fatty and fibroglandular tissue with spatial resolution of 1.5-4 mm throughout a 2000 mm/sup 3/ imaging volume using safe levels of 434 MHz radiation. The imaging technique has great potential for breast cancer detection.
Processing of a Novel Multilayered Silicon Nitride (1996)

A new type of silicon nitride with a layered structure of alternating dense and porous layers was obtained by addition of β‐Si 3 N 4 whiskers to the porous layers. The materials consisted of dense layers 60 μm thick and porous layers 40 μm thick with a final porosity of about 30%. Highly anisotropic shrinkage behavior was observed during sintering. A large addition of whiskers to the porous layers resulted in layers with well‐oriented and tightly tangled elongated grains, where porosity is represented by anisotropic shaped pores.
Enhanced Optical <sup>13</sup> C Hyperpolarization in Diamond Treated by High‐Temperature Rapid Thermal Annealing (2020)

Abstract Methods of optical dynamic nuclear polarization open the door to the replenishable hyperpolarization of nuclear spins, boosting their nuclear magnetic resonance/imaging signatures by orders of magnitude. Nanodiamond powder rich in negatively charged nitrogen vacancy defect centers has recently emerged as one such promising platform, wherein 13 C nuclei can be hyperpolarized through the optically pumped defects completely at room temperature. Given the compelling possibility of relaying this 13 C polarization to nuclei in external liquids, there is an urgent need for the engineered production of highly “hyperpolarizable” diamond particles. Here, a systematic study of various material dimensions affecting optical 13 C hyperpolarization in diamond particles is reported on. It is discovered surprisingly that diamond annealing at elevated temperatures ∼1720 °C has remarkable effects on the hyperpolarization levels enhancing them by above an order of magnitude over materials annealed through conventional means. It is demonstrated these gains arise from a simultaneous improvement in NV − electron relaxation/coherence times, as well as the reduction of paramagnetic content, and an increase in 13 C relaxation lifetimes. This work suggests methods for the guided materials production of fluorescent, 13 C hyperpolarized, nanodiamonds and pathways for their use as multimodal (optical and magnetic resonance) imaging and hyperpolarization agents.
Laser-driven hydrothermal process studied with excimer laser pulses (2017)

Previously, we discovered [Mariella et al., J. Appl. Phys. 114, 014904 (2013)] that modest-fluence/modest-intensity 351-nm laser pulses, with insufficient fluence/intensity to ablate rock, mineral, or concrete samples via surface vaporization, still removed the surface material from water-submerged target samples with confinement of the removed material, and then dispersed at least some of the removed material into the water as a long-lived suspension of nanoparticles. We called this new process, which appears to include the generation of larger colorless particles, “laser-driven hydrothermal processing” (LDHP) [Mariella et al., J. Appl. Phys. 114, 014904 (2013)]. We, now, report that we have studied this process using 248-nm and 193-nm laser light on submerged concrete, quartzite, and obsidian, and, even though light at these wavelengths is more strongly absorbed than at 351 nm, we found that the overall efficiency of LDHP, in terms of the mass of the target removed per Joule of laser-pulse energy, is lower with 248-nm and 193-nm laser pulses than with 351-nm laser pulses. Given that stronger absorption creates higher peak surface temperatures for comparable laser fluence and intensity, it was surprising to observe reduced efficiencies for material removal. We also measured the nascent particle-size distributions that LDHP creates in the submerging water and found that they do not display the long tail towards larger particle sizes that we had observed when there had been a multi-week delay between experiments and the date of measuring the size distributions. This is consistent with transient dissolution of the solid surface, followed by diffusion-limited kinetics of nucleation and growth of particles from the resulting thin layer of supersaturated solution at the sample surface.
A Tactile Sensing System for Robotic Manipulation (1990)

A tactile sensing system (TSS) for articulated robotic hands is described. The system is composed of flexible touch sensing arrays, access electronics, and algorithms for data sampling and processing. The TSS is meant to exist in a multiprocess ing control environment and is designed to keep low-level procedures such as sensor addressing and data access off of the control system's shared bus. Up to 16 arrays of 256 taxels each can be accessed in parallel with achieved sampling rates of more than 60 Hz. The resolution of the sensors can be dynamically modified by a simple switching technique. This allows very fast sampling rates at low resolution while retain ing the ability to sample with high precision at lower rates. Variance of the resolution changes only the number of taxels and the size of their receptive fields but does not affect the coverage of the array. As part of the discussion about TSS, a generic class of resistive touch sensors is described. These sensors are inex pensive, flexible, and easy to build. Methods for efficient sampling, variable resolution, and shear force detection are introduced, and implementation issues for use with the Utah/ MIT Dextrous Hand are discussed.
Development of Genetic Dereplication Strains in <i>Aspergillus nidulans</i> Results in the Discovery of Aspercryptin (2015)

To reduce the secondary metabolite background in Aspergillus nidulans and minimize the rediscovery of compounds and pathway intermediates, we created a "genetic dereplication" strain in which we deleted eight of the most highly expressed secondary metabolite gene clusters (more than 244,000 base pairs deleted in total). This strain allowed us to discover a novel compound that we designate aspercryptin and to propose a biosynthetic pathway for the compound. Interestingly, aspercryptin is formed from compounds produced by two separate gene clusters, one of which makes the well-known product cichorine. This raises the exciting possibility that fungi use differential regulation of expression of secondary metabolite gene clusters to increase the diversity of metabolites they produce.
The Properties of Electrochromic Film Electrodes of Lanthanide Diphthalocyanines in Ethylene Glycol (1985)

The electrochromic properties of film electrodes of lutetium, erbium, gadolinium, and ytterbium diphthalocyanines in contact with ethylene glycol solutions have been studied. The stability of the electrochromic film under electrochemical cycling in this medium is at least three orders of magnitude better than that in neutral aqueous solutions. The stability of the electrochromic is improved if the film is written galvanostatically from the yellow‐tan to the green state. A simplified model for the galvanostatic transition is proposed, and some of the problems of this family of electrochromic materials are discussed.
Genomic Profiling of Hormone-Naïve Lymph Node Metastases in Patients with Prostate Cancer (2006)

The progression of organ-confined prostate cancer to metastatic cancer is inevitably fatal. Consequently, identification of structural changes in the genome and associated transcriptional responses that drive this progression is critical to understanding the disease process and the development of biomarkers and therapeutic targets. In this study, whole genome copy number changes in genomes of hormone-naïve lymph node metastases were profiled using array comparative genomic hybridization, and matched primaries were included for a subset. Matched primaries and lymph node metastases showed very similar copy number profiles that are distinct from primary tumors that fail to metastasize.